Global International
Waters Assessment
Regional assessments
Other reports in this series:
Russian Arctic GIWA Regional assessment 1a
Caribbean Sea/Small Islands GIWA Regional assessment 3a
Caribbean Islands GIWA Regional assessment 4
Barents Sea GIWA Regional assessment 11
Baltic Sea GIWA Regional assessment 17
Caspian Sea GIWA Regional assessment 23
Aral Sea GIWA Regional assessment 24
Gulf of California/Colorado River Basin GIWA Regional assessment 27
Sea of Okhotsk GIWA Regional assessment 30
Oyashio Current GIWA Regional assessment 31
Yellow Sea GIWA Regional assessment 34
East China Sea GIWA Regional assessment 36
Patagonian Shelf GIWA Regional assessment 38
Brazil Current GIWA Regional assessment 39
Amazon Basin GIWA Regional assessment 40b
Canary Current GIWA Regional assessment 41
Guinea Current GIWA Regional assessment 42
Lake Chad Basin GIWA Regional assessment 43
Benguela Current GIWA Regional assessment 44
Indian Ocean Islands GIWA Regional assessment 45b
East African Rift Valley Lakes GIWA Regional assessment 47
South China Sea GIWA Regional assessment 54
Mekong River GIWA Regional assessment 55
Sulu-Celebes (Sulawesi) Sea GIWA Regional assessment 56
Indonesian Seas GIWA Regional assessment 57
Pacifi c Islands GIWA Regional assessment 62
Humboldt Current GIWA Regional assessment 64
Global International
Waters Assessment
Regional assessment 65
Eastern Equatorial Pacific
GIWA report production
Series editor: Ulla Li Zweifel
Editorial assistance: Kristin Bertilius,
Matthew Fortnam, Russell Arthurton
Maps & GIS: Rasmus Göransson
Design & graphics: Joakim Palmqvist
Global International Waters Assessment
Eastern Equatorial Pacifi c, GIWA Regional assessment 65
Published by the University of Kalmar on behalf of
United Nations Environment Programme
© 2006 United Nations Environment Programme
ISSN 1651-940X
University of Kalmar
SE-391 82 Kalmar
Sweden
United Nations Environment Programme
PO Box 30552,
Nairobi, Kenya
This publication may be reproduced in whole or in part and
in any form for educational or non-profi t purposes without
special permission from the copyright holder, provided
acknowledgement of the source is made. No use of this
publication may be made for resale or for any other commercial
purpose whatsoever without prior permission in writing from the
United Nations Environment Programme.
CITATIONS
When citing this report, please use:
UNEP, 2006. Permanent Commission for the South Pacifi c (CPPS).
Eastern Equatorial Pacifi c, GIWA Regional assessment 65.
University of Kalmar, Kalmar, Sweden.
DISCLAIMER
The views expressed in this publication are those of the authors
and do not necessarily refl ect those of UNEP. The designations
employed and the presentations do not imply the expressions
of any opinion whatsoever on the part of UNEP or cooperating
agencies concerning the legal status of any country, territory,
city or areas or its authority, or concerning the delimitation of its
frontiers or boundaries.
This publication has been peer-reviewed and the information
herein is believed to be reliable, but the publisher does not
warrant its completeness or accuracy.
Publishing house: Kirjastusaktsiaselts MATS, Tallinn
Printed in Estonia by Tallinna Raamatutrükikoda, 2006
Contents
Executive summary
9
Abbreviations and acronyms
13
Regional defi nition
16
Boundaries of the Eastern Equatorial Pacifi c region
16
Physical characteristics
17
Socio-economic characteristics
21
Regional cooperation
24
Assessment 26
Freshwater shortage
26
Pollution
32
Habitat and community modifi cation
40
Unsustainable exploitation of fi sh and other living resources
42
Global change
45
Priority concerns for further analysis
47
Causal chain analysis
49
Freshwater shortage
49
Pollution
52
Unsustainable exploitation of fi sh and other living resources
55
Policy options
57
Southwest Mexico
57
Central Equatorial Pacifi c sub-system
59
Pacifi c Colombian sub-system
62
Conclusions and recommendations
64
Southwest Mexico
64
Central Equatorial Pacifi c sub-system
64
Pacifi c Colombian sub-system
65
References 67
Annexes 74
Annex I List of contributing authors and organisations
74
Annex II Detailed scoring tables
75
Annex III Regional agreements, conventions and projects
78
Annex IV Fee-and-rebate system (Southwest Mexico sub-system)
81
The Global International Waters Assessment
i
The GIWA methodology
vii
CONTENTS
Executive summary
Regional Defi nition
the south and the Equatorial Counter-current from the west. The
The GIWA Eastern Equatorial Pacifi c region extends along the west
interactions of these currents result in zones of upwelling with
coast of Central America from the Colombian-Ecuador border in the
productive fi sheries. There are extensive lakes in the region, notably in
south to northern Central Mexico. It includes El Salvador and the Pacifi c
Nicaragua. Two Guatemalean rivers discharge through neighbouring
coastal areas of seven other countries Mexico, Guatemala, Honduras,
countries the Suchiate in Mexico and the Paz in El Salvador. In El
Nicaragua, Costa Rica, Panama and Colombia. The region was divided
Salvador, transboundary rivers include the Paz, shared with Guatemala,
into three sub-systems Southwest Mexico, Central Equatorial Pacifi c
and the Gosgocaran, shared with Honduras. Honduras also shares
and Pacifi c Colombian. The GIWA assessment focuses predominantly
Nicaragua's Negro River.
on the Central Equatorial Pacifi c sub-system as it includes most of the
signifi cant and reported transboundary issues.
Agriculture is the main economic activity in the region, providing
employment for around half of the economically active population.
The Southwest Mexico sub-system extends along 1 800 km of Mexico's
Coastal and artisanal fi sheries have a high socio-economic signifi cance,
Pacifi c coast from the border between the states of Nayarit and Sinaloa
employing around 500 000 fi shermen and processing plant operators.
in the north to the border with Guatemala in the south. The Central
Aquaculture, particularly of shrimps, is growing in the region, with 70% of
Equatorial Pacifi c sub-system includes the western part of the Central
Central America's total production coming from Honduras and Panama.
American isthmus and extends along 3 870 km of Pacifi c coast from
Tourism is also growing, accounting for some 30% of GDP, making it the
the Guatemala-Mexico border in the north to the Panama-Colombia
region's second most important economic activity. Except in Colombia
border in the south. The Pacifi c Colombian sub-system's coast extends
and Mexico, industry is underdeveloped, contributing only 15% to
for 1 300 km from Colombia's border with Panama in the north to its
the regional GDP. There is intensive shipping throughout the region
border with Ecuador.
including an intercontinental maritime route and, notably, the Panama
Canal. Mining of the region's rich mineral resources produces signifi cant
The climate of the Southwest Mexico sub-system ranges from tropical
proportions of the world's totals, especially silver, lead and zinc.
(in the lower-lying coastal areas) to warm temperate. The climate of
the Central Equatorial Pacifi c sub-system is tropical to temperate with
Assessment of the Southwest Mexico sub-system
a winter dry period, when drought conditions occur in a corridor
Pollution was considered to be the priority concern of this sub-
extending from Guatemala to the northern part of Costa Rica; also
system. The enormous amount of untreated wastewater entering
aff ecting parts of Panama. Drought conditions are intensifi ed during
the aquatic environment is deteriorating the environmental quality of
El Niño events. The Pacifi c Colombian sub-system is wet tropical,
the sub-system's water bodies. In Mexico, two thirds of wastewater is
infl uenced by the Intertropical Convergence Zone, its proximity to the
discharged into the Pacifi c Ocean. Microbiological pollution on Mexican
ocean, and the El Niño climatic events.
beaches has been identifi ed as a priority by Mexican authorities due
to the potential eff ects on human health and tourism. Fertiliser use in
The region's marine area is infl uenced by three major current systems
Mexico has increased considerably, causing eutrophication in many
the California Current from the north, the Humboldt Current from
water bodies, notably Lake Chapala where there is a proliferation of
EXECUTIVE SUMMARY
9
algae and invasive aquatic weeds. Closed seasons during HAB events
services has not matched population growth and urban development.
have resulted in economic losses of 200 million USD to the fi sheries
As a consequence, water-related diseases are increasingly prevalent.
industry. Mexico uses more pesticides than any other country in the
Acute diarrheic disease is the main cause of morbidity and infant
GIWA Eastern Equatorial Pacifi c region. However, DDT application has
mortality. Pesticides and fertilisers are used intensively in agriculture.
decreased considerably since the 1960s. Heavy metal contamination
They are responsible, together with domestic wastewater, for causing
is particularly high in the Lerma River basin and Lake Chapala, causing
eutrophication in coastal areas, which is impacting the food security
toxicological induced mutations in some fi sh species. The water bodies
of the coastal population. Pollution of groundwater, a major source of
of the sub-system carry large amounts of suspended solids which are
water for coastal communities, is increasing; higher demand has led to
causing severe sedimentation in lakes and coastal wetlands.
increased abstraction, leading to saline intrusion. Groundwater is also
being polluted by urban and agricultural run-off .
Freshwater shortage was considered to be the second priority concern
of the Southwest Mexico sub-system. Although the rivers are highly
Assessment of the Pacifi c Colombian sub-system
dynamic and characterised by signifi cant inter-annual fl uctuations,
The unsustainable exploitation of fi sh and other living resources was
discharges have shown a decreasing trend over the past 40 years, largely
the principal concern of the sub-system. Despite most of the fi sheries
due to increased abstraction. The availability of water suitable for human
in Colombia being small scale and/or subsistence, the current level of
consumption has declined due to contamination by the discharge of
exploitation is unsustainable; catches of some traditionally targeted
untreated wastewater. The aquifers in the Lerma-Santiago-Pacifi co
species such as mackerel and sharks have declined. Similarly, stocks
basin have been overabstracted mainly to supply water for agriculture.
of freshwater commercial species are signifi cantly depleted. Although
The depletion of groundwater supplies is concerning given that 70% of
there have been no studies of the level of by-catch in the Pacifi c
the basin's population obtain their water supply from aquifers.
Colombian, based on studies in territories within close proximity of the
sub-system, it is believed that large quantities of fi sh are caught as by-
Assessment of the Central Equatorial Pacifi c sub-system
catch in the shrimp trawling industry and the majority are discarded.
Freshwater shortage was considered to be the priority aquatic concern.
Although water resources are abundant they are unevenly distributed,
Pollution was considered by the regional team to be the second
some areas suff ering shortages during the dry season. Pollution,
priority concern. The Pacifi c Colombian sub-system has the highest
deforestation and inappropriate soil management are adversely
rate of fertiliser consumption on the Pacifi c coast of South America
aff ecting downstream transboundary aquatic ecosystems by changing
resulting in some areas, such as Tumaco and Buenaventura, having
the dynamics of accretion and erosion, the supply of nutrients and the
eutrophic conditions. Variable concentrations of pesticides have been
patterns of fl ooding, as well as by reducing the availability and quality
found in water, sediment and organisms at diff erent sites in Colombia.
of water resources. Areas defi cient in water are generally the more
Concentrations of DDTs in surface sediments exceed international
densely populated with the greatest concentration of economic
and national standards. Extensive deforestation has exacerbated
activity. Continuing population growth and economic development
erosion, increasing the amount of sediments entering the rivers.
will increase the demand for water, increasing the extent and severity
Unplanned urban development has resulted in wastes being disposed
of water shortages. Excessive groundwater abstraction is threatening
of inappropriately. Localised oil spills from exploitation, refi ning and
aquifers and resulting in acute water shortages for populations
transport activities have been reported.
dependent on groundwater. Global climate change will aff ect the
future availability of freshwater in the sub-system. Rainfall is expected
Causal chain analysis
to become more intense during the rainy season and droughts more
In the Southwest Mexico sub-system, only a quarter of the population is
severe during the dry season
connected to wastewater treatment facilities. The sewage infrastructure
that does exist is commonly non-operational, with most wastewater
Pollution was identifi ed as the second priority concern. In 2000,
discharged directly into the ocean or inland waterways without
approximately 22% of the population had no access to safe freshwater;
treatment. Coastal tourism development is increasing further the
in rural areas half the population obtained water from polluted natural
pressure on sewer infrastructure. Regulatory agencies have achieved
water bodies. Wastewater discharged without treatment is the most
increasing success in controlling large-volume industrial polluters
widespread pollution issue. Excepting Costa Rica, there is a low level of
whose wastes fl ow into federal waterways. Pollution levels are still high,
sanitation coverage. In general, coverage of sanitation and drinking water
however, due to a lack of direct control over municipal pollution sources
10
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
and weak enforcement power to collect fi nes from municipalities who
(PARCA). The policy options discussed address a range of root causes
exceed federal pollution limits. Local municipal governments lack
identifi ed during the Causal chain analysis:
technical expertise and fi nancial capacity to create and maintain
wastewater treatment networks.
Policy options for addressing microbiological pollution in the Southwest
Mexico sub-system:
In the Central Equatorial Pacifi c sub-system, freshwater shortage
Rehabilitate existing, and construct new, wastewater treatment
is being caused by the modifi cation of stream fl ow, pollution and
facilities;
excessive abstraction of groundwater from aquifers. The demographic
Introduce a fee-and-rebate system for municipal wastewater;
trends of the last four decades have led to increasing demand for
Reduce excess water use;
freshwater resources for drinking water, agricultural production and
Formulate and implement education and information strategies;
industrial processes. Urbanisation has intensifi ed and concentrated
Publicly rate municipalities for their level of compliance with
demand in areas that have limited freshwater availability. The current
wastewater treatment standards;
water distribution systems are obsolete and highly ineffi
cient, but
Create autonomous water districts; and
countries lack the economic resources needed to adopt water-
Reform the pollution-related legal framework.
effi
cient technologies. The development of freshwater supply and
sanitation coverage is not keeping pace with population growth,
Policy options for addressing freshwater shortage in the Central
posing a growing risk for human health. Low tariff rates for water and
Equatorial Pacifi c sub-system
underinvestment in sanitation infrastructure are the principal causes
Integrate territorial planning with water management;
of the lack of basic sanitation services. Most countries have weak legal
Promote new development centres in rural areas;
and institutional frameworks for water management and there is a lack
Strengthen and establish further monitoring programmes;
of a transboundary approach to shared basins. Other shortcomings
Develop and implement environmental awareness programmes;
are a lack of a multidisciplinary approach resulting in inter-institutional
Reorganise the water sector; and
confl icts and a lack of monitoring, control and surveillance for the
Finance the maintenance and expansion of water services by
implementation of existing regulations. There is a dearth of knowledge
introducing water rates.
regarding water quality and the eff ects of pollutants on ecosystems and
their biota. There is also a lack of public awareness of water issues and
Policy options for addressing microbiological pollution in the Central
there is no culture of water conservation. Other than the consumptive
Equatorial Pacifi c sub-system:
benefi ts of water, there is little recognition or valuation of the indirect
Invest in treatment infrastructure;
benefi ts that water provides through ecosystem goods and services.
Adopt the polluter pays-principle;
Review and reform regional and national legal frameworks;
On the Pacifi c Colombian coast, non-selective and destructive fi shing
Strengthen the capacity of the agencies responsible for water
gear is used to increase short-term profi ts at the detriment of fi sh stocks
management;
and marine ecosystems. As the distribution of fi sh species has changed
Develop and implement environmental awareness programmes;
and stocks of traditionally exploited species have declined, the fi shing
and
industry has began to exploit stocks which are further off shore using
Strengthen information management.
new technologies. The fi sheries sector concentrates on certain valuable
species to supply the export, rather than domestic, fi sh market. Existing
Policy options for addressing overexploitation of the fi sheries in the
laws related to the fi sheries are weakly enforced allowing domestic and
Pacifi c Colombian sub-system:
foreign fi shing fl eets to avoid legislation. There is lack of institutional
Transfer of sustainable technologies;
cooperation, fi sheries statistics and stakeholder participation to aid and
Enhance information management and education programmes;
improve the eff ectiveness of decision making processes.
Further implement integrated coastal zone management (ICZM);
and
Policy options
Strengthen the self-regulation of coastal communities.
Recommendations made by the GIWA regional experts of the Eastern
Equatorial Pacifi c region coincide with those of international fora on
The countries of the Eastern Equatorial Pacifi c region are inextricably
water management and the Environmental Plan of Central America
linked by hydrological processes. Water is a vector transporting not
EXECUTIVE SUMMARY
11
only a wide variety of valuable resources but also problems from one
Plan of Action for the Protection of the Marine Environment and Coastal
country to another. In the Southwest Mexico sub-system, increased
Areas of the North East Pacifi c. The regional experts recognise that the
understanding of pollution issues, the establishment of communication
institutional inadequacies of water management need to be addressed,
networks between the stakeholders of a river basin, the creation of
and recommended the development of environmental awareness
incentives as well as penalties for polluters, and greater civil legal
programmes and the reorganisation of the water sector. To address the
powers will shift the political situation in favour of environmental
overexploitation of the fi sheries in the Pacifi c Colombian sub-system,
protection. In order to address transboundary pollution and freshwater
the regional experts recommended that the most feasible option would
scarcity in the Central Equatorial Pacifi c sub-system, a fi rst step would be
be to enhance information management and education programmes
the implementation of regional instruments of cooperation such as the
and to strengthen the self-regulations of local communities.
12
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Abbreviations and acronyms
ADD Acute
Diarrheic
Disease
IHP International
Hydrological
Programme
ANAM
Autoridad Nacional del Ambiente de Panamá
IIAP
Instituto de Investigaciones Ambientales del Pacífi co
BDO
Biological Degradable Organic
INDERENA Instituto de desarollo de los recursos naturales
BOD
Biological Oxygen Demand
renovables
CAC California
Current
INEGI
Instituto Nacional de Estadística, Geografía e Informática
CCA Causal
Chain
Analysis
INPA
Instituto Nacional de Pesca y Acuicultura
CCO Comisión
Colombiana
del
Océano
INVEMAR
Instituto de Investigaciones Marinas y Costeras
CNA
Comision Nacional del Agua
IPCC
Intergovernmental Panel on Climate Change
COCATRAM Central American Commission for Maritime
ISAT
Instituto de Salud, Ambiente y Trabajo
Transportation
ITCZ Intertropical
Convergence
Zone
COD
Chemical Oxygen Demand
IUCN
The World Conservation Union
CONADES National Council for Sustainable Development
LAC
Latin America and the Caribbean
CONAZA
Comisión Nacional de zonas Áridas
LME
Large Marine Ecosystem
CPPS
Comision Permanente del Pacifi co Sur
MARENA
Ministerio del Ambiente y los Recursos Naturales de
DANE
Departamento Administrativo Nacional de Estadística
Nicaragua
DDT dichlorodiphenyltrichloroethane
MARN
Ministerio de Medio Ambiente y Recursos Naturales
EEZ Exclusive
Economic
Zone
MINAE
Ministerio del Ambiente y Energía de Costa Rica
EPA
United States Environmental Protection Agency
MMA
Ministerio del Medio Ambiente
EU European
Union
MPN Most
Probable
Number
EUC Equatorial
Under-current
MSY Maximum
Sustainable
Yield
FAO
Food and Agriculture Organization of the United Nations
NEC
North Equatorial Current
FDA
Food and Drug Administration
NECC
North Equatorial Counter-current
GDP Gross
Domestic
Product
NEP
The Northeast Pacifi c Regional Seas programme
GIWA
Global International Waters Assessment
NGOs Non-Governmental
Organisations
GPA
Global Programme of Action for the Protection of the
ODECA
Central American States Organization
Marine Environment from Land-based Activities
OECD
Organisation for Economic Cooperation and
HABs
Harmful Algal Blooms
Development
HC Humboldt
Current
OMS
Organización Mundial de la Salud
ICA
Index of Water Quality
OPS
Organización Panamericana de la Salud
ICZM integrated
coastal
zone
management
PAHO
Pan American Health Organization
IDEAM
Instituto de Hidrología, Meteorología y Estudios
PARCA
Environmental Plan of Central America
Ambientales de Colombia
PC Peruvian
Current
IGAC
Instituto Geográfi co Agustin Codazzi
PCBs Polychlorinated
biphenyls
ABBREVIATIONS AND ACRONYMS
13
PNUD
Programa de las Naciones Unidas para el Desarrollo
TDSs Total
Dissolved
Solids
PNUMA
Programa de Naciones Unidas para el Medio Ambiente
TEDs Turtle
Exclusion
Devices
PSP
Paralytic Shellfi sh Poisoning
UNEP
United Nations Environmental Programme
SEC
South Equatorial Current
UNESCO
United Nations Educational, Scientifi c and Cultural
SEMAR
Ministry of the Navy
Organization
SEMARNAT Ministry of Environment and Natural Resources
USD
United States Dollar
SERNA
Secretary of Natural Resources and Environment
WCMC
World Conservation Monitoring Centre
SNET
Servicio Nacional de Estudios Territoriales
WFP
World Food Programme
14
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
List of figures
Figure 1
The boundaries of the GIWA Eastern Equatorial Pacific region and its sub-systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Figure 2
The ocean circulation in the Eastern Equatorial Pacific region. Surface currents (continuous arrows), subsurface currents (discontinuous arrows). . . . . . . . . . . . . 18
Figure 3
Surface run-off in the administrative districts of the Mexican Pacific sub-system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Figure 4
Drainage basins of the Eastern Equatorial Pacific. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Figure 5
Population of the countries in the GIWA Eastern Equatorial Pacific region. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Figure 6
Development of the population of the Colombia Pacific sub-system between 1995 and 2000, with a projection to 2020. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Figure 7
Drinking water coverage in the countries of the GIWA Eastern Equatorial Pacific region. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 8
Sanitation coverage in countries of the GIWA Eastern Equatorial Pacific region. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 9
Water availability per capita in the administrative districts of the Southwest Mexico sub-system.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 10
Water availability in the administrative districts of the Southwest Mexico sub-system.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 11
Fishing catches in the countries of the GIWA Eastern Equatorial Pacific region. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Figure 12
Annual discharges of five Mexican rivers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Figure 13
Annual discharges of Lempa River 1969-1974 and 1980. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Figure 14
The Central American drought corridor. Colours show the frequency of dry periods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Figure 15
Annual discharges of the San Juan River. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Figure 16
Annual discharges of the Patia River. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Figure 17
Remaining mangrove areas (in purple) in the Gulf of Fonseca. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Figure 18
Total catches of coastal marine resources in the Pacific Colombian sub-system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Figure 19
CCA diagram Freshwater shortage in the Central Equatorial Pacific sub-system.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Figure 20
Diagram showing the Causal chain analysis of microbiological and chemical pollution in the Central Equatorial Pacific and Central Mexican sub-systems. . . 54
Figure 21
Diagram of the Causal chain analysis of overexploitation in the Pacific Colombia sub-system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
List of tables
Table 1
Extent and distribution of the mangrove forests in the Pacific coast of Colombia. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Table 2
Monthly average discharges in rivers of the Colombian Pacific Basin. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Table 3
Discharges and draining areas of major rivers on the Pacific slope. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Table 4
Renewable hydric resources in the sub-system by country. Percent indicates the proportion respect to the entire sub-system.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Table 5
Scoring table for the Central Equatorial Pacific sub-system.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Table 6
Quality of the Lerma River according to physical, chemical and biological parameters 1990-2001.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Table 7
Quality of the Balsas River according to physical, chemical and biological parameters 1990-2001.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Table 8
Quality of the Chapala Lake according to physical, chemical and biological parameters 1990-2001.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Table 9
Total coliform (MPN/100mL) in major water bodies of the sub-system during the period 1991-2001. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Table 10
Wastewater, solids and nutrient discharges in the Central Equatorial Pacific sub-system by country.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Table 11
Coastal areas affected by pollution in the Central Equatorial Pacific sub-system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Table 12
Total and faecal coliforms at Tumaco and Buenaventura. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Table 13
Concentrations of nutrients in the Gulf of Nicoya. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Table 15
Concentrations of pesticides found in some marine species in Panama Bay. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Table 14
Concentrations of pesticides in the tissue of several species in Jiquilisco Bay, El Salvador. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Table 16
Concentrations of heavy metals found in sediments in several areas of the Central Equatorial Pacific sub-system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Table 17
Main activities affecting mangrove forests in the Pacific Colombian sub-system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Table 18
Total marine catches in the countries of the Central Equatorial Pacific sub-system. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Table 19
Different sceneries of global change in the Central Equatorial Pacific sub-system in 2100. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
List of boxes
Box 1
Immediate actions recommended by the Latin American Workshop on Wastewater Management. Mexico 10-12th September, 2001. . . . . . . . . . . . . . . . . . . . . . . . . . 57
Box 2
Fee-and-rebate system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
ABBREVIATIONS AND ACRONYMS
15
Regional defi nition
This section describes the boundaries and the main physical and
Boundaries of the Eastern
socio-economic characteristics of the region in order to defi ne the
Equatorial Pacific region
area considered in the regional GIWA Assessment and to provide
suffi
cient background information to establish the context within
The GIWA Eastern Equatorial Pacifi c region comprises the marine area
which the assessment was conducted.
and the basins of rivers draining into the Pacifi c Ocean along the west
coast of Central America, from Central Mexico in the north to the
Colombia-Ecuador border in the south (Figure 1). It includes parts
of Mexico, Guatemala, Honduras, Nicaragua, Costa Rica, Panama and
Rio Gra
nde de Sant GuGaudaalaja
d
ra
alaja
iago
Lake Chapala
MexicoToluca Puebla
s
Balsas
Balsa
Southwest Mexico
Guatemala
Honduras
Tegucigalpa
El Salvador
Gulf of
Fonseca
Nicaragua
es
Central Equatorial Pacific
cal
Tár
Pa
de
na
Elevation/
ma Cana
ande
Panama
Depth (m)
Gr
uí
x
Costa Rica
l
iq
li
ir
e
h
F
C
Panama
4 000
San
2 000
1 000
500
n
100
Jua
0
Colombia San
-50
Pacific Colombian
-200
-1 000
Patia
M
-2 000
ira
0
500 Kilometres
Ecuador
© GIWA 2005
Figure 1
The boundaries of the GIWA Eastern Equatorial Pacifi c region and its sub-systems.
16
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Colombia, and all of El Salvador. The marine area includes the Tres Marías
some 25% of Mexico's total area. The marine area is infl uenced by the
Islands at its northern limit. The marine boundary of the region is based
cold California Current from the north and a branch of the warm
on the criteria used to defi ne the Large Marine Ecosystems (LME) of
Equatorial Current from the south. The interaction of these currents
the Equatorial Pacifi c the Humboldt Current and California Current
produces an active marine area. Major geographic features include the
(Sea Around Us Project 2002). The land boundary is mostly an arbitrary
Gulf and Ithmus of Tehuantepec in the south of the sub-system and the
line based on diff ering historical and economic development, and
Revillagigedo archipelago in the northwest.
population occupancy between the Caribbean and the Pacifi c zones
of the Central American countries (PNUD/EU 1998); in the southern part
The Central Equatorial sub-system includes the western part of the
of Colombia, it is taken as the west Andean mountain branch, which
Central American isthmus, which is fl anked to the east by the Caribbean
physically divides that country. The Gulf of Fonseca is an important
Sea and to the west by the Pacifi c Ocean. It includes the coastal and
transboundary feature of the region shared by three countries, El
marine areas of six countries (Costa Rica, El Salvador, Guatemala,
Salvador, Honduras and Nicaragua. There are minor transboundary
Honduras, Nicaragua and Panama) with 3 870 km of coastline. It
rivers along the borders of several countries, as well as important
extends from the Guatemala-Mexico border in the north to the
national rivers that have transboundary impacts in the coastal zone.
Panama-Colombia border in the south (Figure 1). The total coastal area
infl uenced by the Pacifi c Ocean is estimated to be 150 300 km2 (PNUMA
The environmental characteristics of the Central American countries
2001). The sub-system's continental area is characterised by a mountain
(Guatemala, Honduras, El Salvador, Nicaragua, Costa Rica and Panama)
range with two orographic systems an older range in Guatemala,
are similar, and show distinct diff erences to Mexico and Colombia. For
Honduras and Nicaragua and a younger one in Panama and Costa Rica,
example, Colombia is among the six countries that possess over half
extending through the southeastern part of Nicaragua.
of the global surface water resources (Tierramerica 2004), whereas
water is scarce in most Central American countries. The environmental
The Pacifi c Colombian coast is fl anked by the Panama Bight in the
problems of Mexico and Colombia are also diff erent because of
Eastern Tropical region of the Pacifi c Ocean (Steer et al. 1997). It
their higher levels of industrialisation and urbanisation. Taking these
extends for 1 300 km from Colombia's border with Panama at Jurado
diff erences into account, the regional experts considered it appropriate
in the north to its border with Equador near the outlet of the Mira River
to divide the region into three sub-systems the Mexican Southwest
at Cape Manglares in the south (Figure 1) (Prahl et al. 1990, Restrepo &
Pacifi c, Central Equatorial Pacifi c, and Pacifi c Colombian sub-systems
Kjerve 2000). It includes the islands of Gorgona, Gorgonilla and Malpelo
(Figure 1). Because of the lack of signifi cant transboundary issues in
(Steer et al. 1997). Its land area is 23 500 km2 around 2% of Colombian
the Southwest Mexico and Pacifi c Colombian sub-systems, detailed
territory. Its oceanic area is 339 500 km2.
Assessment and Causal chain analysis have been focused more on the
Central Equatorial Pacifi c sub-system.
Climate
The climate of the Southwest Mexico sub-system is strongly infl uenced
by tropical anti-cyclones of the northern hemisphere. The area is sub-
humid to temperate sub-humid with temperatures higher than 26°C
Physical characteristics
along most of the coastal zone, dropping to between 18 and 21°C
during the coldest months (Amendola et al. 2005). The sub-system
The countries of the Eastern Equatorial Pacifi c region have several
receives over 800 mm of rainfall and even more in the southernmost
environmental features in common. These include extensive coastal
part in Chiapas, although it decreases steadily towards the highlands.
areas in the Pacifi c basin, unevenly distributed water resources and
The rainy season is monsoonal in summer with convective rain.
vulnerability to recurrent and extreme natural events, such as hurricanes
and the El Niño phenomenon.
The climate of the Central Equatorial Pacifi c sub-system is tropical to
temperate with a variable dry period during the winter (Ofi cina de
The Southwest Mexico sub-system includes seven coastal states
Coordinación Plan Puebla-Panama 2001). Conditions vary latitudinally.
(Nayarit, Jalisco, Colima, Michoacan, Guerrero, Oaxaca and Chiapas)
There is a dry zone, named by the FAO as the drought corridor,
along 1 800 km of the Pacifi c coast of Mexico. The sub-system stretches
extending from Guatemala to the northern part of Costa Rica that
from the border between the states of Nayarit and Sinaloa in the north
experiences drought for at least fi ve months of the year. There are also
to the border with Guatemala in the south. It covers about 500 000 km2,
dry areas in Panama the dry arc of Azuero. There is a high humidity
REGIONAL DEFINITION
17
transition zone in Guatemala and a rainy zone in the south of Costa Rica
Equatorial under-current; the Peruvian Current, the coastal branch of
and Panama with dry periods of two months (Windevoxhel et al. 2000,
which fl ows northward along the Pacifi c Colombian coast; and the
WFP/FAO 2002). Other vulnerable zones include the dry arc of the Gulf
northern extension of the Humboldt Current (PNUMA 2001).
of Fonseca on the Nicaraguan coast and some dry areas in the Paz River
basin of El Salvador. The region is vulnerable to El Niño events, when the
The interaction of these currents, their diff erent types of water and their
Pacifi c side of Central America receives abnormally little rainfall causing
related gyres, results in a very active marine area. There are upwelling
intense drought conditions, whereas the Caribbean side experiences a
zones along the coasts of Panama, and smaller ones along the coast
stronger rainy season (PNUD/EU 1998).
of Central America and off shore on the Costa Rica Dome. Upwelling in
the northern coastal areas is particularly intense. These characteristics
The Columbian Pacifi c sub-system is wet tropical and infl uenced
strongly infl uence the abundance and distribution of fi shing resources
by the Intertropical Convergence Zone (ITCZ), its proximity to the
and other coastal marine biota. The Costa Rica Dome, located between
ocean and by climatic events such as the El Niño. The ITCZ is a zone
8° and 11° N and 85° to 94° W, is a major ocean feature. It infl uences an
of low atmospheric pressure, where northeast and southeast trade
area some 400 km in diameter especially between January and March.
winds converge to create thermodynamic conditions that favour the
In this zone, the wind drives water to a depth of 1 250 m where it
development of clouds and rain; southeast trade winds defl ect along
moves towards the western tropical circulation, producing a nutrient-
the coast and become western equatorial or westerly winds (INVEMAR
rich upward fl ow (PNUMA 2001). The upwelling combined with coastal
2003a). Heavy rainfall occurs throughout the year (INVEMAR 2003a).
run-off stimulates moderately high productivity (150-300 g C/m2/year)
Rainfall peaks twice in April-June and September-November and is
(FAO 1997). The upwellings are also infl uenced by winds blowing from
lowest in January-March (INVEMAR 2003a).
the Caribbean Sea, the areas of upwelling coinciding with the three
major mountain ranges of the region (Sea Around Us Project 2002).
The marine area
The marine area of the Eastern Equatorial Pacifi c region is infl uenced by
The coastal area
three major current systems the California Current from the north, the
The coastal belt of the Southwest Mexico sub-system ranges from
Humboldt Current from the south and the Equatorial Counter-current
mountainous with rocky shores to coastal plains with some extensive
from the west. The California Current covers the northern coastal region
lagoons and barrier beaches. There are 13 lagoon systems with
as far as the northwestern tip of El Salvador, distributing cold-temperate
abundant forests including mangroves. In the marine area of the
waters (Croom et al. 1995, PNUMA 2001). The North Equatorial Counter-
sub-system there are several coral reefs of biological importance. The
current transports warm water into the region, branching north and
Revillagigedo archipelago is located 700 km off shore and constitutes
south off Costa Rica, forming northward anti-cyclonic and southward
the westernmost feature of the region.
cyclonic gyres (Figure 2). The southern part of the region is infl uenced
by waters from diverse origins the Southern Equatorial Current; the
The coast of the Central Equatorial Pacifi c sub-system is characterised by
peninsulas, gulfs and bays. There are extensive intertidal areas, barriers
and coastal lagoons. Short rivers discharge signifi cant volumes of
freshwater and suspended solids into the Fonseca Gulf during the rainy
California Current
season between May and September (Croom et al. 1995, Windevoxhel
North Equatorial Current
et al. 2000). Mangrove forests occupy the alluvial plains of the Chanturo-
Teculapa-Panzacola river systems along most of 300 km of coastline
North Equatorial Counter-current
extending southeastwards from near the border with Mexico (Florez-
Verdugo et al. in Croom et al. 1995). Most of the Gulf of Panama coast is
Equatorial Under-current
fl at with small rivers and estuaries, swamps and mangroves; there are
South Equatorial Current
extensive salt marshes to the west of the Panama Canal.
Peruvian
Current
Subsurface currents
Humboldt Current
The northern coast of the Pacifi c Colombian sub-system is mountainous
Surface currents
with ravines and cliff s, whereas the southern coast is fl at with sandy
Figure 2
The ocean circulation in the Eastern Equatorial
beaches, mangrove areas and extensive estuaries formed by numerous
Pacifi c region. Surface currents (continuous arrows),
subsurface currents (discontinuous arrows).
rivers such as San Juan and Patia. Rocky coasts and cliff s form 287 km
18
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
of the northern coast at the foothills of the Baudo mountain range
muddy and sandy bottoms between 0 and 40 m depth, including
(Martínez in INVEMAR 2003a). South of Cape Corrientes, cliff s are
crabs (Callinectes arcuatus) and some species of shallow water shrimp
discontinuous along the outlet of the San Juan River, Malaga Bay,
(Pineda-Polo 1992, Pineda et al. in INVEMAR 2003a).
Buenaventura Bay and the Gulf of Tortugas (INVEMAR 2003a). There
are several sandy beaches on the northern coast, such as Solano Bay,
There are 12 species of mangrove in the region. Mangroves are abundant
Humboldt, Aguacate, Coredo, Ardita, Nabuga and Guaca. On the
in protected areas, particularly in Mexico, Panama, Colombia and the
southern coast, beaches comprise sandy-muddy sediments originating
Gulf of Fonseca in Costa Rica (PNUMA 2001). Three countries, Colombia,
from river discharges, as at Baudo, San Juan, Dagua, Anchicayá, Naya,
Panama and Mexico, account for about 80% of the total coverage. Using
Patía and Mira (Cantera & Arnaud 1995, Martínez in INVEMAR 2003a).
radar images and air photos, Zambrano & Rubiano (1996) estimated
At the mouths of the major estuaries there are important low-lying
the area of mangrove cover on Colombia's Pacifi c coast to be 2 930 ha
sandy islands (Martínez in INVEMAR 2003a). The main coastal lagoons
(Table 1) (Informe de República de Colombia et al. 2002).
and estuaries are those formed by deltas of rivers, such as Jurado and
Partado, Catipre, Baudó, San Juan, San Juan de Micay, Guapí, Patía, and
There are 15 wetlands of international importance in the region,
bays, such as Tumaco, Málaga and Buenaventura.
together covering an area of 640 857 ha. Eleven of these are coastal
(PNUMA 2001). Costa Rica has seven Ramsar sites in its Pacifi c coastal
Biodiversity
area (218 087 ha); Nicaragua, three (98 530 ha); Panama, two (94 570 ha);
Coastal upwelling inhibits the development of coral reefs (PNUMA/
and the remaining countries, one each Mexico (144 866 ha), Guatemala
IUCN 1988). The reefs that do occur are small and discontinuous, and
(13 500 ha), Honduras (13 850 ha) and El Salvador (1 517 ha). There are
less abundant than those of the Caribbean coasts of Central America
numerous highly productive and biologically diverse estuaries and
(Glynn & Wellington 1983). Fifteen species of coral have been reported
lagoons in the region. El Salvador has more than 30 lagoons; Honduras
as the most common in 42 important sites (PNUMA 2001), the greatest
is characterised by lagoons no more than 5 m deep; and lagoons occur
diversity occurring in Mexico, Costa Rica and Colombia. On the
also in Nicaragua and Costa Rica and in the south of Colombia (PNUMA
Colombian coast, small coral reefs include the corals Pocillopora sp.,
2001). There are few large islands in the region but over 180 small islands
Pavona, Porites, Psammocora and Gardineroseris planulata. On some
(e.g. Coiba, Otoque and Perlas). Beaches, dunes and cliff s are common;
isolated rocky shores (Capes Corrientes and Marzo) coral colonies
several beaches are important turtle nesting sites (Escobar 2005). In the
develop together with other sessile invertebrates, such as barnacles,
Pacifi c Colombian sub-system, there are three protected areas the
octocorals and sponges, although they do not form true coral reefs.
National Parks of Sanquianga (80 000 ha); Gorgona (61 687 ha), which
The presence of true coral reefs is directly determined by the availability
includes the islands Gorgona and Gorgonilla and their surrounding
of hard substrates and clear waters, away from river discharges and
marine area; and Utria (54 300 ha), which includes a marine area of
estuarine ecosystems with mangroves. According to their geographic
12 000 ha (INVEMAR 2003a).
distribution in relation to the continent, these communities are classifi ed
in three groups the barrier reefs of the continental coast of North
In the Pacifi c Colombian sub-system, there are several types of forest
Choco (Utría Cove and Cupica Bay), the barrier reefs of the continental
community including Tropical Wet Forest, Tropical Highly Wet Forest,
Gorgona island, and the barrier reefs of the oceanic Malpelo island
Tropical Pluvial Forest, Pre-mountain Pluvial Forest, Low Mountain
(INVEMAR 2003a). The Central Equatorial Pacifi c sub-system's coastal
Pluvial Forest and Low Mountain Highly Wet Forest (INVEMAR 2003a).
waters and continental shelf include habitats for several species of
economically important crustaceans. Some of these species inhabit
Hydrology
The hydrology of the region has been described by UNEP (2001). In
Table 1
Extent and distribution of the mangrove forests in the
the Southwest Mexico sub-system, the major river basins include the
Pacifi c coast of Colombia.
Lerma-Santiago, Ameca and Balsas. Another basin, River Suchiate,
Region
Department
Area (ha)
%
is shared with Guatemala. Rainfall between 1941 and 2000 showed
Cauca
36 276.8
9.57
important seasonal variations among the diff erent administrative
Choco
64 750.5
17.08
Pacific
districts on the southern Pacifi c slope (CNA 2002). In general, more
Nariño
149 735.8
39.50
than three-quarters of the rainfall occurs over the fi ve months June to
Valle del Cauca
41 961.4
11.07
October, with a noticeable dry period between February and April. The
Subtotal
292 724.5
100.00
(Source: Zambrano and Rubiano, 1996; 1997, in: INVEMAR, 2003a)
South Border district has the highest rainfall, whereas Lerma-Santiago
REGIONAL DEFINITION
19
and Balsas districts have the lowest. The average annual rainfall in
Panama Canal Basin
South Border is 2 260 mm; South Pacifi c, 1 130 mm; Balsas, 800 mm and
Lerma-Santiago, 670 mm. On the Southwest Mexico slope the average
annual surface run-off is 260 km3. The South Border district accounts for
140 km3 (54%) of the total; Balsas, 24 km3; Lerma-Santiago, 32 km3; and
South Pacifi c, 32 km3 (Figure 3). The annual groundwater recharge on
the Pacifi c slope is 36 km3. The largest proportion of this recharge occurs
in South Border (17 km3), with smaller volumes in Lerma-Santiago, 7.1
km3; Balsas, 4.9 km3; and South Pacifi c, 1.7 km3.
160
140
0
500 Kilometres
© GIWA 2005
120
Figure 4
Drainage basins of the Eastern Equatorial Pacifi c.
m³)
(k
100
50% of the country. Transboundary rivers include the Paz, shared with
80
Guatemala, and the Gosgocaran, shared with Honduras. Honduras has
60
a total surface run-off of 87 km3/year, 13% of which discharges into the
Surface runoff
40
Pacifi c via the Gulf of Fonseca. Its transboundary rivers include the
20
Gosgocaran, and the Negro, shared with Honduras. Nicaragua has eight
0
Balsas
South Pacific
Lerma-Santiago
South Border
river basins with short rivers (<20 km) on the Pacifi c slope; the Negro
Administrative region
River being shared with Honduras; there are no transboundary rivers
Figure 3 Surface
run-off in the administrative districts of the
on its border with Costa Rica within the region. In Costa Rica, there are
Mexican Pacifi c sub-system.
(Source: CAN 2002)
no transboundary rivers inside the boundaries of the region. Similarly
in Panama, there are no transboundary rivers within the region; the
In the Central Equatorial Pacifi c sub-system, although water resources
Panama Canal basin contains the most important aquifers.
are generally abundant due to the proximity of the sub-system to the
ITCZ, they are unevenly distributed. According to FAO (2004a), Panama
In the Pacifi c Colombian sub-system, there are vast surface water
receives the highest average annual rainfall at 3 100 mm (in the range
resources in fi ve hydrologic regions. In 1979, average rainfall was around
1 100-5 500 mm). Costa Rica's annual average in the region is 1 400-
3 000 mm, twice the average of the rest of South America and three
2 500 mm; Nicaragua's, 500-2 000 mm; El Salvador's, 1 400-2 400 mm;
times the world average (UNESCO in Marín 1992). The major surface
and Guatemala's, 5 000 mm in the northwest but only 700 mm in the
water resources on the Pacifi c slope are the rivers Patía, San Juan, Mira,
dry western area (near El Salvador and Honduras). Rivers discharging
Micay, Dagua, Anchicaya and Guapi (Tables 2 and 3). The Mira River
to the Pacifi c are generally dynamic, short with steeply sloping profi les
Table 2
Monthly average discharges in rivers of the Colombian
(Figure 4); they transport high sediment loads, especially during
Pacifi c Basin.
the rainy season (May-November). Several rivers discharge through
River
Station
Minimum (m³/s)
Maximum (m³/s)
Annual average (m³/s)
estuaries forming coastal wetlands (PNUMA 2001). The sub-system
San Juan
San Juan
March: 1 570
November: 2 740
2 060
contains extensive lakes with surface areas totalling 17 700 km2.
Micay
Angostura
July: 125
October: 472
132
Nicaragua has the greatest lake cover (59%) with the two major lakes
Patia
Pusmeo
September: 170
December: 488
-
of Central America, Xolotlán (1 053 km2) and the Nicaragua or Cocibolca
(Source: INVEMAR 2003)
Lake (8 144 km2). In Guatemala there are 23 lakes and 119 lagoons
Table 3
Discharges and draining areas of major rivers on the
covering 950 km2, while Honduras includes El Yojoa Lake (90 km2).
Pacifi c slope.
River
Station
Area (km²)
Discharges (m³/s)
Guatemala's surface water run-off to the Pacifi c amounts to 26 km3/year.
San Juan
Malaguita
15 180
2 600
Two Guatemalean rivers discharge through neighbouring countries the
Patia
Pusmeo
14 162
346
Suchiate in Mexico and the Paz in El Salvador. El Salvador has 180 rivers;
Micay
Angostura
2 511
280
the Lempa River forms the major hydrological system, covering some
(Source: PMNR/MMA/IGAC 1999. Ecologic Zoning of the Colombian Pacific Region Project.)
20
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
basin is shared with Ecuador. The sub-system contains the rivers with
km2 (100%). About 80% of the population live in Colombia and Mexico
the highest fl ows in Colombia, the average surface run-off on the Pacifi c
(Figure 5). In 2002 the proportion living in urban areas was 57% (WRI
slope being 6 900 m3/s. There are no lakes along the Pacifi c Colombian
2004). The population of the region increased at an annual rate of 2.2%
coast except the Trueno Lagoon at Payan, Nariño. There are swamps in
during the period 1995-2000. It is expected that the rate will decrease
the Choco and Cauca departments but little information about them
to 2% during the period 2000-2005.
is available (INVEMAR 2003a).
There are four administrative districts Balsas, South Pacifi c, Lerma-
Santiago-Pacifi c and South Border.
Socio-economic characteristics In the Central Equatorial Pacifi c sub-system, the population has
increased by 98% from 19.3 million to 37.7 million between 1975 and
The countries of the Eastern Equatorial Pacifi c region share critical
2002. Over the same period the population density increased from
environmental problems related to development. These include poor
39 inhabitants/km2 to 66 inhabitants/km2. The population occupies
levels of wastewater treatment and sanitation coverage, low levels
only a quarter of the sub-system's territory with 70% inhabiting the
of drinking water service, overpopulation, the overexploitation and
Pacifi c slope. The urban area is 596 km2, which is 0.09% of the sub-
depletion of natural resources as well as habitat destruction. Although
system's total. If current urbanisation trends continue, the urban area
countries in the region have diff erent degrees of development, all of
is expected to cover 913 km2 by 2030. Urban populations increased
them face problems related to poverty. Countries have a high rate of
by 29% over the period of 1975-2000, from 35.3% in 1975 to 56% in
population growth and are experiencing urbanisation.
2000. About 75% of the population will live in urban areas by 2030 as a
consequence of natural population growth, longer life expectancy and
The region is rich in natural resources on which its economy is highly
migration from rural areas.
dependant, either directly for exploitation, as in the cases of fi shing,
forestry and mining, or indirectly, e.g. for ecotourism. Mexico and
The total population of the Pacifi c Colombian sub-system was
Colombia have a higher level of industrialisation, however, in most of
7.8 million people in 2003; approximately 18% of the national population
the countries agriculture plays an important social and economic role.
(estimates based on data from DANE 2001). Its growth rate is slightly
lower than the national average (Figure 6). Its proportion of the national
The region's population increased between 1975 and 2002 from
population will reduce from 18% to 17% between 1995 and 2020 and its
80.8 million to 180.3 million people (111.6%) (Figure 5). During the
population growth rate will reduce from 2% to 1% over the same period.
same period, the population density increased from 51 to 102 people/
It is estimated that by 2020 the coastal population will reach 9.9 million
people (DANE 2001). According to the national census, except for the
100
inhabitants of the Valle del Cauca department, the population of the
Nicaragua
Costa Rica
Honduras
2.7%
2.0%
Panamá
sub-system is predominantly rural. It is employed mostly in agriculture
3.5%
80
1.6%
El Salvador
3.6%
Guatemala
12 000 000
60 000 000
60
6.5%
(millions)
10 000 000
50 000 000
México
C
tion
olombia
40
56.2%
Colombia
8 000 000
40 000 000
pula
23.9%
o
acific
P
P 6 000 000
30 000 000
20
Pacific population
4 000 000
20 000 000
Colombia population
0
2 000 000
10 000 000
o
á
ica
m
éxic
mala
a
0
0
n
M
lombia
e
1995
2000
2005
2010
2015
2020
o
Pa
C
i
caragua
osta R
Guat
Honduras
El Salvador
N
C
Year
Country
Figure 6
Development of the population of the Colombia Pacifi c
Figure 5
Population of the countries in the GIWA Eastern
sub-system between 1995 and 2000, with a projection
Equatorial Pacifi c region.
to 2020.
(Source: GIWA Task team)
(Source: DANE 2002, GIWA Task team)
REGIONAL DEFINITION
21
(22%), trading (15%) and manufacturing industries (10%). In the Choco
In the Southwest Mexico sub-system in 2001, the natural availability of
department, mining provides 23% of the employment, manufacturing
water on the Pacifi c slope was about 294 km3, 62% of the total reported
in the Valle del Cauca, 12%, and fi shing in the Nariño department, 2%.
for Mexico as a whole (472 km3). The South Border administrative district
accounts for one-third of the total available water of the country
Water supply and sanitation
(156 km3) or 53.1% of the Pacifi c slope. Other districts within the sub-
The provision of water services surpasses the average population
system include Lerma-Santiago, 39.5 km3 (13%), South Pacifi c, 33.1 km3
coverage of the Americas (82.9%) in only two countries in the region
(11%), and Balsas, 28.2 km3 (10%) (Figure 9). South Pacifi c and South
Costa Rica (89%) and Mexico (85%). Three countries are below the
Border districts had water availability values of 8 344 and 26 791 m3/
average population coverage for Latin America and the Caribbean (LAC)
inhabitant/year respectively, representing an abundance of water, while
Guatemala (62%), Nicaragua (54%), and El Salvador (52%). Countries
the more populated districts such as Balsas and Lerma-Santiago had
with the lowest access to drinking water provide alternative supply
values of 2 844 and 2 084 m3/inhabitant/year, respectively, representing
services called `easy access' (access to a public source of water other than
freshwater shortages (Figure 10).
the pipeline connection). Countries with the largest proportion of their
population relying on easy access drinking water are Guatemala (19%),
In the Southwest Mexico sub-system, gross water extraction from the
Colombia (15%), and Nicaragua (12%). Figure 7 and 8 show the level of
Pacifi c slope in 2000 was 44.7 km3, notably in the Lerma-Santiago dis-
drinking water and sanitation coverage in the countries of the region.
trict (15 km3). Extractions in the other districts were Balsas, 7.7 km3,
South Pacifi c, 1.6 km3 and South Border, 1.8 km3. While South Border
100
district had the highest available water resources on the Pacifi c slope,
Without service
90
14.5%
"Easy access"
extraction there was the lowest. According to CNA (2002), 83.4% of
80
6.8%
With connetion
70
60
30 000
78.8%
(million)
50
tion
25 000
40
opula
30
20 000
P
20
(m³/capita)
y 15 000
10
0
a
10 000
ica
ailabilit
x
i
c
o
m
mala
a
v
n
A
Me
lombia
e
ion 65
o
sta R
Pa
g
5 000
C
i
caragua
o
e
Guat
Honduras
El Salvador
N
C
A r
Country/Region
GIW
0
Balsas
South Pacific
Lerma-Santiago
South Border
Figure 7
Drinking water coverage in the countries of the GIWA
Administrative region
Eastern Equatorial Pacifi c region.
(Source: GIWA Task team)
Figure 9
Water availability per capita in the administrative
districts of the Southwest Mexico sub-system.
100
(Source: CNA 2002)
Without service
90
In situ
80
23.8%
180
With connection
70
53.4%
160
22.7%
60
140
(million)
m³)
50
(k
120
tion
y
40
100
opula
30
P
ailabilit
80
20
v
60
10
t
er a
a
W
40
0
ica
20
x
i
c
o
mala
nama
Me
lombia
e
a
ion 65
o
sta R
P
g
0
C
i
caragua
o
e
Guat
Honduras
El Salvador
N
C
Balsas
South Pacific
Lerma-Santiago
South Border
A r
Country/Region
GIW
Administrative region
Figure 8
Sanitation coverage in countries of the GIWA Eastern
Figure 10 Water availability in the administrative districts of the
Equatorial Pacifi c region.
Southwest Mexico sub-system.
(Source: PAHO 2001)
(Source: CNA 2002)
22
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
water use on the Pacifi c slope in 2000 was for agriculture.
Table 4
Renewable hydric resources in the sub-system by country. Percent
Most of the demand for water for agricultural use comes
indicates the proportion respect to the entire sub-system.
from the Lerma-Santiago district (11.5 km3), of which 56% is
Average
Recharge
Total water
Surface water
Total water
Volume per
rainfall
underground
resources
produced
resources
from surface water and 44% groundwater. In the south of
Country
capita 2002
1961-1999
water
1997-2000
(m³)
the sub-system, volumes of water used for agriculture are
(mm/year)
km³
%
km³
%
km³
%
km³
%
lower; 1.1 km3 in South Pacifi c and 1.0 km3 in South Border.
Costa Rica
2 926
75
12.2
37
26
112
16.6
112
16.2
26 764
Urban water consumption is highest in the Lerma-Santiago
El Salvador
1 724
18
2.9
6
4.2
18
2.67
25
3.6
3 872
district at 1 606 km3, of which 1 207 km3 is from ground-
Guatemala
2 712
101
16.5
34
24
109
16.2
111
16.1
9 277
water and 399 km3 from surface sources (CNA 2002). The
Honduras
1 976
87
14.2
39
27.5
96
14.2
96
13.9
14 250
demand in Balsas district is 800 km3 (68% from groundwa-
Nicaragua
2 391
186
30.4
59
41.5
190
28.2
197
28.5
36 784
ter); in South Border, 485 km3 (181 km3 groundwater); and
Panama
2 692
144
23.5
21
14.7
147
21.8
148
21.4
50 299
in South Pacifi c, 323 km3 (160 km3 groundwater). Industrial
Sub-system
2 403
611
100
142
100
672
100
689
100
23 541
Source: FAO (2002 a , and 2004a) and WRI (2004).
use is greatest in Lerma-Santiago at 1 233 km3 (around 66%
groundwater); the demand in Balsas is 480 km3 (around 66%
groundwater); South Border, 286 km3 (57% groundwater);
The Panama Canal basin covers 5 527 km2 6.5% of Panama's total area
and South Pacifi c, 114 km3 (89.6% groundwater).
(Figure 4). According to Castro (2003), the basin includes two major
components the traditional basin and the western basin. The
In the Central Equatorial Pacifi c sub-system, there are more than
former covers 3 397 km2 and includes the river basins of the Chagres
81 basins draining to the Pacifi c, discharging a total volume of 672 km3
(northbound fl ow to the Caribbean) and Grande (southbound fl ow to
annually (FAO 2004a). Panama and Nicaragua produce half of the
the Pacifi c), forming a unique navigation system through the Galliard
surface water in the sub-system and Panama has the highest water
Cut, excavated between 1904 and 1914. This system includes the Gatún
availability 50 300 m3/inhabitant/year. Groundwater constitutes a
Lake and the Alajuela Lake, built as an additional water reserve in the
major resource for agriculture, industry and domestic consumption
upper basin of the Chagres River after the construction of the Madden
(Table 4). Three of the most important basins are described below.
dam. The western basin covers 2 131 km2 and includes the river basins of
the Coclé del Norte, Indio and Caño Sucio, all of which discharge into the
The Lempa River basin covers 18 311 km2, shared by El Salvador (56%),
Caribbean Sea. The Panama Canal, about 80 km long, crosses the basin.
Guatemala (14%) and Honduras (30%) (CCAD 2002). It is transboundary
Each vessel traversing the Canal uses 197 million litres of freshwater,
in nature, and embraces 45 municipalities with a total population in
which fl ows through fl oodgates to the ocean (Vargas 1998).
2001 of 4.7 million people. This is around 13% of the sub-system's total
population. The Lempa River is 335 km long and is the main source of
Economic activity
freshwater for El Salvador (72% of that country's total surface water).
According to UNEP (2001), during the period 1994-1998 agriculture was
The River also generates 65% of the country's electricity through three
the main economic activity in the region accounting for 20% of Gross
hydroelectric plants. Although the mid- and lower parts of the basin are
Domestic Product (GDP). Countries with higher rates include Nicaragua
in El Salvador, upstream activities have important implications for the
(34%), Guatemala (23%) and Honduras (22%). Agriculture provides
whole basin (Artiga 2002).
employment for around half of the economically active population.
The major export products include coff ee, bananas and sugar.
The Grande de Tarcoles River basin in Costa Rica covers 2 156 km2,
around 4% of the country. Although only 88 km long and 36 km wide,
Historic and current fi sh production is mainly based on pelagic fi sheries
it contains 53% of the Costa Rican population as well as the capital, San
and, to a lesser extent, squid, shrimp and coastal demersal species (FAO
José. The basin is the location of 85% of the country's industry, trading
1997). Of the total catches in the region in 1997, Mexico accounted for
and services. Its main aquifers, Barva and Colima, supply freshwater to
77%, with Panama and Colombia, 11% and 9% respectively (Figure 11).
66% of the urban population (the cities of San José, Heredia, Alajuela). Its
Coastal and artisanal fi sheries have a high socio-economic signifi cance;
catchment includes pastureland (29%) and woodland (18%) (Ballesteros
around half a million fi shermen and processing plant operators are
2003). Although the basin lies entirely within Costa Rica, its drainage
employed in the industry and in some communities the fi sheries are
has transboundary impacts on the coastal waters of the Pacifi c Ocean.
the only source of employment. Aquaculture is a growing industry
in the region, particularly shrimps (Lithopenaeus spp.) and, on a small
REGIONAL DEFINITION
23
Regional cooperation
Catch (thousand tonnes)
0
200
400
600
800
1000
1200
The countries in the region have adopted several legal mechanisms that
Mexico
aim to strengthen regional cooperation regarding the management of
Panamá
water. However, not every country in the region is party to the same
Colombia
Nicaragua
0.4%
conventions and agreements. The cooperation mechanisms listed
y Costa Rica
Panama
10.6%
below mainly involve the countries of the Central Equatorial Pacifi c sub-
Mexico
untr
Colombia
o Honduras
77.6%
C
9.2%
system. Mexico has stronger ties with the North American countries and
Costa Rica
Nicaragua
1.4%
has maintained bilateral agreements on water with the United States
El Salvador
El Salvador
Honduras
0.3%
since the beginning of the 20th century. Panama and Colombia have also
0.5%
Guatemala
Guatemala
0.0%
ratifi ed the Convention for the Protection of the Marine Environment
0
20
40
60
80
100 120 140 160
and Coastal Area of the South-East Pacifi c (Lima Convention), adopted
Catch (thousand tonnes)
1981, and the complementary protocols (see Annex III). In addition to
Figure 11 Fishing catches in the countries of the GIWA Eastern
those given below, other important initiatives concerning water issues
Equatorial Pacifi c region.
in the Central Equatorial Pacifi c sub-system include the Dialogue on
(Source: Sea Around Us Project 2002)
Water, Food and Environmental Sustainability, San Jose, Costa Rica
scale, molluscs and fi sh. In Central America, 70% of the total aquaculture
(2001), and the Central American Summit on Sustainable Development,
production comes from Honduras and Panama. The United States
Nicaragua (1994) (Annex III).
imports about 95% of the cultured shrimp exports. In the Central
Equatorial Pacifi c sub-system, fi sheries production is dependent on
The Northeast Pacifi c (NEP) Regional Seas programme
the upwelling of nutrient-rich ocean waters, as at Papagayo (Costa
In response to the Central American Governments' call for more
Rica), and, to a lesser extent, the fi shing grounds supported by nutrient
collaborative environmental mechanisms at a Meeting of Experts in
run-off (PNUMA 2001).
1996, the decision was taken in 1997 to incorporate the countries of the
Northeast Pacifi c into its Regional Seas Programme. On 18th February
Tourism has a growing economic importance in the region, which has
2002, the Convention for the Protection and Sustainable Development
many attractions including traditional modalities (sun and beaches)
of the Marine and Coastal Environment for the Northeast Pacifi c
and emerging opportunities (ecotourism and agrotourism). Tourism
(Antigua Convention) was signed by six of the member countries (Costa
accounts for around 30% of GDP, making it the region's second most
Rica, El Salvador, Guatemala, Honduras, Nicaragua and Panama), with
important economic activity. According to the Central American
Colombia and Mexico expressing an interest to sign. The Plan of Action
Institute of Tourism, the numbers of tourists in most countries in 2000
of the Convention (Action Plan) was also adopted by the six member
exceeded 500 000. Costa Rica received 26% of the total number of
countries as well as Colombia and Mexico on 18th February 2002 in La
visitors to Central America.
Antigua, Guatemala.
Except in Colombia and Mexico, industry is underdeveloped,
The main objective of the Plan of Action is to provide a regional
contributing only 15% to the regional GDP. There is intensive
cooperative framework for promoting and facilitating the sustainable
commercial and tourist shipping throughout the region including
management of the marine and coastal resources of the countries of the
an intercontinental maritime route. The most signifi cant location
northeast Pacifi c for the well-being of the present generation and future
for maritime traffi
c is the Panama Canal, where during 1990-1998 an
generations in the region. The Action Plan spans the area between the
average of 14 300 ships passed every year, generating an income of
extreme south of the Pacifi c seaboard of Colombia, where it borders
420.3 million USD (PNUMA 2001). Mining of the region's rich mineral
Ecuador, to the extreme north of Mexico on the Pacifi c, at its border
resources produces signifi cant proportions of the world's totals silver
with the United States. The region comprises what is known as the Great
(18%), lead (6%), copper (3%), zinc (5%), gold (2%), nickel (3%) and tin
Marine Ecosystem of the California Current.
(1%) (PNUMA 2001). Activities relating to oil include transportation,
storing and refi ning. There are no off shore platforms in the region.
COCATRAM
The Executive secretariat for NEP is hosted by the Central American
Commission for Maritime Transport (COCATRAM) in Guatemala.
24
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
COCATRAM is part of the Central America Integration System (SICA in
Central American Commission on Environment and
Spanish). The objective of COCATRAM is to look at issues relating to the
Development (CCAD, Comisión Centroamericana de Ambiente
promotion of the development of the maritime and ports sub-sectors
y Desarrollo)
in Central America in order to strengthen, facilitate and foster internal
This agreement was signed in Costa Rica in December 1989 by
and external foreign commerce in the region. The member countries to
the Presidents of Costa Rica, El Salvador, Guatemala, Honduras and
the Commission are: Guatemala, El Salvador, Honduras, Nicaragua, Costa
Nicaragua. The objective of this agreement was to establish a regional
Rica and Panama. Colombia and Mexico are not part of COCATRAM.
regime of cooperation in order to achieve the optimal use of natural
resources, the control of pollution and restoration of an ecological
Current activities undertaken by NEP:
equilibrium which guarantees a better quality of life for the population
A regional diagnostic study on land-based sources of pollution in
of the Central American Isthmus. The Commission was mandated to:
the Northeast Pacifi c;
Valuate and protect the natural heredity of the region, characterised
A regional profi le on oil marine pollution and the capacity of the
by its high biodiversity;
Northeast Pacifi c countries against oil pollution;
Improve collaboration among member countries in order to
A regional coastal and marine environmental institution directory;
promote sustainable development;
and
Promote the coordination of governmental, non-governmental and
Several proposed technical and economic projects on specifi c
international institutions in order to optimally use local resources,
priority topics selected by the governments.
control pollution and restore an ecological equilibrium;
Manage fi nancial resources;
Central American Integration System (SICA, Sistema de
Strengthen national capacities related to natural resources and
Integración Centroamericana)
environmental management;
SICA was established by Belize, Costa Rica, El Salvador, Guatemala,
Harmonise political and legislative guidelines with strategies for
Honduras, Nicaragua, and Panama through the adoption of the
achieving sustainable development in the region; and
Protocol Letter of the Central American States Organization (ODECA),
Determine priority areas of action including, among others,
also known as the Tegucigalpa Protocol. This mechanism aims to initiate
education and environmental training, the protection of river
regional integration in order to promote peace, liberty, democracy and
basins and shared ecosystems, the management of tropical
development, based on respect, mutual support and promotion of
forest, pollution control, the importing and handling of harmful
human rights. The General Secretariat rotates every six months among
substances, and other aspects with potential risks for human
member states and supports regional integration initiatives.
health.
REGIONAL DEFINITION
25
Assessment
Table 5
Scoring table for the Central Equatorial Pacifi c sub-system.
This section presents the results of the assessment of the impacts
Assessment of GIWA concerns and issues according to
The arrow indicates the likely
of each of the fi ve predefi ned GIWA concerns i.e. Freshwater
scoring criteria (see Methodology chapter)
direction of future changes.
T
T
shortage, Pollution, Habitat and community modifi cation,
C
C
Increased impact
A 0
No known impacts
A 2
Moderate impacts
IMP
IMP
T
T
No changes
C
C
Unsustainable exploitation of fi sh and other living resources,
A 1
Slight impacts
A 3
Severe impacts
IMP
IMP
Decreased impact
Global change, and their constituent issues and the priorities
ts
ts
Central Equatorial
identifi ed during this process. The evaluation of severity of each
core**
ts
ts
Pacific sub-system
issue adheres to a set of predefi ned criteria as provided in the
vironmental
ther community
v
erall S
chapter describing the GIWA methodology. In this section, the
En
impac
E
c
onomic impac
Health impac
O
impac
O
Priority***
Freshwater shortage
2*
3
2
2
2.2
1
scoring of GIWA concerns and issues is presented in Table 5.
Modification of stream flow
2
Pollution of existing supplies
2
Because of the lack of signifi cant transboundary issues in the Southwest
Changes in the water table
2
Mexico and Pacifi c Colombian sub-systems, detailed Assessment and
Pollution
2*
2
2
2
2.2
2
Causal chain analysis focuses mainly on the Central Equatorial Pacifi c
Microbiological pollution
1
Eutrophication
2
sub-system. In the Southwest Mexico sub-system there was a lack of
Chemical
1
information on the only transboundary river, the Suchiate, and in the
Suspended solids
2
Pacifi c Colombian sub-system there are no transboundary rivers. The
Solid wastes
2
Thermal
0
regional experts therefore included analysis of national aquatic concerns
Radionuclides
0
which are believed to be aff ecting the pacifi c coastal zone of Mexico and
Spills
2
Colombia and their neighbouring countries. Only freshwater shortage and
Habitat and community modification
2*
2
0
2
1.6
5
pollution were assessed for the Southwest Mexico sub-system.
Loss of ecosystems
2
Modification of ecosystems
2
Unsustainable exploitation of fish
2*
2
0
2
1.6
4
During the assessment process it was evident that several environmental
Overexploitation
2
issues do not have quantitative indicators to allow them to be objectively
Excessive by-catch and discards
2
evaluated. They are therefore assessed using qualitative information and
Destructive fishing practices
2
Decreased viability of stock
0
may include a degree of subjectivity. The GIWA scoring table (Table 5)
Impact on biological and genetic diversity
0
shows the results for the Central Equatorial Pacifi c sub-system.
Global change
2*
2
2
0
1.9
3
Changes in hydrological cycle
2
Sea level change
1
Increased UV-B radiation
0
T
C
A
Changes in ocean CO source/sink function
0
Freshwater shortage
2
IMP
*
This value represents an average weighted score of the environmental issues associated to
the concern.
** This value represents the overall score including environmental, socio-economic and likely
The assessment of freshwater shortage evaluates the environmental and
future impacts.
*** Priority refers to the ranking of GIWA concerns.
socio-economic impacts of three transboundary issues: modifi cation of
26
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
stream fl ow, pollution of existing supplies, and changes in the water
have been caused by a progressive deterioration in the environmental
table. Freshwater shortage is more severe in the Southwest Mexico and
quality of the river basins due primarily to deforestation, increased
Central Equatorial Pacifi c sub-systems than in the Pacifi c Colombian
water extraction and pollution. River discharges are also aff ected by
sub-system.
dams, which interrupt the natural fl ow of nutrients to coastal waters, as
reported for the Bayano River in Panama by Franco (2001).
Modification of stream flow
Southwest Mexico
Discharges of the transboundary Lempa River measured at San Marcos
Although the sub-system's rivers are highly dynamic and characterised
in El Salvador show considerable inter-annual fl uctuations, although
by signifi cant inter-annual fl uctuations, discharges have shown a
only a short time series of data is available (Figure 13). According to
decreasing trend over the past 40 years, largely due to increasing
SNET (2002), the discharges of the Lempa River in 2002 were 42% below
abstraction for human uses. The mean annual discharge declined from
the historic average. The reduction in water availability has also been
323 m3/s to 278 m3/s between the periods 1965-1969 and 1975-1979,
attributed to the loss of fog forests in the upper sections of the basins,
and in the period 1979-1980 the mean discharge was only 177 m3/s, the
such as the Lempa (Llort & Montufart 2002).
lowest on record. The mean discharge had reduced by up to 45% by the
early 1980s. Figure 12 shows the discharges of the fi ve rivers with the
Deforestation and inappropriate agricultural practices in the
largest data series: Lerma-Santiago, Armería, Coahhuayana, Papagayo
catchments has aff ected run-off patterns and the fl ow rates of rivers
and Verde. These are not transboundary rivers but the changes in
such as the Choluteca, Lempa and Motagua. These human activities
discharges may have important implications for adjoining river basins
have increased erosion and consequently the amount of suspended
and coastal areas.
600
500
600
Lerma-Santiago R.
Armeria R.
400
500
(m /s)
Coahuayana R.
300
400
Papagayo R.
ges
(m³/s)
Verde R.
200
300
ges
Dischar 100
200
Dischar
0
100
1969 1970 1971 1972 1973 1974 1975 1976 1977 1978 1979 1980
0
Year
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
Figure 13 Annual discharges of Lempa River 1969-1974 and 1980.
Year
(Source: Vörösmarty et al. 1998)
Figure 12 Annual discharges of fi ve Mexican rivers.
(Source: Vörösmarty et al. 1998)
Drought events
Lake Chapala, the largest freshwater reservoir in Mexico, supplies water
Very high frequency
High frequency
to the city of Guadalajara. According to SEMARNAT (2004), fi ve years
Guatemala
Moderate frequency
after the Lake reached its maximum level in 1993, its water volume had
Honduras
decreased by 3 404 million m3, representing only 61% of its storage
capacity. This was attributed to increased consumption and higher
El Salvador
evaporation rates.
Nicaragua
Central Equatorial Pacifi c
Despite all countries of the Central Equatorial Pacifi c sub-system
having abundant water resources and extracting relatively limited
0
500 Kilometres
quantities (2.4% of the total availability, estimated at 690 km3), some
© GIWA 2005
areas experience water scarcity during the dry season when river fl ows
Figure 14 The Central American drought corridor. Colours show
are considerably reduced. This situation is exacerbated during warm
the frequency of dry periods.
El Niño events. Lower fl ows and reduced water availability and quality
(Sources: WFP/FAO 2002)
ASSESSMENT
27
solids in the river waters. The capacities of freshwater bodies, including
Pollution of existing supplies
reservoirs, in the lower sections of the river basins have been reduced
Southwest Mexico
due to sediment trapping. This is increasing the extents and frequencies
Only 23% of municipal wastewater (46 m3/s) receives treatment in
of fl oods. In Honduras, Costa Rica and Panama fl oods are now the most
the 1 018 treatment plants in Mexico (CAN 2002). Most wastewater is
frequent natural disaster.
therefore discharged into rivers, lakes and other water bodies without
treatment, thus reducing the availability of water suitable for human
El Niño events aff ect water availability in the sub-system by increasing
consumption.
the lengths of dry periods. Rainfall can be reduced by 30-60% in the
most aff ected areas (WFP/FAO 2002). During an El Niño, river fl ows are
Mexican authorities use an Index of Water Quality (ICA) to assess water
reduced signifi cantly, exacerbating the eff ects of a normal dry season
bodies. According to this index, the country's water bodies are classifi ed
(WFP/FAO 2002) (Figure 14).
as follows: 5% are excellent, 22% acceptable, 49% slightly polluted, 15%
polluted, 7% highly polluted and 2% contain toxic substances (CAN,
Pacifi c Colombian
2002). Two of the four basins with the highest pollution levels, Lerma
Although there are no transboundary rivers in the Pacifi c Colombian
(including Lake Chapala) and Balsas, are in the Southwest Mexico sub-
sub-system, the main rivers discharge considerable quantities of
system. Tables 6, 7 and 8 show various indicators of the quality of the
water into coastal areas with potential transboundary implications for
Lerma and Balsas rivers and Lake Chapala between 1990 and 2001.
neighbouring countries.
There appears to be no improvement in the general condition of these
water bodies. High concentrations of the measured parameters, such as
The assessment of stream fl ow modifi cation was based on available
biological oxygen demand (BOD) and chemical oxygen demand (COD),
information on the discharges of three major rivers, the San Juan, Patía
are maintained throughout the decade.
and Mira, and several minor rivers, as well as the average number of
rainy days on the Pacifi c slope (CCO 2002). There is no evidence of
Central Equatorial Pacifi c
signifi cant changes to the discharges of these rivers or the number of
Pollution is evident in several major basins of Central America, including
rainy days (Figures 15 and 16) (IDEAM 2001).
the Lempa River, shared by El Salvador, Guatemala and Honduras,
and the Grande de Tárcoles River basin in Costa Rica. El Salvador is
4 500
particularly aff ected as its main sources of freshwater, the Lempa River
Maximum
Average
4 000
Minimum
Trend
and Ilopango and Coatepeque lakes, are highly polluted by wastewater
3 500
discharges. A two-year study in the Lempa River showed that 95% of
3 000
(m³/s) 2 500
samples contained E. coli (Levin 2002). In 2001, a study undertaken in
ges 2 000
the rural areas of El Salvador found that 43% of the samples taken from
1 000
water supplied through pipes and 85% of the samples from wells were
Dischar 1 000
500
polluted by faecal coliforms (OPS/OMS 2003). In 2000, approximately
0
22% of the sub-system's population had no access to safe freshwater.
1965
1967
1969
1971
1973
1975
1977
1979
1981
1983
1985
1987
1989
1991
1993
1995
1997
1999
The level of coverage for rural populations is less; around 50% are
Year
without access to safe drinking water due to pollution and the lack of
Figure 15 Annual discharges of the San Juan River.
(Source: IDEAM 2001)
treatment facilities (OPS/OMS 2001a).
Maximum
Trend
1 200
Minimum
Average
According to PNUMA (2001), 95% of the municipal wastewater
1 000
generated in the sub-system enters natural water bodies without
800
(m³/s)
receiving appropriate treatment. In four of the six countries of the sub-
600
ges
400
system, only 1-4% of the wastewater disposed of through sewerage
Dischar
200
systems receives treatment, and in Nicaragua and Panama, 34% and
0
18% respectively (OPS/OMS 2001a). In Costa Rica, all wastewater
1965
1967
1969
1971
1973
1975
1977
1979
1981
1983
1985
1987
1989
1991
1993
1995
1997
1999
2001
transported through the sewerage system is discharged without
Year
treatment (Ballesteros 2003). Similarly in Honduras, wastewater
Figure 16 Annual discharges of the Patia River.
(Source: IDEAM 2001)
generated at Tegucigalpa, including that of industrial origin, is
28
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Table 6
Quality of the Lerma River according to physical, chemical and biological parameters 1990-2001.
Parameter
Unit
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
Ammonium(NH)
Mg/L
0.39
0.59
1.3
3.34
1.35
18.45
0.75
BOD (20°C, 5d)
MPN/100mL
13.5
2.9
15.3
16.1
9.58
17
12
92.33
11
30
7.31
COD (KCrO)
mgO/L
35
63.3
63.3
39
134
58
63.5
44.4
Nitrates (NO)
mgO/L
0.44
0.55
1.17
1.7
0.49
0.78
0.3
0.82
0.26
0.55
1.27
Ortophosphates
mg/L
0.39
0.55
1.65
2.6
5.63
2.83
2.83
1.01
Dissolved Oxygen
mgO/L
2.4
4.35
3.17
3.97
5.7
5.76
3.52
0.7
6.6
2.21
6.04
Dissolved solids
mg/L
223
487
782
634
7
500
418
Suspended solids
mg/L
304
380
40.3
189
253
8.22
40
63.6
pH
pH units
7.8
8
8
7.2
7.4
7.7
7.6
8
8.1
8.2
7.5
7.7
(Source: CAN 2002)
Table 7
Quality of the Balsas River according to physical, chemical and biological parameters 1990-2001.
Parameter
Unit
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
Ammonium(NH)
Mg/L
0.2
BOD (20°C, 5d)
MPN/100mL
1.74
1.
3.4
1.46
1.47
2.34
2.43
1.7
3.68
2.29
COD (KCrO)
mgO/L
10.4
5.1
25.8
10.4
43.5
16
Nitrates (NO)
mgO/L
0.11
Ortophosphates
mg/L
0.064
0.067
0.06
0.065
0.11
Dissolved Oxygen
mgO/L
6.38
6.26
7
5.97
3.7
5.2
3.26
6.43
6.69
6.66
2.9
6.06
Dissolved solids
mg/L
128
74
174
233
170
182
177
235
40.8
2.76
148
Suspended solids
mg/L
48
7.8
37.3
19
21
77.5
59
22.5
pH
pH units
8.4
7.7
7.9
8
7.5
7.4
7.3
(Source: CAN 2002)
Table 8
Quality of the Chapala Lake according to physical, chemical and biological parameters 1990-2001.
Parameter
Unit
1990
1991
1992
1994
1996
1997
1998
1999
2000
2001
Ammonium(NH)
Mg/L
0.41
0.32
0.33
1.79
0.13
0.22
0.15
0.238
1.26
BOD (20°C, 5d)
MPN/100mL
1.71
1.23
1.22
1.17
2.34
2.85
2.46
3.86
2
3.59
COD (KCrO)
mgO/L
30
31.61
41.29
31.1
39.6
42.4
47
58.43
Nitrates (NO)
mgO/L
0.15
0.36
0.18
0.23
0.17
0.12
0.12
0.082
0.195
Ortophosphates
mg/L
0.24
0.28
0.27
0.32
0.43
0.38
0.38
0.382
0.46
0.751
Dissolved Oxygen
mgO/L
7.6
7.18
7.45
6.8
6.7
7.3
7.55
7.34
8.6
8.1
Dissolved solids
mg/L
662
850
613
481.7
613.5
643.5
730.8
790
802
943
Suspended solids
mg/L
52
40
37
35.7
25
44
61.6
66
66
89
pH
pH units
8.92
8.59
7.59
8.55
8.80
9
9.2
8.75
(Source: CAN 2002)
discharged into Choluteca River without treatment. In Guatemala, only
Today, approximately 45% of the pollution charge and BOD reaching
15 out of 344 municipalities apply any treatment to their wastewaters
the Tárcoles River originates from the coff ee industry. Some studies
from urban areas. Thus, most of the pollution in the surface waters of
have shown that this industry may be responsible for up to 77% of the
the sub-system originates in the lack of appropriate treatment.
pollutant load (Ballesteros 2003).
Some coastal industries use large amounts of water which is later
Higher water demand, driven largely by the expansion of the tourism
discharged into the surrounding water bodies without treatment. In
industry, has led to increased abstraction from aquifers, which are a
Costa Rica, the coff ee industry is still a major source of pollution, despite
major source of water for coastal communities. This has led to saline
a programme to reduce pollutant discharges being established in 1989.
intrusion in aquifers used by 31% of fi ve communities monitored,
ASSESSMENT
29
some of whom were forced to abandon their source (Gamez 2002).
that year was 424 000 m3/day but it reached 553 000 m3/day by 2000
Aquifers in the metropolitan area of Alajuela, Cartago and Guanacaste
(MARENA 2003). In the dry arc of Azuero (Panama), aquifers are pumped
have increasing concentrations of nitrates originating from fertilisers
to their limits during drought periods. In Honduras, the renewable
and septic tanks (Reynolds & Fraile 2002). Urban and agricultural run-
volume of groundwater in the Pacifi c slope was estimated to be 1.1 km3/
off are responsible for polluting the Managua aquifer that provides
year. A reduction in this volume has been reported in the valleys of
freshwater to 1.2 million people. Around 20% of the freshwater used
Choluteca, Tegucigalpa and Comayagua due to extensive abstraction
by the population in the capitals of San José, San Salvador, Managua
for irrigation (PNUMA 2001). In Costa Rica, the aquifer that supplies the
and Tegucigalpa comes from underground sources, which are being
city of San Jose is depleted (Lezama-López 2003). Irrigated agriculture
aff ected by pollution.
withdraws enormous quantities of water in Costa Rica (Ballesteros 2003).
The Grande de Tarcoles River basin's natural forest cover has reduced
The sub-system has one of the largest rates of pesticide consumption in
from 66 096 ha in 1992 to 38 384 ha in 2000; this may aff ect both the
Latin America (2 kg/person), attributed to the intensifi cation of farming
recharge rate and the water quality of the aquifers (Ballesteros 2003).
to suply the export market. There is also evidence that agricultural by-
products make a signifi cant contribution to the deterioration of surface
According to the UNESCO International Hydrological Programme (IHP),
water quality. According to Ballesteros (2003), in Costa Rica around 50%
the total water abstracted in the sub-system increased by 2.1 km3
of all agricultural wastes enter water bodies.
between 1950 and 2000 and will increase to 2.9 km3 in 2010. Water
abstraction in 2010 will be nine times the rate of 1950, and rates are
Pacifi c Colombian
expected to increase by a further 21% by 2025. Illegal connections
Most available information regarding the pollution of freshwater
consume around 40% of the water available in the sub-system.
supplies is on urban centres (Calero et al. 1996). In Tumaco and
Buenaventura there is a risk of contamination due to the large volumes
Pacifi c Colombian
of hydrocarbons transported in the area. In the rest of the Colombian
No quantitative information was available concerning this issue
Pacifi c basin, hydrocarbon activities are less signifi cant and there
but water is known to be highly abundant in Colombia with high
is greater water exchange (Castro et al. 2003). Freshwater supplies
aquifer recharge rates. Changes in the water table were therefore not
can also be contaminated with persistent organic pollutants (POPs),
considered to have any adverse environmental impacts. Although there
particularly DDT, and by a variety of other agrochemicals used in illegal
is an inventory of the aquifers exploited in other parts of Colombia, it
drug cultivation (IDEAM 2002).
does not include the Pacifi c slope (IDEAM 2001).
Changes in the water table
Socio-economic impacts
Southwest Mexico
Southwest Mexico
In 2000, 96 of Mexico's 653 aquifers were considered overexploited
Water availability in Mexico has decreased from 31 000 m3/person/year
(SEMARNAT 2002). In recent years, the volume of water extracted has
in 1910 to 10 000 m3/person/year in 1970, and only 5 000 m3/person/
remained constant at about 29 km3/year. The aquifers in the Lerma-
year in 2001. There is expected to be only 3 750 m3/person/year by
Santiago-Pacifi co basin have been overabstracted mainly to supply
2020 (SEMARNAT 2002). Mexico consumes more than 15% of its water
water for agriculture. In the state of Nayarit, saline intrusion in the
resources annually, which is classifi ed as moderate pressure (PNUMA
aquifers has been reported (SEMARNAT 2002). Groundwater is used
2000). Water demand has increased in parallel with population growth
less, without any apparent problems, in the remaining basins of the
and economic development.
sub-system.
In 2000, Mexico had moderate sanitation coverage and freshwater
Central Equatorial Pacifi c
supply (76% and 88% respectively) (SEMARNAT 2002). Between 1990
Groundwater is the main source of freshwater in this sub-system.
and 2000, progress in improving the coverage of basic services was
In El Salvador, around 60% of the freshwater is sourced from the
variable amongst the states located in the Southwest Mexico sub-
aquifers of the metropolitan area of San Salvador, which are currently
system. On average, only 68 l/person/day of the water supply is
overabstracted. Groundwater abstraction in Nicaragua exceeds the
disinfected in Mexico which is posing health risks for a large proportion
recharge rate of aquifers. In 1995, the potential abstraction rate was
of the population, particularly in the southernmost states of the sub-
estimated at 535 300 m3/day for the Managua aquifer. The demand for
system which contain mainly rural populations.
30
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
The overexploitation of aquifers is also of concern given that 70% of the
The depletion and contamination of groundwater resources may
freshwater supply is groundwater; 75 million people (55 million in cities
impede economic development in the sub-system. If this trend
and 20 million in rural communities) obtain their water supply from
continues, it is expected that by 2025 the sub-system will be developing
aquifers (SEMARNAT 2002). In future, it will be diffi
cult to substantially
under conditions of increasing water shortage.
increase water supply coverage as there is already enormous pressure
on water resources in the Southwest Mexico sub-system.
Water availability per capita declined by 62% between the 1950s and
the 1990s. Between 1995 and 2025, water availability is expected to
Water confl icts have arisen in the past decade in Mexico. Sainz & Becera
decrease from 8 580 m3/person to 1 780 m3/person in El Salvador and
(2005) reviewed 3 800 cases of confl ict related to water between 1990
from 33 810 m3/person to 4 830 m3/person in Guatemala (PNUD 2003).
and 2002. Most of these confl icts were concerning availability, tariff
Agriculture will be one of the sectors most aff ected by water shortages
increases, infrastructure improvements or aquifer related issues.
because of the large amounts of water needed for export products.
About 60% of these cases occurred in locations where aquifers are
Extension of agricultural areas will further reduce water availability,
overabstracted.
particularly in El Salvador and Costa Rica (Pratt & Girot 1999). A large
proportion of the workforce is employed in the agricultural sector, thus
Central Equatorial Pacifi c
a decline in agricultural production due to decreased water availability
Although the availability of water per person is adequate, only 78% of
will increase unemployment. In drought prone areas, poverty will
the population had access to drinking water services in 2000. The
increase resulting in social instability. Tourism, another large consumer
Pan-American Health Organization classifi es the sub-system as level V
of water, would also suff er as a result of water shortages. Tourism
low-coverage level (OPS/OMS 2001a). The level of coverage has not
accounts for around 13% of the sub-system's gross product and the
increased at the same rate as population growth. In fact, the proportion
sector is expected to grow in the future (PNUMA 2001).
of the population without adequate sanitation and freshwater services
increases year by year. Poor water quality is posing health risks for the
In the drought corridor, limited water availability and food insecurity
population. In some rural areas where freshwater services are often
have forced people to gather food from the forest. Over 20% obtain
interrupted by technical failures there is higher prevalence of water-
water from public or private wells. Small farmers do not own the land
related diseases, especially diarrhoea.
and pay for its use with part of their harvest, but during dry years, when
harvests are reduced or lost, they struggle to pay the land owners. In
The contamination of several freshwater sources in the Central
the drought corridor the eff ects of reduced rainfall during the El Niño
Equatorial sub-system has increased the cost of treatment for drinking
become most evident during the sowing and harvest seasons (May-
water. Pollutant concentrations in water bodies increase when river
August and September-November), aff ecting around 8.6 million people
fl ows decrease during dry periods, increasing the risk of pathogenic
(WFP/FAO 2002).
diseases and the rates of morbidity and mortality. Acute diarrhoea is
the main cause of infant mortality (children under fi ve years old). In
Pacifi c Colombian
El Salvador, 12 000 children die annually due to water-borne diseases
The most aff ected economic sectors include agriculture, industry and
and annual cases of diarrhoea and parasitism increased from 150 000 to
public services (energy and water supply). The sectors demanding the
220 000 over a 10-year period (Levin 2002).
highest volumes of water are agriculture (48%), domestic use (36%)
and industry (7%) (MMA 2002c). The economic implications of water
The Pan-American Health Organization has demonstrated that access
shortages include (i) increased costs of extraction and (ii) increased
to water is directly related to poverty (OPS/OMS 2001b, 2001c), which
costs of water treatment and pollution control. In the Valle del Cauca
is more severe in rural areas. The Indian population, artisanal fi shermen
Department, for example, signifi cant investment has been required to
and small farmers have particularly limited access to safe water and are
supply water to the agricultural sector. Water charges and retributive
vulnerable to water-borne diseases. In rural areas in El Salvador, 40% of
rates have been introduced in many areas to control water pollution
the population (around 200 000 people in 1999) use water from natural
(MMA 2002d).
sources. Poverty has increased as a result of water shortages, combined
with unemployment and reductions in food availability. The resultant
According to DANE (2001), despite abundant water supplies on the
social insecurity has prompted migration from rural areas to cities.
coast of Colombia, technical and fi nancial constraints as well as poor
management are responsible for the low level of freshwater supply
ASSESSMENT
31
coverage, which has negatively impacted human health and the
the lack and poor quality of freshwater supplies. Rural populations are
population's quality of life. The low level of coverage in rural areas is
particularly aff ected as there are limited water and sanitation services
resulting in high rates of infant mortality and morbidity, the prevalence
and most water is obtained directly from natural sources.
of gastroenteric diseases and the steady increase in cases of cholera
(INDERENA 1992). The infant mortality rate is three times higher than
the national average (IIAP 2001a). In 1997, the survey Life Quality by the
T
C
A
National Department of Statistics (DANE) indicated that water coverage
Pollution
IMP
was less than 70% in the Pacifi c region, with 17% of the population
supplied by communal aqueducts, 4% wells, 1% rainwater, 7% rivers
Pollution may become critical if mitigation measures are not
and 1% by other sources.
implemented in the short-term. Human activities are resulting in
pollution entering the aquatic environment, particularly municipal
The sanitation situation in the coastal municipalities is precarious in both
wastewater, hydrocarbon spills and agricultural run-off . Although tides,
coverage and quality. Freshwater supply and sanitation coverage in the
currents and water exchange can disperse the organic matter contained
largest villages is, at most, 48% and 10%, respectively. In Buenaventura
in coastal water bodies, population growth and economic development
and Tumaco, the major coastal cities in the sub-system, freshwater
is leading to increasing pollution loads which are resulting in adverse
coverage is 35% and sanitation 7%, whereas in the highland cities
impacts on the marine environment. No sources of thermal pollution
(outside of the sub-system) of Bogota, Medellin and Cali, freshwater
were reported in the region and is therefore not further discussed.
coverage is 85%, 91% and 94%, respectively. Freshwater coverage in
rural areas is only 4% and sanitation is less than 1% (IIAP 2001a).
Microbiological
Southwest Mexico
Conclusions and future outlook
Mexico is the major polluter in the GIWA Eastern Equatorial Pacifi c
Water resources are abundant but unevenly distributed in the
region, responsible for two-thirds of the region's total wastewater
region. There are areas with abundant water resources and others
discharged into the Pacifi c Ocean (1.17 billion m3/year) (PNUMA
that suff er from shortages during the dry season. Areas defi cient
2001). In 1999, the total volume of wastewater discharged by Mexico
of water are generally the more densely populated and have the
was 780 150 m3, with a BOD load of 226 660 tonnes and COD load of
greatest concentration of economic activities. Aquifers are particularly
508 180 tonnes. Further, the projected population by 2020 will generate
overexploited. During extreme seasons, some areas of the region can
a volume of wastewater twice that of 1990.
experience catastrophic droughts, or fl oods associated with hurricanes
that track across the Caribbean. The situation is exacerbated by
The enormous amount of untreated wastewater entering the aquatic
inappropriate natural resource management practices, especially
environment is deteriorating the environmental quality of the water
deforestation that aff ects erosion and run-off patterns in most river
bodies in the sub-system. According to PNUMA (2001), domestic
basins.
wastewater is the primary land-based source of pollution in the coastal
marine environment. Table 9 shows values of faecal coliforms reported
Population growth and economic development, such as agriculture,
in several major water bodies in the sub-system. Faecal coliforms in
industry and tourism, will increase the future demand for water, thus
the Lerma and Balsas rivers have values that continue to exceed the
increasing the extent and severity of water shortages. Groundwater
levels permissible in Mexico (<10 000 MPN/l for water supply sources).
abstraction is threatening aquifers and resulting in acute water shortages
In contrast, conditions in Lake Chapala improved considerably during
in several areas whose populations are dependent on groundwater.
the second half of the 1990s.
The use of groundwater will increase as the quality of surface water
Table 9
Total coliform (MPN/100mL) in major water bodies of
deteriorates due to population growth, deforestation, increasing food
the sub-system during the period 1991-2001.
agriculture and longer drought periods. Freshwater supply coverage
Water body
1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001
is particularly low in rural and minor urban settlements. The lack of
wastewater treatment and the associated contamination of freshwater
Lerma River
2,000 4,700 2,800 4.3E4
1.3E4 6.8E4 1.4E6 1,000 4,017 4,076
systems are reducing the availability of water for direct consumption,
Balsas River
1.8E4 1.5E4 9.8E4 1.2E6 5,008 500
3.6E4 6,133
thus increasing water treatment costs. Human health impacts such as
Lake Chapala 4.4E5 5.3E7
18.5
48
24
26
46.8
5
4,625
increased infant mortality and morbidity have been associated with
(Source: CNA 2002)
32
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Microbiological pollution on Mexican beaches has been identifi ed
Signifi cant discharges are introduced through the basins of the rivers
as a priority issue by Mexican authorities due to the potential eff ects
Tárcoles, Tempisque and Barranca into the Gulf of Nicoya, Costa Rica
on human health and tourism. In 2002, the Ministries of Environment
(León in Ramírez & Espejel 2001). If the current population growth
and Natural Resources (SEMARNAT), Health (SS) and the Navy (SEMAR)
continues and the volumes of untreated discharges per head of
began conducting microbiological monitoring on beaches. This
population are maintained, the total volume of discharges will double
study showed that the most important tourist beaches located in the
in the next two decades. These discharges are directly responsible for
Southwest Mexico sub-system, such as Zihuatanejo, Acapulco, Bahía de
the presence of pathogenic microorganisms, such as coliforms, on the
Banderas, Puerto Angel and Puerto Escondido, were among the most
beaches and in the coastal waters of Costa Rica, El Salvador, Nicaragua
polluted beaches in Mexico (SEMAR 2004).
and Panama. No information was available about the contribution
of livestock to the microbiological pollution of surface waters in the
A study carried out in Acapulco Bay over the period 1998-2000 shows
sub-system. However, its impact may be signifi cant considering the
that water quality decreases seasonally at the beginning of the rainy
importance of livestock production to the regional economy.
period in July due to increased run-off and tourism wastewater;
maximum values of between 100 000 and 10 million MPN/l are
High concentrations of pathogenic micro-organisms associated
recorded in July (Leal et al. 2000). During this study Vibrio cholerae and
with water pollution have been recorded in water bodies and on
Shigella sp. were detected in several locations.
beaches of the sub-system, posing health risks for the population and
aff ecting some economic activities. Concentrations of total coliforms
Central Equatorial Pacifi c
between 80 and 16 000 MPN/ml and faecal coliforms between
The main source of microbiological pollution is the discharge of
0 and 160 MPN/l were recorded in Panama Bay between 1985 and
untreated wastewater into the sewerage system or natural water
1987 (CPPS 2000). The highest values coincided with wastewater
bodies. The failure to appropriately dispose of excrement and the use
outfalls. In Puntarenas, Panama, concentrations of total coliforms
of latrines and septic wells in porous soils is contributing signifi cant
between 160 and 200 million MPN/l and faecal coliforms between
loads of microbiological pollution. The total volume of wastewater
20 and 92 million MPN/l were recently reported (Acuña et al. in Wo-
discharged into the sub-system was 367 billion m3 in 1999, with a BOD
Ching & Cordero 2001). All these concentrations exceed national and
load of 104 630 tonnes and a COD load of 234 350 tonnes (Table 10).
international standards (EPA 1983).
These total loads may be considered as minimum values and are likely
to represent only around 20-22% of the total wastes discharged in the
Several rivers including Torres, Maria Aguilar, Tiribi, Virilla, Segundo and
sub-system. The low levels of wastewater treatment in the sub-system
tributaries of Grande de Tárcoles River have concentrations of total
(10.3% on average) results in around 95% of wastewater reaching
coliforms above 100 million MPN/l and the surface aquifers of Barva
the Pacifi c Ocean with a high load of organic matter, nutrients and
are unsafe due to high concentrations of coliforms (Ballesteros 2003).
microbial pollutants (PNUMA 2001). Table 11 shows the main coastal
In El Salvador, several beaches and coastal areas, such as Jiquilisco, El
areas aff ected by pollution.
Zapote and Don Diego, have concentrations of coliforms above national
and international standards. In the El Zapote estuary (Barra de Santiago),
Table 10
Wastewater, solids and nutrient discharges in the
Raquena & Miton (in Rubio 1994) found concentrations of faecal
Central Equatorial Pacifi c sub-system by country.
coliforms between 600 and 5 000 MPN/l and, in Zanjones, La Danta and
BOD
COD
Suspended
TDS
N
P
Wastewater
Country
(tonnes/
(tonnes/
solids
(tonnes/
(tonnes/ (tonnes/
Aguachapio, concentrations of between 3 000 and 240 000 MPN/l, and
(10³m³/year)
year)
year) (tonnes/year)
year)
year)
year)
total coliforms of around 240 000 MPN/l.
Panama
166 010.8
45 898.1
102 644.7
48 600.4
82 192.5
7 431.1
900.7
Costa Rica
30 366.1
8 257.9
18 451.6
8 499.0
15 136.2
1 368.50
165.9
During the 1990s around 60% of the sub-system's urban population
was connected to the sewerage network and 51% used some type
Nicaragua
45 501.0
14 275.7
32 123.3
18 136.0
21 272.3
1 923.20
233.1
of in situ service. In contrast, the rural population was not served by a
El Salvador
49 589.8
14 353.8
32 175.3
16 344.6
24 075.8
2 176.70
263.8
sewerage network and all sanitation solutions were in situ. By the end
Honduras
59 888.1
17 030.3
38 141.1
18 874.7
29 300.9
2 649.10
321.1
of the 1990s the sanitation coverage improved considerably, especially
Guatemala
15 964.0
4 814.2
10 812.9
5 810.9
7 607.3
687.8
83.4
in Nicaragua and Guatemala, where it had increased up to 80% by
Total
367 198.8
104 630.0
234 348.9
116 265.6
179 585
16 236.4
1968
2000. During the same period, El Salvador and Honduras increased
(Source: PNUMA 2001)
their level of coverage by only 8% (OPS/OMS 2001a), and Panama from
ASSESSMENT
33
Table 11
Coastal areas aff ected by pollution in the Central Equatorial Pacifi c sub-system.
Country
Severe
Severe/Moderate
Moderate
Slight
Grande de Tarcoles Barranca Basin
Puntarenas Estuary
Moín
Golfito
Gulf of Nicoya
Wastewater, Solid wastes, Sedimentation, Habitat
Limón
Agua Dulce
Costa Rica
Wastewater, Solid wastes, Sedimentation,
modification
Puerto Caldera
Agrochemical
Wastewater, Agrochemicals, Oil
Estero Jaltepeque
Bahía Jiquilisco
Lempa River basin, Sampuyo, Jalponga etc.
Bahía La Unión
El Salvador
Wastewater, Solid wastes, Sedimentation,
Acajutla
Agrochemical, Heavy metals
Agrochemical, Heavy metals Wastewater, Oil
Puerto Quetzal
Champerico
Guatemala
Wastewater
Oils, Solid wastes
Gulf of Fonseca
Amapala
Agrochemicals, Nutrients, Aquaculture wastes
Cedeño
Honduras
San Lorenzo
Wastewater, Solid wastes, Oil
Real Estuary
Corinto
Central zone, rivers
Volcano-Pacific basin
Atoya-Sucio River (El Viejo-Chinandega- North Pacific)
Jesús-Quizada
Negro River
Chiquito River (Leon-South Pacific)
Wastewater, Nutrients, Solid wastes
Nicaragua
Wastewater, Solid wastes, Pesticides,
Jesús Quisala River (San Rafael, Managua-South Pacific)
Sedimentation, Deforestation
Grande Carazo River (Jinotepe, Carazo-South Pacific)
Wastewater, Solid wastes, Pesticides, Sedimentation,
Nutrients
Panama Bay (inner area)
Vacamonte
Gulf of Chiriqui
Agua Dulce
Panama
Wastewater, Solid wastes, Pesticides,
Solid wastes, Oil
Charco Azul
Nutrients, Oil
Eutrophication, Oil, Heavy metals
Sedimentation, Pesticides, Oil
(Source: PNUMA 2001)
84% to 93%. The situation of Costa Rica was diff erent; during the early
most of the monitored beaches located in the Nariño, Valle del Cauca
1990s the coverage was 97% but a decade later it had decreased to
and Choco Departments surpassed the Colombian Permissible Limit
94%. Despite this, Costa Rica continues to have the highest level of
(2 000 MPN/l), especially during the rainy season (Vélez et al. 2003).
sanitation coverage in the sub-system. According to OPS/OMS (2001a),
the treatment of industrial effl
uents is very low, 1-4% for most countries
Eutrophication
though 34% in Nicaragua.
Southwest Mexico
Wastewater discharges and agricultural run-off are the main sources
Pacifi c Colombian
of nutrient enrichment in the aquatic environment of the Southwest
A total of 87 200 m3/day of untreated wastewater is discharged into the
Mexico sub-system. Domestic discharges were estimated to introduce
coastal waters of the Colombian Pacifi c, with a biological degradable
a total of 34 200 tonnes of nitrogen and 4 150 tonnes of phosphorus
organic (BDO) charge equivalent to 16.5 tonnes/day (Garay et al.
every year into the Pacifi c Ocean (PNUMA 2001). The major source
2002). Most of this load (91.5%) is produced in the Valle del Cauca and
of nutrient enrichment in the coastal environment, however, is from
Nariño Departments, especially by the urban centres of Buenaventura
agricultural run-off . In Mexico, fertiliser application increased from
and Tumaco. Microbiological pollution has continued to exceed
2.87 million tonnes in 1980 to 3.93 million tonnes in 2000 and use per
permissible limits in the waters of both these cities. Table 12 shows
hectare increased over the same period from 110 kg/ha to 160 kg/ha
the concentrations of coliforms in the cities in the late 1980s. In 2002,
(Espinoza 2002). Contreras et al. (1995) analysed the water of 39 coastal
lagoons in Mexico, 20 of which are located in the Southwest Mexico
Table 12
Total and faecal coliforms at Tumaco and
sub-system. They concluded that most of these water bodies are in
Buenaventura.
a permanent state of eutrophication. Some lagoons contained high
Tumaco
Buenaventura
Total coliforms
Faecal coliforms
Total coliforms
Faecal coliforms
concentrations of nitrites and nitrates, whereas others in the states
Year
(MPN/100 mL)
(MPN/100 mL)
(MPN/100 mL)
(MPN/100 mL)
of Oaxaca and Chiapas showed high concentrations of phosphorus.
Min
Max
Min
Max
Min
Max
Min
Max
In Lake Chapala, high levels of phosphorus (80 times higher than
1986
91
11 000
36
11 000
40
11 000
200
4 600
1987
36
11 000
18
11 000
44
15 000
21
2 300
permitted by international standards) and the proliferation of algae
1988
17
43 000
20
3 300
210
110 000
93
46 000
and invasive aquatic weeds were clear indicators of eutrophication
1989
12
90 000
22
27 000
13
4 600
13
4 600
(Living Lakes 2005).
1990
33
66 000
19
22 000
80
9 200
79
5 400
(Source: CPPS 2000)
34
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Central Equatorial Pacifi c
Chemical
Nitrates and phosphates contained in municipal wastewater and
Southwest Mexico
agricultural run-off are responsible for eutrophication in the rivers and
Mexico uses more pesticides than any other country in the GIWA
coastal areas of the sub-system. Farmers in the sub-system use large
Eastern Equatorial Pacifi c region. Between 1974-1977 and 1982-1984,
quantities of fertiliser, with consumption having increased from 76 kg/
average annual pesticide use increased by 44%, from 19 148 tonnes to
ha in 1990 to 131 kg/ha in 2000. Deforestation exacerbates the problem
27 630 tonnes per year. DDT has been regularly used in Mexico since
by causing soils enriched with nitrogen to be washed out.
the 1950s to combat malaria. Around 70 million tonnes of DDT has
been used in the country but the number of doses applied per year
Agriculture, livestock and wastewater run-off pollutes the Grande
has decreased considerably from 5.7 million in the period 1957-1960 to
de Tarcoles River basin and severely aff ects the waters of the Gulf of
829 000 in the 1980's (ISAT 2001). Residuals of DDT have been found in
Nicoya and the mid-Pacifi c coast. The basin contributes 61% of the
humans (maternal milk, fatty tissue and blood, 0.9-17 mg/kg), soil (50-
nitrogen and 31% of the phosphorus that is discharged into the Gulf
83 mg/kg), sediments (1.8-27 µg/kg), food (milk 85-159 µg/kg and butter
(Díaz & Fernández 1994). In total, the Gulf receives 300 tonnes/year of
49 µg/kg), cattle (0.21-1.9 mg/kg) and in aquatic species such as shrimp
phosphorous and 2 000 tonnes/year of nitrogen from the Grande de
and oysters (0.056-9.2 ng/g) and fi sh (38 ng/g) (ISAT 2001).
Tárcoles and Barranca river basins (Table 13) (León in Ramírez & Espejel
2001). In Panama Bay, at the outlets of the rivers Curundú, Matías
Heavy metal contamination is particularly high in the Lerma River basin.
Hernández, Juan Díaz, Matasnillo, Abajo and Tapia, there are high
It is estimated that petrochemical, metallurgic, textile and automotive
values of nitrates, phosphates and chlorophyll-a. These rivers receive
industries located in the central states of Queretaro and Guanajuato
wastewater from Panama City (Álvarez et al. 1989). High nutrient
discharge more than 12 400 g of chromium and more than 4 300 g of
concentrations have also been reported at Puerto Corinto, El Realejo,
zinc daily into the waters of the basin (SEMARNAT 2004). The Chapala
Estero Chocolate, La Esparta and El Real in Nicaragua (Sánchez 2001).
Lake is highly polluted with heavy metals (e.g. cyanide, chromium, leads
The total charges of nitrogen and phosphorus from coastal settlements
and mercury), causing toxicological induced mutations in some fi sh
are around 16 270 tonnes/year and 1 970 tonnes/year, respectively.
species (Living Lakes 2005). Concentrations of heavy metals in most
Mexican water bodies, sediments and organisms (molluscs, crustaceans,
Harmful Algal Blooms (HABs) produced by algae of the genus Anabaena
fi sh and mammals) are relatively low, although moderate concentrations
and Oscillatoria have been associated with eutrophication processes in
have been found in parts of the northeast Pacifi c (Páez 1999).
Jiquilisco Bay and at Puerto Triunfo in El Salvador (Rubio et al. 2001).
Central Equatorial Pacifi c
Table 13
Concentrations of nutrients in the Gulf of Nicoya.
Agricultural run-off is the main source of chemical pollution, caused
Site
Omg/l
Si(OH)uM
POuM
NO-NOuM
Secchi (m)
by the widespread use of pesticides in agriculture, especially for
Gulf upper part
5.3-8.6
5.7-14.3
0.15-2.64
0.2-25.7
0.2-1.6
Gulf lower part
7.5-8.7
1.7-35.9
0.04-0.81
0.0-12.6
1.9-17.6
export production. Pesticide application (2 kg/person) is one of the
Tarcoles River
5.8
17.3
3.20
16.80
-
highest in Latin America (Tribunal Centroamericano del Agua 2004).
Barranca River
6.7
128.0
0.71
12.0
-
Large amounts are used in the production of export crops such as
Tempisque River
5.4
13.3
0.71
14.6
-
rice, bananas and sugar cane. According to Álvarez & Manelia (1996),
(Source: Wo-Ching and Cordero 2001)
polychlorinated biphenyls (PCBs), mirex, lindano and heptacloro
are discharged by the Bayano River into Panama Bay. In El Salvador,
Pacifi c Colombian
the Jaltepeque estuary and Jiquilisco Bay receive waters heavily
Besides the nutrients contained in wastewater, agricultural run-off
contaminated with pesticides from the rivers Lempa, Grande de
is contributing to the nutrient enrichment of the coastal marine
San Miguel, Sapuyo, Jalponga, Huiscoyolapa, Amayo, Requinte and
environment. Colombia has the highest rate of fertiliser consumption
El Molino (Rubio et al. 2001). In Costa Rica, rivers carrying pesticides
(81 kg/ha) on the Pacifi c coast of South America (CPPS 2000). The total
to the Gulf of Nicoya include Tempisque, Grande de Tárcoles and
consumption of fertilisers in Colombia reached 556 000 tonnes in 1997.
Barranca (Wo-Ching & Cordero 2001, León in Ramírez & Espejel 2001).
Some areas, such as water bodies near Tumaco and Buenaventura, have
An estimated 250 000 m3 of liquid residuals are deposited daily in the
eutrophic conditions (Escobar 2001).
Virilla River (Grande de Tárcoles upper basin) which take only 24 hours
to reach the Gulf of Nicoya (León in Ramírez & Espejel 2001).
ASSESSMENT
35
High concentrations of pesticides have been found in coastal waters,
Heavy metals such as lead, copper and chromium have been reported
sediments and biota, posing risks for humans and other living
in sediments and surface waters in several countries in the sub-system,
organisms. Cedeño (1995) reported DDT concentrations of 12 ng/g in
notably Panama, Nicaragua and Costa Rica (Table 16). Concentrations
surface sediments, 5 200 ng/g in the tissue of clams at Peñitas-El Toro
of <1.0 ppb of mercury and 4-38 mg/l of copper were found in
(Nicaragua) and 450 ng/g in the tissue of black clams (Anadara spp.) in
Panama. These mercury concentrations are not signifi cant (EPA 2005),
the El Realejo estuary. Pesticides in fi sh, crustacean and mollusc tissue
but those of copper exceed national standards and pose a risk to
were reported at Jiquilisco Bay, El Salvador (Rubio et al. 2001), and
aquatic organisms. High levels of cadmium and copper have been
Panama Bay (Alvarez et al. 1989, Alvarez & Manelia 1996) (Tables 14 and
found in three areas of Nicaragua: El Sitio, Pasacaballos and Puerto
15). The concentrations of DDTs in black clams indicate high pollution
Corinto (Cedeño 1995, Sánchez 2001). Totals of 400 tonnes of copper,
levels and those in surface sediments exceed international standards
130 tonnes of nickel, 86 tonnes of lead, 600 tonnes of zinc and 75 tonnes
(FDA 1993).
of chromium are discharged annually into the Gulf of Nicoya, Costa Rica
(León in Ramírez & Espejel 2001).
Heavy metals from mining washes and industries, which are introduced
Table 16
Concentrations of heavy metals found in sediments in
directly into natural water bodies of the sub-system, are also present
several areas of the Central Equatorial Pacifi c sub-system.
at these sites. Mining activity is artisanal and carried out far away
Lead (ug/g)
Copper (ug/g)
Chromium (ug/g)
from coastal areas; run-off from these activities enters surface waters.
Country/site
1981-1996
1985
1998
1986
1981-1996
1998
Examples include discharges of cyanide and mercury from gold
Panama
extraction (PNUMA 2001). Six mining accidents occurred in Panama
Panama Bay
20-204
27-110 000
between 1995 and 2000 causing cyanide spills. In Nicaragua, around
Costa Rica
124 kg of mercury is released annually from artisanal mining with
Gulf of Nicoya
5.4-83.6
0.13
862.7
unknown eff ects on coastal waters.
Nicaragua
Table 14
Concentrations of pesticides in the tissue of several
El Sitio
13.87
2.42
10.96
species in Jiquilisco Bay, El Salvador.
Pasacaballo
13.96
2.73
12.52
Common/scientific name
DDT
Endrin
Dieldrin
Etil Parathion
Corinto
16.9
3.13
11.73
Bass (Cynoscion sp)
2.33
0.16
0.04
0.00
(Source: Alvarez et al. 1989, Sánchez 2001, Wo-Ching & Cordero 2001)
Mullet (Mugil ssp)
1.86
0.27
0.05
0.00
Industrial discharges of chemical substances are poorly documented
Grunt (Pomadasys sp)
1.79
0.07
0.52
0.00
in the region. Most available information is related to the presence of
Shrimp (Penaeus sp)
0.65
0.00
0.00
0.00
inorganic chemicals in organic matter. This was discussed in the section
Black clam (Anadara sp)
0.75
0.05
0.03
0.00
on microbiological pollution. Other chemicals are discharged in small
Mussela (Mytella sp)
0.62
0.03
0.02
0.01
proportions within wastewater.
Starfish (Oreaste sp)
0.35
0.06
0.02
0.00
(Source: Cedeño 1995)
Pacifi c Colombian
Table 15
Concentrations of pesticides found in some marine
Around 33 000 tonnes/year of 600 diff erent pesticides are used in
species in Panama Bay.
Colombia, including organophosphate, organochloride, carbonates
Common/scientific name
Pesticide
Concentration (ppb)
and piretrins (Garay et al. 2001). They are used mainly in rice and potato
Pompano (Vomer declivifrons)
PDC-1260
0.62
production, but also on banana and sugar cane plantations. On the
B-BHC
8.60
Red snapper (Lutjanus guttatus)
p-pDDE
32.8
Pacifi c coast, agriculture is mainly carried out in the Choco and Valle del
Mirex
166.0
Cauca Departments. Variable concentrations of pesticides have been
B-BHC
2.156.9
Silver drum (Larimus argenteus)
Lindano
2.318.0
found in water, sediment and organisms at diff erent sites in Colombia.
Mirex
2.516.0
Concentrations of DDTs in surface sediments exceed international and
Lindano
16.0
Green Jack (Caranx caballus)
PpDDE
28.0
national standards, ranging between 2.2 and 66.7 ng/g (average of
B-BHC
760.3
Catfish (Arius ssp)
12.4 ng/g). The highest concentrations of pesticides, especially heptachlor
p-pDDE
103.5
and aldrin, were found at Tumaco and Pindo. Despite relatively limited
Lobster (Panulirus gracilis)
B-BHC
169.0
agricultural development on the Pacifi c coast of Colombia, pesticides
Scallop (Arquipecten circularis)
B-BHC
213.1
(Source: Álvarez et al. 1989, Álvarez & Manelia 1996)
found in coastal areas may originate from their use in anti-malaria
36
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
campaigns, the fumigation of illegal drug crops, and from substances
been reduced. In Costa Rica and Nicaragua, the processing of coff ee
used in wood treatment (Vélez et al. 2003). The impact of these pesticides
also contributes sediments to water bodies. Coastal industries discharge
on the local biota is unknown. The long-term eff ects on the sub-system's
effl
uents containing high concentrations of BOD, suspended solids, oils
ecosystems from the increasing use of pesticides and gliphosphate to
and nutrients (PNUMA 2001).
combat illegal drug cultures in Colombia are also unknown.
Rivers discharging into the Gulf of Fonseca deposit 3 million m3 of
Heavy metals such as mercury, copper, lead, cadmium, chromium and
sediment every year, resulting in a loss of benthic communities (CCAD/
zinc have also been found in water, sediments and marine biota in
IUCN 1999a). Sánchez (2001) and Rubio et al. (2001) reported high rates
Colombia (CPPS 2001). Concentrations of cadmium of between 0.39 and
of sedimentation along the Pacifi c coast of Nicaragua and in some
10.6 mg/kg were found in sediments at Buenaventura. These exceed
coastal areas of El Salvador where most of the 148 million tonnes of soil
international standards and Canadian guidelines for sediment quality
eroded from agricultural land in the 1990s entered the Gulf of Fonseca
and the protection of aquatic life. Other heavy metals found in high
(Sánchez 2001). In El Salvador, the rivers Paz, Sansonate, Lempa and
concentrations in sediments include lead and mercury (CPPS 2001).
Grande de San Miguel carry large amounts of suspended solids (Rubio
1994, Rubio et al. 2001). In Panama between 1970 and 1987, soil erosion
Suspended solids
increased by 60%, severely aff ecting aquatic ecosystems. Between 1981
Southwest Mexico
and 1994, the Panama Canal basin received large quantities of sediment
In Mexico, 259 540 tonnes of suspended solids and 378 130 tonnes of
from the rivers Boquerón (870 tonnes/km2/year), Pequeni (664 tonnes/
total dissolved solids (TDSs) were discharged in wastewater in 2000
km2/year) and Gatún (293 tonnes/km2/year) (Heackadon et al. 1999).
(PNUMA 2001). Most suspended solids found in aquatic systems
originate from increased erosion caused by a range of anthropogenic
The accumulation of sediments in the lower sections of the river basins
activities, particularly deforestation. Approximately 60% of Mexico
is impacting communities and ecosystems. In the Gulf of Fonseca,
(about 120 million ha) is aff ected by either severe or extremely severe
aquatic ecosystems have been smothered by sediments resulting
soil degradation. Water and aeolian erosion severely aff ects about
in a loss of biodiversity. Sedimentation has impeded access to some
30% and 43% of the country, respectively (CONAZA 1994, INEGI 1998).
port facilities (CCAD/IUCN 1999a); and it is aff ecting 35% of the coastal
As a consequence, the water bodies of the sub-system carry large
and marine protected areas, with coastal wetlands being especially
amounts of suspended solids, leading to severe sedimentation in
vulnerable (PNUMA 2001). Further, the growth of some coral reefs in
lakes and coastal wetlands. For example, Lake Chapala has received
Costa Rica is inhibited by sedimentation (PNUMA/IUCN 1998).
78 million m3 of sediment between 1930 and 1977 from the Lerma River,
reducing its storage capacity by 2.5 million m3/year (SEMARNAT 2004).
Pacifi c Colombian
Due to the short distance between the mountains and the sea in the
Central Equatorial Pacifi c
Pacifi c Colombian sub-system, rivers contain a high load of sediments
Municipal wastewater and run-off from catchment areas are the main
and other suspended materials. Extensive deforestation has exacerbated
sources of suspended solids in rivers and coastal waters. In 1999,
erosion, increasing further the sediments entering the rivers (Restrepo &
coastal settlements produced 116 270 tonnes of suspended solids and
Kjerve 2000, IDEAM 2002). The increased concentrations of sediments
179 590 tonnes of TDS (PNUMA 2001). Erosion due to deforestation
in river discharges are especially evident along the coast of the Valle
and poor agricultural practices is resulting in unknown quantities of
del Cauca Department (INVEMAR 2003b). Further, coastal settlements
sediment entering aquatic systems. The deforestation rate is almost
discharge wastewater containing approximately 10.7
tonnes of
400 000 ha/year, making it one of the highest in the world (Tribunal
suspended solids every day (Garay et al. 2001).
Centroamericano del Agua 2004). Pratt & Girot (1999) noted that erosion
aff ects the soils of over 25% of the sub-system's area. Consequently,
Solid wastes
most of the rivers transport large amounts of sediment to the lower
Southwest Mexico
reaches of the basin and the sea. In Panama, 25% of the eroded soil is
An estimated 15.3 million tonnes of solid waste is produced in the
estimated to settle in lakes Gatún and Alajuela (Franco 2001), which
Southwest Mexico sub-system every year; 6.75 million tonnes/year
have, as a consequence, lost 8% and 6% respectively of their useful
of which originates from coastal settlements (PNUMA 2001). Mexico
storage capacity. The fl ow rates and capacities of some of the rivers
generates over half the solid wastes in the GIWA Eastern Equatorial
in the sub-system, such as Choluteca, Lempa and Motagua, have also
Pacifi c region. In Mexico, the collection services cover 49% of cities
ASSESSMENT
37
with more than 100 000 inhabitants. Most solid wastes reaching the
material. Most radioactive materials include 132I, 3H, material for industrial
coasts of Mexico include organic matter of urban, agricultural and
purposes and non-destructive trials (192Ir, 60Co), as well as non-irradiated
industrial origin, which after oxidative processes become inorganic
fuel (a mixture of plutonium oxide or enriched uranium). In general,
stable compounds and can increase microbiological pollution (Páez
loads passing through the Panama Canal are classifi ed as `type B' or
1999). In 2002, the Ministry of Navy (SEMAR) collected 58 000 tonnes of
as having a `mid to high level of activity'. The material most frequently
solid waste from Mexican beaches.
transported through the Canal is depleted uranium hexafl uoride (UF ),
6
the transportation of which is strictly controlled.
Central Equatorial Pacifi c
The sub-system generates around 32 300 tonnes/day of solid waste
Radionuclides of natural and anthropogenic origin (40K and 137C) were
(Acurio et al. 1997). There is a lack of statistics on the coverage
found in the Gulf of Nicoya, Costa Rica, with concentrations exceeding
of collection services, except for in the urban areas of Costa Rica
international averages in the case of 40K (Loria et al. 2002). The source
(66%), Honduras (20%) and Guatemala (47%) where the services are
of this isotope could be agricultural activities along the Grande de
concentrated. Overall, the level of coverage is believed to be low. Most
Tárcoles River, whereas the presence of 137C is associated with nuclear
solid waste is disposed of inappropriately, some dumped directly into
tests conducted elsewhere.
water bodies. Wastes are not separated except, in some countries,
hospital wastes. Consequently, solid wastes accumulate in the outlets
Spills
of rivers such as Volcano-Pacifi c in Nicaragua, Virilla-Grande de Tárcoles
Southwest Mexico
in Costa Rica (Wo-Ching & Cordero 2001), and the rivers discharging into
The majority of oil spills are caused by operational failures in ports, during
Panama Bay. In El Salvador, wastes are disposed of in open areas without
the shipment of oil and gasoline, and by pipeline damage. Minor con-
treatment, often obstructing port activities (Rubio et al. 2001).
tamination is caused by oils and other hydrocarbons entering the sewer-
age system and then being discharged in coastal areas. These residuals
There are several environmental impacts caused by solid wastes,
can originate from burned oil from cars, the maintenance of vessels in
including increased BOD loads resulting from contained organic
dry docks, and motors used by industry. Polycyclic aromatic hydrocar-
matter. In sites receiving solid wastes, soils may become acidic and
bons are found in the sediments and coastal areas surrounding the port
leachates can contaminate aquifers. Improperly disposed solid wastes
of Salina Cruz (Oaxaca State in southern Mexico) where one of the most
also provide breeding environments for vermin, which may become
signifi cant petrochemical industries is located (Botello et al. 1998).
disease vectors. Debris can also harm wildlife through ingestion or
entanglement.
Central Equatorial Pacifi c
Most oil spills in the sub-system occur in ports and at storage sites. The
Pacifi c Colombian
1 900 vessels/year transiting the Panama Canal introduce approximately
The unplanned development of urban centres in the Pacifi c Colombian
200 tonnes of oil per year into the bay (Kiewcinsky 1986). Additionally,
sub-system has resulted in wastes being inappropriately disposed. As a
spills totalling 384 m3 were reported in the ports Balboa, Cristóbal and
consequence, waste accumulates on beaches. In 1996, 320 tonnes/day
Vacamonte in 1999. Most discharges were of diesel, bunker or cesspool re-
of solid waste was produced by communities along the Pacifi c coast of
siduals (PNUMA 2001). The trans-isthmus oil pipeline is another potential
Colombia (CPPS 2000). Buenaventura generated 250 tonnes/day (78%
source of oil pollution (PNUMA 1999). In Charco Azul, Gulf of Chiriqui, spills
of the total), 180 tonnes of which were collected and 70 tonnes were
of up to 800 m3 were reported in 1978 (CPPS 2000). In other areas of the
disposed of in open dumps. In Tumaco, only 40% (70 tonnes/day) of its
sub-system, oil spills total 600 m3/year. Spills total 28 m3/year in Guatemala
solid waste is collected. Another major source of solid waste is the timber
and El Salvador, and 32 m3/year in Honduras. Around 40-60% of the total
industry which generates around 570 000 m3/year (CPPS 2000).
spills are caused by the fi shing fl eet (Escobar 2003), whereas spills result-
ing from shipping accidents are uncommon and of low impact.
Radionuclides
There are no reports of radionuclide pollution in the region. However,
Pacifi c Colombian
there is a potential risk of nuclear pollution from the transport of
Several minor spills that occurred in 1976 and 1998 in Ecuador aff ected
radioactive material through the Panama Canal (Gibbs in Escobar 2000).
the Colombian coasts of Nariño and Valle del Cauca, including Gorgona
It is estimated that 10 vessels per month carry radioactive loads through
Island and Tumaco (MMA 2002b). Exploitation, refi ning and transport
the Canal, each holding 12-14 containers with 30-60 tonnes of nuclear
activities have resulted in chronic pollution, particularly around Tumaco
38
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
(Vélez 2003). In the late 1990s, the average hydrocarbon concentrations
Central Equatorial Pacifi c
were recorded as 25 µg/l in coastal waters, 1.18 µg/g in sediments and
Untreated domestic and industrial wastewaters are major sources of
7.45 µg/g in mollusc bivalves (Garay et al. 2002). Between 1986 and 1999,
pollution in the sub-system and a signifi cant cause of enteric diseases.
there were 654 acts of sabotage to the Colombian oil pipeline, which
As many as 12 diseases produced by pathogenic micro-organisms are
caused the spillage of 336 420 m3 of oil into the environment, resulting
linked to polluted waters. They aff ect mainly the vulnerable groups
in remediation costs of 37.7 million USD (Vélez 2003).
of the population, especially children (PNUMA 2001). Acute diarrheic
disease (ADD) is the main cause of infant mortality (children under fi ve
Socio-economic impacts
years old). In the past 30 years, 5 million children died from this disease,
Southwest Mexico
although the mortality rate has decreased signifi cantly in recent years
In Mexico, 74.5% of the population had access to sanitation services in
(Tribunal Centroamericano del Agua 2004). ADD and other water-
the form of a sewerage system (58.4%) or in situ solutions (14.1%) in 2000
related diseases are still the main cause of the high rates of morbidity
(OPS/OMS 2001a). This means that a total of 26.4 million inhabitants
and mortality in the sub-system. The current infant mortality rate is
dispose their wastewater and excreta inappropriately. The proportion
36, decreasing to a quarter of the rate in 1970 when it was 135.
of the population with sanitation services or in situ solutions in Mexico
In the case of Costa Rica, which has the highest living standards in the
is lower than the average for the LAC (79.2% and 30.6% respectively)
sub-system, it was 16 in 1998. In Nicaragua, which has the lowest per
(OPS/OMS 2001a).
capita income, the rate decreased from 165 in 1970 to 48 in 1998.
Despite this progress, infant mortality rates remain comparably high,
The economic impact of water pollution in Mexico has not been fully
even in Costa Rica (Ballesteros 2003).
examined. Qualitative evidence suggests that tourists are discouraged
from visiting polluted areas and are selecting alternative tourism desti-
Cholera is another disease aff ecting the population of the sub-system.
nations (Muñoz-Pineda pers. comm.). Coastal water pollution negatively
During the 1990s, the Pan-American Health Organization recorded
aff ects diving and other forms of tourism, as well as the commercial fi sh-
254 077 cases of cholera. Countries with the most cases are Guatemala,
eries, as it is degrading aquatic ecosystems, particularly coral reefs and
33.9%; Nicaragua, 12.8%; and El Salvador, 12%. A total of 27 412 cases of
their associated living resources (Coral Reef Alliance 2003).
dengue fever were reported in 2001, of which 991 were hemorrhagic
dengue fever which killed 28 people (OPS/OMS 2004). Because
In Mexico, microbiological pollution in coastal waters poses health risks
sanitation coverage is not increasing in line with population growth,
for bathers as exposure can result in disease, including gastroenteritis,
the prevalence of diseases will increase.
acute febrile respiratory illness and hepatitis. Children, the elderly and
individuals with weak immune systems are particularly vulnerable;
The economic costs of environmental degradation caused by pollution
even with treatment some of these diseases can be fatal (Hancock &
in the sub-system have not been suffi
ciently researched. The total cost
Gilmore 2004).
of pollution in the Gulf of Nicoya, Costa Rica, has been estimated at
203 million USD per year (Castro et al. 2000). These costs include the
Digestive tract diseases related to the consumption of contaminated
treatment of wastewater and solid wastes of domestic and industrial
water or shellfi sh include acute gastroenteritis, typhoid fever, hepati-
origin and the loss of revenues by productive activities such as tourism,
tis A and cholera. Nasal and pharyngeal diseases are also associated
fi shing and farming. Every year between 1 000 and 2 000 persons in
with poor water quality. Gastroenteritis is the most common disease
Central America are poisoned by pesticides; the associated medical
aff ecting children, the poor and other vulnerable groups (CPPS 2001,
costs are between 32 and 92 USD per person, depending on the type
UNEP 2000). In general, gastrointestinal disorders are the main cause
of toxin (García 1998). Litter accumulation has reduced the aesthetic
of infant mortality.
value of coastal sites, thus aff ecting tourism and posing a permanent
risk for fi shing and maritime traffi
c.
Eutrophication may increase the frequency of HABs in Mexican Pacifi c
waters. Toxic HABs were reported in Mazatlan in 1979 and Oaxaca-
Pacifi c Colombian
Chiapas in 1989 (Cortés et al. 1993). More than 300 cases of paralytic
The impact of pollution on human health in the Pacifi c Colombian
shellfi sh poisoning (PSP) have occurred in Mexico with 17 mortalities.
sub-system is considered as moderate to severe. Several private
Closed seasons during the HAB events have resulted in economic losses
enterprises that provide freshwater and sanitation services in the Valle
of 200 million USD to the fi sheries industry (Schoijet 2002).
del Cauca Department have been charged retributive fees (pollution
ASSESSMENT
39
T
C
A
tax). Recently, the government institution Corporación Autónoma
Habitat and community
IMP
Regional del Valle del Cauca began legal proceedings against four of
modification
the fi ve enterprises operating in this department because they have
failed to pay the retributive fees since 1997. The fees are owed for the
Habitat and community modifi cation is being caused by a range
discharge of 68 700 kg/day of pollutants into water bodies in the Cauca
of human activities including deforestation, fi shing, tourism and
River basin (El País 2004).
aquaculture. Lakes, rivers, mangroves, benthic ecosystems and coral
reefs have been degraded, but no quantitative data is available. Data
In terms of morbidity, the low sanitation coverage seriously aff ects the
related to the loss of native species or changes in community structure
health of the population. Between 5 and 10% of deaths are related to
caused by alien species is similarly unavailable.
the lack of sewerage services, the inappropriate disposal of wastes and
poor freshwater quality. About 50 000 people die annually from water
Habitat and community modifi cation was assessed for the Central
related disease in Colombia. The two major causes of infant mortality
Equatorial Pacifi c and Pacifi c Colombian sub-systems.
are gastroenteric diseases and malnutrition, which also increase the vul-
nerability of children to other infectious diseases (INDERENA 1992). The
Loss of ecosystems
population in the Pacifi c region of Colombia has the highest risk of infant
Central Equatorial Pacifi c
morbidity and mortality (Yepes 1990). The infant mortality in the Choco
Aquatic ecosystems and habitats are severely aff ected by sedimentation,
Department is 150, which is three times the national average, and the
particularly corals reefs at Punto Islotes and Agua Dulce in Costa Rica, as
life expectancy is 12 years lower than in Cali City (INDERENA 1992).
well as some shallow water coral reefs at Baru and Chiriqui in Panama. At
Iguana Island (Panama) around 80% of the coral reef has been destroyed
Conclusions and future outlook
by oil spills, whereas the coral reefs at Coiba and in the Gulf of Chiriquí
Wastewater discharged without treatment through the sewerage
have been partly destroyed by trawlers (Escobar 1996). During the warm
network or directly into water bodies is the most widespread pollution
phase of the El Niño events in 1982-1983 and 1997-1998, widespread
issue. There is a low level of sanitation coverage in most of the countries
coral bleaching occurred in Panama (PNUMA 2001).
in the Eastern Equatorial Pacifi c region. In general, the coverage of
sanitation and drinking water services has not grown in line with
Wetlands and mangroves are impacted by solid wastes, such as in the
population growth and urban development. As a consequence, water-
Volcano-Pacifi c basin in Nicaragua, La Unión Bay in the Gulf of Fonseca
related diseases are increasingly prevalent with acute diarrheic disease
and in the lower sections of the river basins of Matasnillo, Tapias,
the main cause of morbidity and infant mortality. Poorer communities,
Juan Díaz, Río Abajo, Chilibre and Chilibrillo in the Gulf of Panama.
children and the elderly are the most vulnerable groups.
An estimated 98% of estuaries in the sub-system are aff ected by
sedimentation, wastewater and agro-chemicals (PNUMA 2001).
Pesticides and fertilisers are used intensively in agriculture. They are
responsible, in combination with domestic wastewater, for causing
Mangrove forests have been used for several purposes, including
eutrophication and toxic pollution in coastal areas which is impacting
aquaculture, agriculture, urbanisation, fi rewood, construction and
marine ecosystems and thus the food security of the coastal
to obtain salts and tannins. In the Gulf of Fonseca, mangrove forests
population. Although there is a dearth of information regarding the
have been cleared for shrimp ponds, and salt and tannin production.
eff ects of pollutants in the coastal zone of the region, it is expected
In 1993, 89 200 m3 of fi rewood from mangrove forests was used for salt
that pesticides, heavy metals and other pollutants are accumulating
extraction (1 tonnes of salt requires 3.5 tonnes of wood). The extent
in coastal areas and are impacting marine biota. Pollution has a direct
of the mangrove area has been reduced from 104 911 ha in 1976 to
impact on human health as a result of defi ciencies in freshwater supply,
69 109 ha in 1997, while the shrimp farming area has increased from
sanitation and wastes collection services. Pollution is threatening
8 000 ha in the 1980s to 29 370 ha in 1997 (CCAD/IUCN 1999a). By 1994,
economic development, particularly tourism.
Honduras had lost around 12% of its mangrove forest due to aquaculture
(Figure 17). Prior to the 1960s, there were 500 000 ha of mangrove in the
central provinces of Herrera, Los Santos and part of Cocle (Panama),
but by 1988 only 176 000 ha remained. In a 30-year period, 5 647 ha of
mangrove forest were cleared for agricultural purposes in Soná, 1 345 ha
in Veraguas province and 2 157 ha in Chiriqui (López et al. 1996). The
40
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
consequences of mangrove destruction include increases in coastal
Mangroves are the most impacted coastal ecosystem, especially at
erosion, higher penetration of the saline wedge in some estuaries,
Puntarenas, Costa Rica; in El Salvador between the outlets of the riv-
soil salinisation and, in particular, a decrease in biological productivity
ers Paz and Jiquilisco; in the estuaries of El Zapote, San Diego and
which directly impacts the artisanal fi shery (PNUMA 2001).
Jaltepeque; and near Maculita Beach (Rubio et al. 2001). In Nicaragua,
the most impacted areas are the estuaries of El Realejo, Jiquilillo and
Pacifi c Colombian
Chichigalpa (Sánchez 2001); mangrove forests in the lower basin of riv-
Mangrove and alluvial forests are the most aff ected ecosystems.
ers draining into Panama Bay (Franco 2001); and mangroves in the Gulf
Between 1980 and 1990, agriculture expanded by 108 623 ha at the
of Fonseca (CCAD/IUCN 1999a). Among the measures adopted by the
expense of forests, while at the same time, the Andean forests were
governments of the region to protect their biodiversity is the creation
reduced by 23 302 ha. Mangrove forests are unsustainably exploited
of protected areas. However, around 35% of the coastal and marine pro-
as they are valuable resources for humans (República de Colombia et
tected areas had deteriorated by 2001 due to a variety of causes, such as
al. 2002). Mangroves have been destroyed mainly to build aquaculture
sedimentation, mangrove clearing, pollution and overfi shing (PNUMA
infrastructure (Conservación Internacional 2004), but also due to logging,
2001). The status of mangrove forests on the Pacifi c coast is considered
in-fi lling, construction, the accumulation of wastes and wastewater
to be vulnerable, in the Gulf of Fonseca and northern dry coast as en-
contamination, among other threats (Table 17) (MMA 2002b).
dangered, and in the southern part of the dry coast as critical. Only a
small proportion of the Pacifi c mangrove forests are relatively stable.
Table 17
Main activities aff ecting mangrove forests in the Pacifi c
The modifi cation of mangrove and estuarine ecosystems has aff ected
Colombian sub-system.
important fi sh nursery and recruitment grounds. Further, trawling is al-
Activities/causes
Choco
Valle
Cauca
Nariño
Sedimentation
tering benthic habitats in coastal waters.
Roads, airports, maritime and port infrastructure
Expansion of the urban frontier
Pacifi c Colombian
Expansion of agriculture and livestock frontier
Habitat modifi cation is evident in wetlands as well as natural forests
Eutrophication
(IDEAM 2002). These ecosystems are degraded more than on the
Logging, filling and construction
plains as concessions have been granted to several enterprises to ex-
Inappropriate forestry
tract wood pulp from both wetlands and rainforests (Conservation
Pollution by hydrocarbons
International 2004). Coastal ecosystems, in particular mangroves, are
Shrimp farms
considered fragile and vulnerable as a result of high rates of erosion and
Natural disasters
(Source: MMA 2002c)
habitat fragmentation. These issues raise concern about the sustainabil-
ity of the region and its resilience to the current rates of exploitation
Anthropogenic activities are also reducing biodiversity; for example,
(Conservation International 2004).
the richness and abundance of coprophages beetles has declined
(Family Scarabaeidae, Subfamily Scarabaeinae) (República de Colom-
Although several alien species are known to have been introduced
bia et al. 2002).
into Colombian waters, there is limited information regarding their
distribution and impact on aquatic ecosystems. However, introduced
The forests in the river basins of the sub-system have been
species of cichlids, gerrids and shrimps, among others, may be aff ecting
extensively modifi ed; 22.1% (2.23 million ha) of the total surface area
the biodiversity of the sub-system. In some cases, these species are
of the sub-system has experienced moderate intervention and 12.3%
introduced by government institutions without consideration of
(1.24 million ha) is degraded (República de Colombia et al. 2002). The
the environmental consequences (Conservation International 2004).
deforestation rate in the region over the past 17 years has been around
Acrostichum aureum, an alien fern species, has been detected in
110 000 ha/year, which has caused the loss of more than half of the sub-
deforested mangrove zones (MMA 2002b).
system's original forest (Conservation International 2004).
Socio-economic impacts
Modification of ecosystems
The economic impact of the loss and modifi cation of ecosystems is
Central Equatorial Pacifi c
insuffi
ciently documented. According to the regional team, habitat
Several aquatic environments and communities are aff ected by envi-
modifi cation has reduced income and investment opportunities. The
ronmental deterioration in the Central Equatorial Pacifi c sub-system.
loss and degradation of mangrove forests has compromised their
ASSESSMENT
41
ability to provide valuable resources for local communities. Around
other forests, and will continue to increase in signifi cance due to high
820 000 people depend directly on the Gulf of Fonseca's resources.
population growth rates, particularly in coastal areas. The future out-
Despite the importance of mangroves in the Gulf as nursery and
look is uncertain and will depend on the success of current and future
recruitment areas for important commercial fi sheries, large areas
conservation and sustainable initiatives.
of forest have been destroyed by a variety of human activities (see
Figure 17). A study by CCAD/IUCN (1999a) showed that the number of
artisanal fi shermen has increased but fi sh production has decreased.
T
C
A
The resultant lower incomes from fi shing have led to extreme poverty in
Unsustainable exploitation of
IMP
some communities. The expansion of aquaculture in the Gulf of Fonseca
fish and other living resources
is creating social tensions as the farmers are restricting the access of
artisanal fi shermen to traditional fi shing areas (CCAD/IUCN 1999a).
The unsustainable exploitation of fi sh and other living resources
was assessed in the Central Equatorial Pacifi c and Pacifi c Colombian
sub-systems. There has been an increase in fi shing eff ort in both the
industrial and artisanal sectors, particularly for high-value species such
as shrimp and tuna. Overfi shing and the use of destructive fi shing gear
G U L F O F
F O N S E C A
have resulted in a decline in recruitment and the degradation of the
habitat of some commercial species.
P A C I F I C
Marine fi sheries account for 92% of the total catches in the sub-system
O C
(FAO 2002b). Panama is the leading fi shing country with 77% of the
E A
total volume, followed by Costa Rica with 11.6% (Table 18). The main
N
commercial fi sheries include tuna and small schooling fi sh, such as the
California sardine (Sardinops sagax) and anchovy (Engraulis spp.). There
Mangrove
© GIWA 2005
is also an upwelling area off Panama where a locally important stock
Figure 17 Remaining mangrove areas (in purple) in the Gulf of
of the Central Pacifi c anchovy (Cetengrauilis mysticetus) is exploited
Fonseca.
(WCMC 1996).
(Source: CCAD/IUCN 1999b)
No health impacts associated with habitat modifi cation have been re-
Fishing is one of the main sources of income for inhabitants in the
ported. The construction of dams and reservoirs for hydroelectric gen-
coastal area of the Pacifi c Colombian sub-system. The major fi shing
eration causes habitat fragmentation and increases the water surface
ports on the Pacifi c coast are Tumaco, Guapi, Buenaventura, Nuqui
area where tropical disease vectors can develop. Habitat degradation
and Solano Bay (INDERENA 1992). The fi sheries industry is comprised
is eff ecting rural populations that depend on wetland and marine re-
of three sectors: industrial, artisanal and aquaculture. The artisanal
sources for their subsistence. The social and community impacts are
and industrial sectors account for 53.9% and 46.1% of total catches,
expected to increase in severity due to the continued modifi cation of
respectively (INDERENA 1992).
ecosystems.
Table 18
Total marine catches in the countries of the Central
Equatorial Pacifi c sub-system.
Conclusions and future outlook
Average production
The extent and structure of coastal ecosystems has changed as a result
Pacific Ocean (tonnes)
Country
(tonnes)
%
of human activities. Mangrove and several other forest communities,
1995
1997
1999
2001
1995-2001
especially in fl ooding lowlands, have been overexploited since the sec-
Costa Rica
15 846
25 409
23 555
32 917
24 431
11.6
ond half of the 20th century and they are now on the brink of collapse.
El Salvador
10 747
9 089
7 841
16 065
10 935
5.20
Guatemala
3 838
1 490
8 930
2 450
4 177
1.98
These ecosystems have lost the capacity to provide basic necessities
Honduras
864
4 002
1 702
3 044
2 403
1.14
for human well-being. Increased sedimentation, primarily as a result of
Nicaragua
4 500
5 432
9 662
8 304
6 974
3.34
deforestation, is modifying the aquatic ecosystems of the sub-system.
Panama
151 219
147 295
111 140
230 390
160 011
77
Loss of mangrove forest is the best documented case of habitat destruc-
Total sub-system
187 014
192 717
162 830
293 170
208 931
100
tion in coastal areas. Urbanisation has also aff ected both mangrove and
(Source: FAO 2002b)
42
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Overexploitation
exploitation of fi shing resources is considered unsustainable in the
Central Equatorial Pacifi c
sub-system.
The increasingly large catches of fi sh have become unsustainable. In
Nicaragua, for example, annual catches increased from 4 235 tonnes in
The report on the State of Marine and Coastal Resources of Colombia
1984 to 23 259 tonnes in 1998, and in Honduras they increased by 250%
(INVEMAR 2003c) reported that catches of mackerel, snappers and sharks
over the same period (Pratt & Girot 1999). Coastal species such as lobster,
decreased in 2001, whereas catches of tuna and other fi sh increased.
snail and sea urchin are considered depleted. The Central Pacifi c anchovy
Catches of Blue crab (Cardisoma guanhumi) increased from 37 tonnes in
is fully or overexploited in Panama (WCMC 1996). The increase in catches
2000 to 716 tonnes in 2001. High-value resources such as jumbo shrimps
of anchovy and the Californian sardine will lead to the collapse of these
(Penaeus sp.) decreased from 2 686 tonnes in 1999 to 4 tonnes in 2001,
fi sheries (FAO 1997). A signifi cant proportion of tuna production is by
and other shrimps from 3 826 tonnes to 1 575 tonnes between 2000
foreign fl eets, such as those from South Korea, Japan, the United States
and 2001. Mollusc production decreased from 864 tonnes to 7 tonnes
and Venezuela (Sea Around Us Project 2002).
between 1997 and 2001. Squid catches decreased from 295 tonnes in
1996 to 76 tonnes in 2001 and clams decreased from 10 tonnes in 2000
Most shrimp populations in the sub-system are considered by the FAO to
to only 1 tonnes in 2001. Unfortunately, there is a lack of fi sheries data
be fully or overexploited. In Costa Rica, the majority of pelagic and coastal
to investigate the long-term trends of fi sh catches and stocks. A risk
benthic fi sh species are also overexploited. Catches of shark, marlin, sailfi sh
analysis of the Pacifi c artisanal fi sheries concluded that several species
and some species of tuna have decreased steadily since the 1950s. Today,
of fi sh, molluscs and crustaceans are at a high risk of overexploitation
some 85% of pelagic production is caught beyond the Economic Exclu-
(Rueda et al. 2003).
sive Zone (EEZ) (Sinergia 69 unpublished).
There are around 15 000 artisanal fi shermen along the Pacifi c coast of
In the Gulf of Fonseca, some molluscs and crustaceans associated with
Colombia. In recent years, there has been an increase in fi shing eff ort,
mangrove and rocky ecosystems are overexploited by the artisanal
most likely caused by the high level of unemployment in rural areas.
fi shery, and several others such as the oyster Ostrea iridescens, Green
There has been migration from rural inland areas to the coast in search
lobster (Panulirus gracilis) and the crab Menipe frontalis are at their limit of
of food, security and an income (INPA 2000). The increased coastal
exploitation (CCAD/IUCN 1999a).
population puts further pressure on fi sheries resources which, in turn,
decreases the per capita supply of protein.
Pacifi c Colombian
According to FAO (2004c), catches of marine fi sh, crustaceans, molluscs
During the 1970s, the trade in marine turtle skins resulted in the death of
and other marine living resources decreased in Colombia between
thousands of Olive Ridley turtles (Lepidochelys olivacea). The turtles were
1992 and 2000 (Figure 18). Catches of fi sh in the continental waters
caught mainly to the south of Buenaventura and towards the border
of the Choco region have also steadily declined. The current rate of
with Ecuador (MMA 2002a). From March until June during this period,
between 500 and 3 000 turtles were slaughtered every day (Olarte 1987
in MMA 2002a). Only a small part of the turtle was used (neck and pecto-
140 000
ral fi ns); only 7 kg of a 50 kg turtle (MMA 2002a). In 1996, the use of turtle
120 000
exclusion devices (TEDs) was made obligatory for the Pacifi c trawl fl eet
100 000
and the retention of captured turtles was prohibited (FAO 2003).
onnes)
80 000
(t
Excessive by-catch and discards
t
ch
a
60 000
C
Central Equatorial Pacifi c
40 000
The shrimp trawl fi shery has the highest rate of discards due to the use
20 000
of non-selective fi shing gear. The catching of shrimp larvae for shrimp
ponds is reducing the recruitment of several commercial species and
0
1992
1993
1994
1995
1996
1997
1998
1999
2000
threatening the long-term sustainability of both aquaculture and artisanal
Year
fi shing, as observed in the Gulf of Fonseca. Shrimp aquaculture requires
Figure 18 Total catches of coastal marine resources in the Pacifi c
4 billion post-larvae annually; for every shrimp post-larvae caught,
Colombian sub-system.
(Source: FAO 2004c).
nine larvae of other commercial species are discarded. Discards can
ASSESSMENT
43
include larvae of up to 30 diff erent organisms (CCAD/IUCN 1999a). There
waters and 34 industrial vessels operating in deep waters (Ustate 2002).
are no assessments of marine mammal by-catch, although Palacios &
The full eff ect of trawling nets on benthic communities is unknown.
Gerrodette (1996) suggest it is similar to other parts of the Pacifi c coast
of South America.
Decreased viability of stocks through pollution
and disease
Several demersal species are caught as by-catch in the artisanal
Central Equatorial Pacifi c
fi shery of El Salvador and Guatemala. The depletion of these stocks is
Díaz & Fernández (1994) found that fi shing activity in the Gulf of Nicoya
extremely detrimental to the sharks that prey on them (Sea Around Us
(Costa Rica) has decreased by over 50% due to wastewater and other
Project 2002). In the Gulf of Fonseca, the shark fi shery is showing signs
pollutants discharged by the Grande de Tárcoles River basin. There
of depletion, especially species of the genus Carcharrinus and Spyrna.
are no records in other areas of the sub-system of sickness in fi sh and
Other species at their exploitation limit include several species of the
marine organisms caused by pollution. Decreased catches are mainly
families Lutjanidae, Scianidae, Centropomidae and Serranidae (CCAD/
attributed to overfi shing and the infl uence of El Niño events.
IUCN 1999a).
Pacifi c Colombian
Pacifi c Colombian
Landings of shrimp have changed dramatically in the last fi ve years.
Shrimp trawling nets and gillnets are considered the main threat to
The viability of the stock is aff ected by both overfi shing and white spot
marine turtles in Colombian waters. Approximately 8 230 marine turtles
disease, a virus that has impacted shrimp farms since 1999 causing
were captured by the trawling fl eet in 1998 (Duque-Goodman 1998 in
a downturn in the profi tability of the aquaculture sector (González
MMA 2002a), including the Olive Ridley turtle and Black turtle (Chelonia
2002).
agassizzi), 23-65% of which died (MMA 2002a). Some studies on by-catch
from the shrimp trawling fi shery in the Colombian Caribbean demon-
Impact on biological and genetic diversity
strated that the ratio of fi sh caught to shrimp is 10-12:1, with 75% of the
Central Equatorial Pacifi c
fi sh discarded (Santodomingo & Rueda 2003). Although similar studies
Several alien species, notably cichlids, have been introduced for
have not been carried out on the Pacifi c coast of Colombia, information
freshwater aquaculture. In Nicaragua, the main species used in
on shrimp trawling in Ecuador, south of Colombia, shows the same rate
aquaculture is Nile tilapia (Oreochromis niloticus). The Rainbow trout
of discards as on the Caribbean coast of Colombia (Little & Herrera 1991).
(Oncorhynchus mykiss) is raised in El Salvador, Panama and Costa Rica.
Purse seine gear, which was intensively used between 1985 and 1999,
In the Panama Canal basin, several alien species of fi sh, such as the
was also found to have signifi cant by-catch; the target species account
Common carp (Ciprinus carpio) and the Peacock bass (Cichla ocellaris),
for only 32% of the catch (Santodomingo & Rueda 2003).
are found in the Chagres River and several species of Tilapia have been
reported in Lake Gatún. Their impact on biological and genetic diversity
Destructive fishing practices
is inadequately documented. It is known, however, that several alien
Central Equatorial Pacifi c
species are highly adaptive and compete successfully with local fauna.
There is no quantitative information on the use of destructive fi shing
Various species of the genus Tilapia have become widespread in some
gear in the sub-system. Some national reports presented during the
coastal areas. Fisheries authorities have established procedures for the
preparatory meeting of the Plan of Action for the Protection of the
use of alien species in the aquaculture industry.
Marine Environment and Coastal Zones of the North East Pacifi c (2001)
provided information about the use of dynamite and barbasco (fi sh
Pacifi c Colombian
poison from the roots of Lonchocarpus nicou) by artisanal fi shermen
The introduction of alien species either intentionally for farming or
in estuaries. The use of fi ne mesh nets for shrimp larvae is particularly
unintentionally via ballast waters is poorly studied in Colombia. Around
common in the Gulf of Fonseca (CCAD/IUCN 1999a). All these methods
96 species of fi sh are known to have been introduced into Colombian
are illegal and forbidden throughout the sub-system.
waters, especially species of the families Salmonidae, Cyprinidae and
Cychlidae (Alvarado & Gutiérrez 2002).
Pacifi c Colombian
There is no available information on destructive fi shing practices in
Socio-economic impacts
Colombia other than on trawl nets used by the shrimp trawl fl eet. In
Fishing is one of the most important economic activities on the coast,
2000, the Pacifi c trawl fl eet comprised 64 vessels operating in shallow
providing a major source of employment and income. The depletion
44
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
T
C
A
of fi sh stocks will have a direct impact on coastal populations, reducing
Global change
IMP
income and increasing unemployment, thus weakening social stability
and food security.
Global change in the region may increase the severity of El Niño events,
including longer and more widespread droughts. Extreme climatic
There are no reports of human health impacts caused by the
conditions signifi cantly impact economic activities and social well-
unsustainable exploitation of the fi sheries. Around 28% of children
being in the region. The El Niño of 1997-1998 increased the frequency
under fi ve years old are undernourished in the Central Equatorial Pacifi c
of cyclones in Mexico and the Caribbean, with hurricanes reaching
sub-system with protein defi ciencies. The consumption of fi sh per
the Pacifi c side of Central America. These conditions may increase in
person is relatively low (between 2 and 10 kg/year). Fishing resources
frequency and intensity as a consequence of global climate change.
have the potential to provide cheap and high quality protein.
According to Intergovernmental Panel on Climate Change (IPCC)
projections, the region's average temperature will increase by 0.5-2°C
The shrimp trawl fi shery in shallow waters was the most important
and the sea level will rise by 25-50 cm between 1990 and 2100. No
fi shery until the mid-1980s when it reached its Maximum Sustainable
information was available about the issues of increased UV-B radiation,
Yield (MSY). However, overexploitation, pollution and the development
and changes in ocean CO source/sink function.
2
of forestry have reduced its importance (INPA 2000). During the second
half of the 1980s, fi sheries authorities restricted fi shing activities until
Changes in the hydrological cycle
an assessment of the resource was undertaken. As a result of this
Central Equatorial Pacifi c
assessment, an annual closed season for the shrimp trawl fi shery has
According to IPCC, the eff ects of global change on the countries of the
been implemented since 1991. The shrimp trawl industry now focuses
sub-system are likely to be more intense on the Pacifi c side of Central
on fi sh and other more abundant resources with lower operational costs
America where sea surface water temperatures are expected to increase
(INDERENA 1992).
and rainfall to decrease. There will be prolonged droughts, especially
during the El Niño. A summary of the national reports by Girot & Jiménez
Conclusions and future outlook
(2003) is shown in Table 19.
The fi sheries resources of the Eastern Equatorial Pacifi c region are
Table 19 Diff erent sceneries of global change in the Central
signifi cantly depleted. The industrial fi shing sector targets small,
Equatorial Pacifi c sub-system in 2100.
schooling fi sh, which are used in fi shmeal and oil production (Sea Around
Months with
Changes in tem-
Changes in
Us Project 2002). Tuna, especially yellowfi n, skipjack and albacore, are
Country
most severe
Affected zones
perature (°C)
rainfall (%)
changes
also targeted. The large pelagic fi sheries are exploited at their MSY along
Motagua Valley toward
the coast of the majority of the region. The overexploitation of fi shing
+3.5 °C
Cochunatamos sierra
Guatemala
-30%
July-September
Increase of dry season
and Southeast of the
resources is adversely aff ecting coastal and marine ecosystems. Coastal
country
areas support an intensive shrimp trawl fi shery which impacts benthic
+0.9 a +3.7 °C
-8% a -37%
May-June
Gulf of Fonseca slope
communities and has signifi cant quantities of by-catch and discards.
Honduras
In the Central Equatorial Pacifi c, around 52% of artisanal fi sheries
Southeast of the coun-
+0.8 a + 3.3 °C
-8% a -36%
November-April
production and 36% of the shrimp trawling fi shery is from the Gulf of
try and Coco basin
Fonseca. Operational costs have increased due to the reduction in the
Increase of dry season
El Salvador
-36.6% a +11.1%
January-March
All the country
+2.5 a +3.7 °C
availability of resources. The long-term food security of the coastal
population is jeopardised by the reduction in fi sheries resources.
Annual vari-
Pacific: North of Chinan-
Nicaragua
+3.0 °C
- 36.6%
ations
dega and León
Fisheries management is failing to control fi shing eff ort and illegal
+3.8 °C
-63.0%
Guanacaste
fi shing. Unreliable statistics aff ect the credibility of assessments
North and Northeast
and prevent fi sheries managers from making informed decisions.
Costa Rica
+3.2 °C
-69.0%
March-May
zones
Future conditions will depend on the successful implementation of
Pacifi c Agenda 21 (see Annex III) and several other conservation and
+3.5 °C
-49,0%
South of the country
development projects.
Annual vari-
Panama +0.8
°C
-1,8%
Coastal Pacific basins
ations
(Source: Girot & Jiménez 2003)
ASSESSMENT
45
In Nicaragua, the annual mean temperature will increase from 27-28°C
predicted under IPCC scenarios, presenting the results at the Fifth An-
to 30-31°C in the Pacifi c areas of Chinandega and León, and rainfall will
nual Session of the Commission on Sustainable Development. In Costa
decrease by 36.6%. Annual rainfall will be less than 500 mm in most of
Rica, seawater will penetrate inland by 150 m at Puntarenas, fl ooding
the Central Equatorial Pacifi c and 800-1 000 mm in the south. By 2100,
105 ha (60% of the urban area). If the sea level rises by 1 m, the sea
cities on the Pacifi c slope will have a 25% water defi cit and a reduc-
will reach up to 500 m inland, fl ooding 300 ha (90% of the urban area)
tion in rainfall of 21% (Girot & Jiménez 2003). In Honduras, a vulner-
(MINAE 2000). In El Salvador, it is estimated that around 10% (149 km2)
ability analysis of water resources shows a signifi cant reduction in the
of its territory would be fl ooded if the sea level rises by 13 cm and up to
discharges of the river basins of Choluteca and Humaya. For the Cho-
27.6% (401 km2) if it rises by 1.1 m (MARN El Salvador 2000). In Panama,
luteca River, under a scenario of a 1-2°C temperature increase and 10-
sea-level change will result in fl ooding, the displacement of wetlands,
15% increase in rainfall, run-off during the rainy season will increase by
increasing coastal erosion and the salinisation of estuaries and aquifers.
18-20%. In contrast, discharges will decrease by between 31% and 21%
Storms will become more frequent, intertidal areas will increase in area
if there is a reduction in rainfall of 10-15% and a temperature increase
and sedimentation patterns will change resulting in the fl ooding of
of 1°C (SERNA in Girot & Jiménez 2003). In Guatemala, according to IPCC
low-lying areas (ANAM 1994). So far, there is no authoritative evidence
scenarios, potential temperature and rainfall changes will have the larg-
of sea level change in the sub-system.
est impact on an area containing 40% of the cloud forests, resulting in
increased river discharges (MARN Guatemala 2001). In El Salvador, the
Pacifi c Colombian
forecasted intensifi cation of dry periods by 2100, in combination with
Recent studies have highlighted the vulnerability of the sub-system
high population growth, could have severe impacts on the availability
to sea level rise (INVEMAR 2003a). Tumaco and Buenaventura are
of water for the country's ecosystems and population (MARN in Girot
considered at high risk. The annual rate of sea level rise is estimated to
& Jiménez 2003).
be 2-5 mm (Lozano & Pabón 2005).
Pacifi c Colombian
Socio-economic impacts
The average water availability in Colombia is estimated to be 57 000 m3/
There are severe economic, health and social impacts associated with
person/year (IDEAM 2001) and average annual rainfall and surface run-
natural disasters. They often result in migration, disease epidemics, a
off is more than three and six times the global average, respectively.
loss of income and employment, human injuries and mortality, and
It may, therefore, be inferred that global change has not signifi cantly
damage to property. There is no available data which links socio-
aff ected the hydrology of the Pacifi c Colombian sub-system. However,
economic problems in the sub-system with global changes. However,
Pérez et al. (2005) found positive trends in minimum and average
severe social and economic impacts are expected to result from the
temperatures throughout Colombia and a reduction in the discharge
increasing frequency and intensity of extreme climatic events.
of the major river basins. This was linked to a shift in the annual cycles
of several climatic variables. Such fi ndings demonstrate that climatic
Sea-level rise will impact coastal infrastructure and economic activities,
changes are beginning to aff ect the hydrological regime of the Pacifi c
such as tourism. Global warming is expected to cause the tropicalisation
Colombian sub-system.
of the marine environment which will alter the distribution and
composition of marine resources, signifi cantly impacting the regional
It is unknown how changes in ocean circulation may infl uence the sub-
fi sheries. The increased severity of El Niño periods will have disastrous
system but it is evident that ocean induced events such as the El Niño
eff ects on the economy of the countries in the region. Higher surface
and/or La Niña change the rainfall regime; such events are expected
water temperatures will change the productivity of upwelling areas,
to occur more frequently and intensely due to global warming (IPCC
thus aff ecting the food web of the region's ecosystems.
2001).
The sectors impacted by global change are thought to be agriculture,
Sea-level change
fi shing and hydroelectricity, particularly during El Niño events. In 1992,
Central Equatorial Pacifi c
a drought period necessitated the restriction of electricity, which
Sea-level change will aff ect large areas of the sub-system. The estuar-
confi rmed that El Niño can have major eff ects on the economy of the
ies in Costa Rica, El Salvador, Honduras and Nicaragua are particularly
region (Carvajal et al. 1997). Poveda & Rojas (1997) reported a signifi cant
vulnerable. The shoreline and the intertidal zone will widen in these
increase in the cases of malaria and other endemic diseases during El
areas. Some countries have estimated the impact of the sea-level rise
Niño events. This is attributed to higher temperatures, which shorten
46
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
the larvae period of mosquitoes, and to a reduction in water fl ow, which
Priority concerns for further
favours the formation of pools and small lagoons where mosquitoes
analysis
breed (Carvajal et al. 1997).
The above assessment of the environmental and socio-economic
Diarrhoea, cholera, hepatitis and other diseases increase their
state of the region identifi ed the priority GIWA concerns based on
geographic distribution and prevalence following natural disasters.
an integrated evaluation of the impacts. The priorities established by
OPS/OMS (1999) noted that following disasters, water-related diseases
the GIWA Task team constitute the basis of the Causal chain analysis
become epidemics. For example, after Hurricane Mitch in 1998 there
which led to the development of policy options which aim to address
were 1 451 cases of cholera in Nicaragua, with a mortality rate of 2.4%.
and mitigate the causes of the environmental and socio-economic
The hurricane severely disrupted the freshwater supply system. An
impacts.
increase in diarrhoea, typhoid fever and other diseases also occurs
when sanitation problems increase during droughts, especially during
The assessment of the major concerns shows that the environmental
El Niño events (WFP/FAO 2002).
quality of the transboundary waters of the Eastern Equatorial Pacifi c
region is deteriorating. This situation is not expected to improve by
Conclusions and future outlook
2020 due to rapid population growth and economic development. The
The IPCC predicts that global climate change will increase rainfall
aquatic concerns are ranked below in priority order.
during the rainy season and prolong drought periods during the dry
season. The reduction of river discharges will increase the size of arid
Southwest Mexico
zones. Coastal cities will experience greater water shortage. Climatic
Pollution was considered by the regional team to be the priority
change will increase the intensity and change the trajectory of storms
concern of the Southwest Mexico sub-system. In 2002, nearly one-
and hurricanes.
quarter of the beaches tested in Mexico failed to meet WHO standards.
SEMARNAT suspects that untreated municipal wastewater is responsible
The governments of the region recognise the potential impact of
for a signifi cant portion of coastal water pollution. Many municipalities
climate changes but actions to limit the vulnerability of their countries
fail to treat, or under-treat, wastewater before discharging it into
to these changes are rarely implemented. They are yet to accurately
Mexico's inland and coastal waters. The tourism boom in Mexico's
assess the impact of climate change on aquatic ecosystems under
coastal regions benefi ts coastal economies while harming coastal
diff erent scenarios. Aquatic productivity is expected to decrease as
ecology. Coastal tourism development is outpacing the development
it does during current El Niño events. Although there is insuffi
cient
of both sewer infrastructure and wastewater treatment. The increase in
information about the potential changes in ocean circulation in the
visitors and associated construction is increasing point and non-point
region, it is known that during El Niño events upwellings collapse when
sources of pollution. In addition to harming bathers, coastal water
the thermocline sinks, resulting in extreme impacts on the productivity
pollution negatively impacts commercial fi sheries, coral reefs, other
of marine ecosystems and the fi sheries.
aquatic ecosystems, the quality of diving, and other forms of tourism.
The problem of beach pollution in Mexico is complicated by the fact
The sectors most aff ected by global change are expected to be agricul-
that there are many sources of pollution, and each of these sources
ture, fi shing and hydroelectric generation. Climate change may increase
is subject to economic, technical and political constraints that will
the prevalence of malaria, which is already experienced during El Niño
determine the eff ectiveness of any particular intervention.
events. According to IPCC projections, the eff ect of El Niño events on
ecosystems, the economy and human well-being will increase in the
Central Equatorial Pacific
future. The severity of the impacts will depend on the level of imple-
Freshwater shortage was selected as the Central Equatorial Pacifi c
mentation of mitigatory programmes, which are still in their infancy.
sub-system's priority concern. Water availability in the sub-system is
strongly infl uenced by climatic variability. The intensity and duration of
El Niño induced droughts and the size of the area aff ected is increasing.
Anthropogenic activities are also aff ecting water availability. The sub-
system has one of the highest deforestation rates in the world which
exacerbates erosion processes in river basins. As a result, rivers carry
large amounts of sediment downstream which is reducing the storage
ASSESSMENT
47
capacity of rivers and lakes, thus modifying stream fl ow and increasing
Pacific Colombian
fl ooding. Population growth and urbanisation are increasing water
Unsustainable exploitation of fi sh and other living resources was
demand beyond sustainable limits. Water availability per capita has
selected as the priority concern of the Pacifi c Colombian sub-system.
reduced by almost 62% since the 1950s. Many of the major urban areas
Despite most of the fi sheries in Colombia being small scale and/or sub-
of the sub-system depend on groundwater supplies which are already
sistence, the current level of exploitation is unsustainable. Although
overexploited. Higher aridity is predicted in the long-term, with the risk
total catches have increased recently, catches of some traditionally tar-
of water shortages becoming severe.
geted species, such as mackerel and sharks, have declined (INVEMAR
2003c, FAO 2004c). The abundance of some coastal shellfi sh such as
Pollution is considered as the second priority concern. Around 95% of
clams, squid and snails has decreased signifi cantly. Similarly, stocks of
municipal wastewaters released into the water bodies of the sub-system
freshwater commercial species are signifi cantly depleted (IIAP 2001b).
are untreated, resulting in microbiological pollution downstream and in
Additionally, the uncontrolled exploitation of marine turtles contin-
coastal marine areas. Agricultural run-off containing agro-chemicals is
ues. As stocks of traditional species become exhausted, fi shing eff ort
degrading freshwater ecosystems and causing eutrophication in coastal
targets other more abundant species to maintain income levels and
waters. Wastewater from industries is also introducing organic matter,
food security. Although the aquatic living resources are unsustainably
suspended solids and nutrients (nitrates and phosphates). The low level
exploited on the coast of the Colombian Pacifi c sub-system, the coast
of sanitation coverage and the widespread use of latrines are leading to
is less populated than some areas of Colombia and therefore the en-
the contamination of aquifers. Pollution is increasing the prevalence of
vironmental problems are mainly localised. It is therefore not too late
diarrhoeic diseases, the main cause of morbidity and infant mortality.
to implement mitigation measures in order to reduce the pressure on
fi sheries resources.
Global change will aff ect the availability of freshwater in the sub-
system. Rainfall is expected to be more intense during the rainy season
Pollution was identifi ed as the second priority concern. Pollution is
and droughts more severe during the dry season. The heavily populated
the principal cause of freshwater shortage in the sub-system. The main
parts of the Pacifi c slope are the most vulnerable to droughts and
sources of pollution are untreated domestic and industrial effl
uents,
changes to river fl ows. However, global climate change is not studied in
hydrocarbon spills and agricultural run-off (Calero et al. 1995, Peña
the Casual chain analysis or Policy options analysis because the causes
1995, IDEAM 2002). However, organic matter and other pollutants car-
are also global issues that can not be resolved through regional action in
ried by water bodies are rapidly dispersed due to the high rate of water
the Eastern Equatorial Pacifi c alone but requires concerted eff orts by the
exchange (Calero et al. 1995, IDEAM 2002). Fees and fi nes have been
international community. The infl uence of future climate change on this
imposed on enterprises and the urban sector in order to reduce the
region is still poorly understood and requires further investigation.
pollution load of water bodies.
48
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Causal chain analysis
This section aims to identify the root causes of the environmental
Based on the results of the assessment (see priority concerns above),
and socio-economic impacts resulting from those issues and
the CCA of the Eastern Equatorial Pacifi c region was conducted for
concerns that were prioritised during the assessment, so that
the priority concerns of each sub-system. The analysis considered the
appropriate policy interventions can be developed and focused
following sub-systems for each priority concern:
where they will yield the greatest benefi ts for the region. In order
Freshwater shortage in the Central Equatorial Pacifi c sub-system
to achieve this aim, the analysis involved a step-by-step process
Pollution in the Central Equatorial Pacifi c and Southwest Mexico
that identifi ed the most important causal links between the
sub-systems
environmental and socio-economic impacts, their immediate
Unsustainable exploitation of fi sh and other living resources in the
causes, the responsible human activities and economic sectors
Pacifi c Colombian sub-system
and, fi nally, the root causes that determine the behaviour of those
sectors. The GIWA Causal chain analysis (CCA) recognises that,
within each region, there is often enormous variation in capacity
and great social, cultural, political and environmental diversity.
Freshwater shortage
The CCA uses a relatively simple and practical analytical model.
For further details of the methodology, please refer to the GIWA
Although the Central Equatorial Pacifi c sub-system has abundant water
methodology chapter.
resources, they are unevenly distributed, with some countries having a
surplus and others having defi cient supplies. In 2002, the discharge of
Socio-economic
Environmental
Concerns
Issue
Immediate causes
Sectors/Activities
Root causes
impacts
impacts
Decreased river
Food insecurity
Forestry
discharges
Demography
Modification of
Increased
Increased erosion and
stream flow
Untreated
Electricity
health risks
sedimentation
wastewater
production
High prevalence of
Freshwater
Pollution of
Economy
water-borne
shortage
Saline intrusion
existing
Agriculture
diseases
supplies
Increased nitrate
Irrigation
Increased cost of
Legal/institutional
concentrations
treatment
Industry
High infant
Deterioration of
Knowledge
mortality
surface water quality
Urbanisation
Overabstraction of
groundwater
Migration
Changes in the
Aquifer depletion
water table
Tourism
Governance
Increased
unemployment
Figure 19 CCA diagram Freshwater shortage in the Central Equatorial Pacifi c sub-system.
CAUSAL CHAIN ANALYSIS
49
the Lempa River shared by El Salvador, Guatemala and Honduras was
Discharge of untreated wastewater
42% below the historic average (SNET 2002). Approximately 70% of the
Freshwater supplies are contaminated in several major basins of Central
total population and 80% of the economic activities are located in areas
America, including the Lempa River and the Grande de Tárcoles River
with a shortage of freshwater. About one-quarter of the population in
basin. According to PNUMA (2001), 95% of the municipal wastewater
the sub-system did not have access to safe freshwater in 2000.
generated in the sub-system enters natural water bodies without
appropriate treatment. El Salvador is particularly aff ected as the
During the Causal chain analysis, the issue of pollution of freshwater
main sources of freshwater, the Lempa River and lakes Ilopango and
supply is emphasised because it is the issue best documented in the
Coatepeque, are highly polluted by wastewater discharges. In the
sub-system. The information regarding the other two issues is somewhat
Lempa River, a two-year study found that 95% of samples contained
limited, not current and tends to focus on specifi c localities and rivers.
E. coli (Levin 2002). Industries, particularly coff ee production, also
discharge large amounts of wastewater without treatment.
Figures 19 and 20 show the causal links between the environmental
and socio-economic impacts of the freshwater and pollution concerns,
Agricultural run-off
the immediate causes, the responsible economic sectors, and the root
The sub-system has one of the largest rates of pesticide consumption
causes that determine the behaviour of these sectors.
in Latin America (2 kg/person), which contribute to the deterioration of
surface and ground water quality. Aquifers in the metropolitan area of
Immediate causes
Alajuela, Cartago and Guanacaste contain increasing concentrations of
Climatic variability
nitrates originating from fertilisers and septic tanks (Reynolds & Fraile
Despite all countries of the Central Equatorial Pacifi c sub-system having
2002). Urban and agricultural run-off are responsible for polluting the
abundant water resources and extracting relatively limited quantities,
Managua aquifer that provides freshwater to 1.2 million people.
some areas experience water scarcity during the dry season when
river fl ows are considerably reduced. During the El Niño, river fl ows are
Root Causes
notably smaller, exacerbating the eff ects of a normal dry season.
Demography
The demographic trends of the last four decades have led to increasing
Land-use changes and practices
demand for freshwater resources for drinking water, agricultural
Deforestation and inappropriate agricultural practices in the catchments
production and industrial processes, among other uses. Urbanisation
have aff ected run-off and river fl ow patterns. These practices have
has intensifi ed and concentrated demand in areas that have limited
increased sedimentation, reducing the capacity of freshwater bodies
freshwater availability. The following demographic trends are driving
including reservoirs, thus increasing the extent and frequency of fl oods.
freshwater shortage issues in the sub-system:
The reduction in water availability has also been attributed to the loss
Over the past 30 years, the population of the sub-system has
of fog forests in the upper sections of the basin. The removal of natural
increased by 98%, from 19.3 million to over 37 million. The
forest cover may also be aff ecting both the recharge rate and water
population density increased over the same period from 39 to
quality of aquifers (Ballesteros 2003).
66 inhabitants/km2. The population of the sub-system will continue
to grow rapidly, reaching 40 million within the next decade.
River diversion and groundwater abstraction
The population is concentrated in specifi c areas. In general, the
River discharges are aff ected by dams, which interrupt the natural
population occupies only a quarter of the sub-system's territory
fl ow of nutrients to coastal waters. Groundwater is the main source
with 70% inhabiting the Pacifi c slope. The urban area is expected
of freshwater in the sub-system and aquifers in most countries are
to increase from 596 km2 to 913 km2 by 2030 if current urbanisation
unsustainably exploited. For example, the aquifers that supply Managua
trends continue.
(Nicaragua), San José (Costa Rica) and San Salvador (El Salvador) are
Urban populations increased by 29% over the period of 1975-2000.
overexploited (Lezama-López 2003). According to the International
About 75% of the population will live in urban areas by 2030 as a
Hydrological Programme of UNESCO, groundwater abstraction in
consequence of natural population growth, longer life expectancy
2010 is expected to be nine times the rate in 1950. Illegal connections
and migration from rural areas. Most rural populations are poor
consume a large proportion of the water available for the cities of the
and migrate for economic reasons, while others are environmental
sub-system. Groundwater use will increase as the quality of surface
refugees fl eeing from natural disasters (OPS/OMS 2001a). The larger
water deteriorates in the future.
urban population will increase further the pressure on water and
50
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
sanitation services. The infl ux of immigrants into urban areas has
water supply is not continuous (between 27% and 98% of the systems),
created an illegal land market and the establishment of illegal
with a supply only available for 6-20 hours/day because of the poor
settlements which have no freshwater supply or sanitation services.
condition of the equipment. This is especially true in rural areas. Almost
40% of water systems have leaks due to the poor maintenance of the
The Lempa River basin is the most densely populated and intensively
network and the use of obsolete technology. In Costa Rica, only 50%
exploited area of the sub-system. Its population was 4.7 million
of the water abstracted is actually charged to users, with the other half
inhabitants in 2001, of which 3.9 million live in the Salvadorian part of
being consumed through illegal connections or wasted as a result of
the basin. The population is expected to double in the next 25 years
dilapidated pipelines (Ballesteros 2003). Illegal connections increase the
(Granados in Llort & Montufar 2003). The majority of economic activity
costs of operation and maintenance, and create an additional problem
and the two major urban centres (San Salvador and Santa Ana) of
in quantifying water losses.
El Salvador are located in the Lempa River Basin. These socio-economic
characteristics are exerting extreme pressure on the freshwater
Economic
resources of the basin.
The assessments by OPS/OMS (2001a) for Latin American and the
Caribbean are also valid for this sub-system. Both reports highlighted
Freshwater supply and sanitation services
the diff ering situations facing the countries, but noted that they share
The current water distribution systems are obsolete and highly
the following economic problems:
ineffi
cient. The countries of the Central Equatorial Pacifi c sub-system lack
Substantial resources are required to improve the current
the economic resources needed to adopt water effi
cient technologies.
infrastructure and to improve the level of freshwater supply
Water supply and sanitation services are subsidised. As a consequence,
coverage.
insuffi
cient revenues are generated to maintain current and invest in
Service charges do not cover operational and maintenance costs.
new technologies, and the population has no incentive to save water.
As a consequence, governments subsidise water supplies.
Most countries in the sub-system depend on foreign imports rather
Diffi
culties estimating operational and maintenance costs as a result
than developing their own technologies that are culturally compatible
of distortions introduced by governmental subsides, and ineffi
cient
and suitable for their local environmental conditions. The Pan-American
management and technical defi ciencies.
Health Organization has stated that technical solutions used to solve
Subsidies do not benefi t the population directly but, instead, hide
water supply problems in rural areas are not always appropriate for
operational and management ineffi
ciencies.
either the local communities or the environment.
The lack of realistic tariff rates and jurisdictional uncertainty
discourages private investment in sanitation and wastewater
The development of both freshwater supply and sanitation coverage is
treatment.
not keeping pace with population growth. The health of the increasing
The privatisation of public services reduces the possibility of
number of people without access to these basic services is at risk. Some
improving the level of wastewater treatment coverage and the
urban areas such as the capitals of most countries in the sub-system (e.g.
introduction of integrated water resources management. In several
Panama, San José, San Salvador, Managua and Tegucigalpa) have grown
cases of privatisation, environmental costs are charged to users and
in a disorganised manner. They are characterised by the occupation
the government assume an intermediary role.
of fringe urban areas by a rural migrating population or by people
Management lacks an enterprise approach.
displaced from neighbouring countries. In these cities, where public
There is a vulnerability to political pressures.
services do not cover even the formal population, urban development
Current statistics show that a high proportion of the population
will increase pressure on the aquifers that are already depleted.
use in situ sanitation solutions, which involve environmental risks.
For example, if latrines are located in porous soils, leachates may
The average freshwater supply coverage in the sub-system was 78%
contaminate aquifers.
in 2000, of which 69% was through the network and 9% through easy
access (OPS/OMS 2001a), which, in most cases, increases human heath
Legal/Institutional
risks. Besides the low level of coverage, several cities in the sub-system
Most countries in the sub-system have a weak legal and institutional
have defi ciencies in treatment processes, forcing the population to
framework for water management which results in overlapping
boil water for direct consumption. Only a small proportion of rural
responsibilities and a duplication of eff ort. There is a lack of control
communities apply chlorine to water for disinfection. In most countries,
and surveillance during the implementation of current regulations
CAUSAL CHAIN ANALYSIS
51
(Dourojeanni 2001). Some regulations, particularly those regarding
prognosis is evidenced by the use of inappropriate farming practices
permissible limits for individual substances or groups of substances,
which result in severe impacts on the water cycle, the lack of treatment
have been modernised. Others are obsolete or incomplete (UNEP/
for industrial and domestic wastes, and the disregard by the public for
GPA 2001) as they do not include provisions for new approaches and
their impact on the environment. Other than the consumptive benefi ts
administration procedures, such as those necessary for a sustainable
of water, there is little recognition or valuation of the indirect benefi ts
development approach. The legislation considers water quantity
water provides through ecosystem goods and services.
separately from water quality. They are also managed by diff erent
institutions, making it diffi
cult to implement a holistic approach at
the institutional level (Escobar 2003). Environmental policies regarding
water management are predominantly sectorial and fail to take into
Pollution
account the multiple uses of water.
Microbiological contamination was considered to be the priority
Most water services in the sub-system are managed by centralised
pollution issue in the Central Equatorial Pacifi c and Southwest Mexico
governmental agencies which lack the capacity to maintain and up-
sub-systems. In the Central Equatorial Pacifi c sub-system, chemical
date the distribution networks and equipment, as well as to monitor
pollution was also considered to be a priority.
the quality of the water supplied. Incipient decentralisation processes
suff er from inadequate governmental support for the transfer
Immediate causes
of responsibilities for water management to local governments.
Discharge of untreated municipal wastewater
Traditionally, local stakeholders were not consulted in the management
The failure to appropriately dispose of excrement and the use of latrines
of water resources. The lack of a multidisciplinary approach leads to
and septic wells in porous soils contribute signifi cantly to the load of
inter-institutional confl icts. There is an absence of an integrated policy
microbiological pollution. The low levels of wastewater treatment
for population distribution, urban development and the provision of
in both sub-systems results in around 95% of wastewater reaching
water services. An integrated river basin management approach to
the Pacifi c Ocean with a high load of organic matter, nutrients and
shared river basins has not been suffi
ciently adopted.
microbial pollutants (PNUMA 2001). Livestock production may also
contribute considerable microbiological pollution to the surface
Knowledge
waters of the Central Equatorial Pacifi c sub-system. High concentrations
Countries in the sub-system lack water monitoring programmes and
of pathogenic micro-organisms associated with water pollution have
environmental, social and economic impact assessment processes.
been recorded in water bodies and on beaches in the Central Equatorial
There is a dearth of knowledge regarding water quality and the eff ect of
Pacifi c and Southwest Mexico sub-system. Many of these beaches are
pollutants on ecosystems and their biota. Most of the countries lack the
important for the tourism industry; the pollution can discourage visitors
economic and technological resources necessary for strengthening the
and cause health problems for bathers.
territorial agencies responsible for undertaking studies on biophysical,
hydro-geological, meteorological and other environmental parameters.
Agricultural run-off
The monitoring of water quality is inadequate as it only focuses on a
Agricultural run-off is the main source of chemical pollution due to
few indicators (Ramírez & Espejel 2001). These knowledge defi ciencies
the large-scale use of pesticides in agriculture, especially for export
are impeding the development of a better management framework
production. High concentrations of pesticides have been found in
that incorporates the particularities of the sub-system's environment.
several coastal sites in water, sediments and biota, posing risks for
The Workshop of Experts on Municipal Liquid Wastes in Latin America,
humans and other living organisms.
held in September 2001 in Mexico (UNEP/GPA 2001), identifi ed the
absence of monitoring and surveillance of water quality as a major
Industrial and mining run-off
obstacle to combating pollution in the region and recommended the
Heavy metals are introduced into water bodies from mining washes
standardisation of water quality criteria (Ballesteros 2003).
and industries. Other chemicals are discharged in small concentrations
within wastewater. Heavy metals, such as lead, copper and chromium,
There is a lack of public awareness of water issues and the associated
have been reported in sediments and surface waters in several
socio-economic impacts, particularly regarding sanitation. There is no
countries in the Central Equatorial Pacifi c sub-system, particularly
culture of water conservation in the population of the sub-system. This
Panama, Nicaragua and Costa Rica.
52
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Root causes
Economy
Population demography and economic development
Low tariff rates for water and underinvestment in sanitation
Today, half of the Central Equatorial Pacifi c sub-system's population is
infrastructure are the principal causes of the lack of basic sanitation
urban and by 2030 the proportion is expected to increase to three-
services in the Central Equatorial Pacifi c sub-system. In Panama, water
quarters. The coverage of sanitation services has not expanded
and sanitation services are subsidised resulting in the authorities
suffi
ciently to cope with the increasing quantities of wastewater
receiving insuffi
cient revenues to invest in the expansion of sanitation
produced by the swelling urban population. The growing population
services. As a consequence, investment was limited to maintenance
and export market requires more food which is leading to the application
during the 1990s. Privatisation of sanitation services has led to the
of more agro-chemicals and, thus, increased chemical pollution.
improvement of waste collection rather than sewage treatment or
water supply. In fact, there is no example of wastewater treatment
The tourism boom in Mexico's coastal regions is benefi ting the
services being privatised. There is a lack of economic incentives to
economy but harming coastal ecology. The growing numbers of visitors
encourage industries to adopt environmentally friendly technologies
and associated development are increasing the volume of point and
and practices. In terms of disincentives, polluters are not taxed
non-point sources of pollution (Rivera-Arriaga & Villalobos 2001) and
appropriately for the environmental damage that their activities cause.
placing additional pressure on sewer infrastructure and wastewater
In the Southwest Mexico sub-system, federal authorities lack the
treatment facilities. The negative environmental impacts of untreated
appropriated mechanisms to collect fi nes from local governments.
wastewater are particularly apparent in and around the coastal tourist
Such fi nes could be used for maintenance or for the construction of
cities of Acapulco, Ensenada, Veracruz, and Xihuatanejo (Ascencio
new wastewater treatment plants.
pers. comm.). In cities such as these, largely uncontrolled coastal
tourism development has put enormous pressure on the ability of the
Legal/Institutional
ecosystems to absorb municipal waste.
All countries in the sub-system are failing resolve their pollution
problems, in part due to fi nancial problems and in part due to the
Technology
unwillingness of governments to regulate economic activities for fear
The major cities in the Central Equatorial Pacifi c have dilapidated
of constraining development. There is a lack of common coastal and
wastewater treatment systems (OPS/OMS 2001a). In Guatemala, only
marine policies with specifi c environmental objectives that address
15 municipalities treat wastewater, and only 4 out of 16 plants in the
pollution issues. This has resulted from an inappropriate institutional
metropolitan zone are functioning (FAO 2004a). Design fl aws have
framework and the application of freshwater criteria to marine
frequently led to new systems failing soon after installation.
environmental legislation. The countries within the sub-system have
diff ering marine policies, except those related to maritime aspects
Industrial processes often involve the use of antiquated technology.
such as traffi
c and national security. Institutional weaknesses and a
Political will to force or encourage industry to adopt cleaner
lack of coordination among the diff erent governmental sectors hinder
technologies is lacking. Industry managers are also uninformed about
the implementation of legislation and environmental management
new technological alternatives and there is a lack of facilities for the
instruments (e.g. environmental impact assessments, management
recycling of industrial wastes. Guidelines on agricultural best practice
plans and environmental auditing). Industries and agriculture are
including techniques to reduce the use of agro-chemicals and to
regulated by a weak and uncoordinated legal framework. In most
improve soil management are not disseminated to farmers.
countries, the institutions responsible for river basin management
only focus on water distribution and consumption, have overlapping
Mexico's water treatment infrastructure is signifi cantly less advanced than
responsibilities and rarely encourage stakeholder participation in the
that of other nations in the Organisation for Economic Cooperation and
decision making process. The control and surveillance of pollution is
Development (OECD), as well as other countries in Latin America. At least
undertaken by a variety of institutions. River basins and the coastal zone
20% of the existing treatment facilities in Mexico are non-operational
are managed autonomously by diff erent institutions (Escobar 2002).
and a signifi cant percentage of those in operation are performing below
their capacity (OECD 2003). While over 76% of the Mexican population
The legal regime and the institutional organisation of several countries
is connected to sewer systems, only 26% is connected to wastewater
in the Central Equatorial Pacifi c sub-system have been characterised
treatment facilities (OECD 2003); the wastewater is therefore discharged
by Jouravlev (2001):
directly into the ocean or inland waterways without treatment.
CAUSAL CHAIN ANALYSIS
53
In Costa Rica, legislation is disarticulate and, in part, obsolete
pollution targets. They have even shutdown the worst off enders. Despite
(Ballesteros 2003). In several cases, laws and decrees are confl icting
these improvements, pollution levels are still high due to a lack of direct
or are not implemented due to a lack of institutional capacity.
control over municipal pollution sources. Under the Mexican Constitution,
In El Salvador, the diversity of laws related to water resources
municipalities are responsible for the maintenance of their water
creates confusion in defi ning responsibilities. In fact, there are
systems and are largely autonomous from state and federal authorities
numerous laws but few that have specifi c regulations needed for
(Constitucion Nacional de Mexico 1992). Therefore, attempts to regulate
implementation. To solve these problems a new Law of Waters is
municipal pollution have been largely ineff ective as the government has
being developed.
little enforcement power to collect fi nes from municipalities who exceed
Guatemala does not have a general water law but secondary laws
federal pollution limits, and no power to directly fi ne those who pump
partially regulate issues related to water, its use and conservation.
their waste into these municipally controlled waters.
In Honduras, until recently, the responsibilities for implementing
regulations regarding water management were dispersed
The Mexican federal government and several international NGOs have
between several institutions. However, important advances in
invested in the construction of sewers and treatment facilities. However,
water management have been achieved, including the creation of
the strong legal provisions guaranteeing municipal autonomy prohibit
the National Council for Sustainable Development (CONADES) and
federal authorities from funding the ongoing maintenance and upkeep
the Secretary of Natural Resources and Environment (SERNA). The
of these investments. This means that in communities with limited
Framework Law of Waters, currently in development, will provide
economic resources, funding of waste treatment services is often a low
a modern, legal, technical and institutional basis for the integrated
priority. These aspects of municipal water control have resulted in the
management of water resources.
breakdown of many recent environmental initiatives. While many state
In Nicaragua, the integrated management of water continues to be
and municipal governments have turned to outside contractors to run
fragmentary and lacking in coordination (MARENA in FAO 2002a).
their wastewater treatment operations (called operating agencies), major
In Panama, institutions in charge of water management do not have
sanitation-related decisions are often made by municipal offi
cers. These
an integrated legal framework. The lack of appropriate technical
decisions are frequently based on political considerations that have little
knowledge and economic constraints impede the implementation
relevance to the long-term water and sanitation needs of a community.
of current regulations.
Many pollution problems impact downstream communities and
In Southwest Mexico, SEMARNAT, Comision Nacional del Agua (CNA)
ecosystems, especially those on the coast. There is insuffi
cient
and other regulatory bodies have achieved increasing success in
investment in upstream sewage infrastructure which could reduce the
controlling large volume industrial polluters whose wastes fl ow into
impact on the economy and public health of many other communities
federal waterways. These agencies have direct jurisdiction over facilities
sharing the same watershed. These problems are exacerbated by the
aff ecting federal waters and are able to enforce fi nes for exceeding
sheer number of municipal governments.
Socio-economic
Environmental
Concerns
Issue
Immediate causes
Sectors/Activities
Root causes
impacts
impacts
Increase of water-
Increased
Agriculture
Economy
borne diseas
concentrations of
Agriculture run-off
microbiological
Microbiological
Increased health
pollutants
Urbanisation
risks particularly to
Untreated
Legal
indigenous people
wastewater
Increased chemical
Increased
Pollution
concentrations
Governance
Chemical
Discharge of
treatment costs
Industry
Increased heavy
animal waste
metal concentrations
Demography
Loss of revenues
in sediments
Chemical release
Mining
Increased risk of
Increased DDT
Technology
Discharge of
poisoning
concentrations
effluents
Decreased
Education/
aesthetic value
knowledge
Release from
mining
Figure 20 Diagram showing the Causal chain analysis of microbiological and chemical pollution in the Central Equatorial Pacifi c and
Central Mexican sub-systems.
54
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Knowledge
Destructive fi shing practices
In the Central Equatorial Pacifi c sub-system, available information is
The use of destructive fi shing gear has resulted in a decline in
dispersed, sparse and not current, which restricts the understanding
recruitment and the degradation of the habitat of some commercial
of the real situation. Limited research and technological development
species. Today, shrimp trawling nets and gillnets are considered the
hinders progress in addressing pollution issues. In the Southwest
main threat to marine turtles in Colombian waters.
Mexico sub-system, local municipal governments lack personnel with
the necessary technical expertise to create and maintain complex
Excessive by-catch and discards
wastewater treatment networks. Additionally, politicians poorly
Although there have been no studies of the level of by-catch in the Pacifi c
understand wastewater and pollution issues and their eff ects on public
Colombian, based on studies in territories within close proximity of the
health and local economies. This often leads to political decisions that
sub-system, it is believed that large quantities of fi sh are caught as by-
do not recognise the environmental and social benefi ts that could be
catch in the shrimp trawling industry and the majority are discarded.
obtained through investments in pollution control.
Root causes
Technology
On the Colombian Pacifi c coast, non-selective and destructive fi shing
Unsustainable exploitation of
gear is employed in the artisanal and industrial fi sheries. Such gear is
fish and other living resources
used to increase short-term profi ts, but at the expense of the long-
term sustainability of fi sh stocks. As the distribution of fi sh species has
The unsustainable exploitation of fi sh and other living resources was
changed and stocks of traditionally exploited species have declined, the
considered to be the priority concern in the Pacifi c Colombian sub-
fi shing industry has began to exploit stocks which are further off shore
system. The Causal chain analysis focuses on the issue of overexploitation
using new technologies.
as it is having the most severe impacts, but also considers destructive
fi shing practices and excessive by-catch and discards.
Economy
Investment in the fi sheries sector is aimed at increasing catches of
Immediate causes
species valuable on the international market; there are few incentives
Excessive fi shing eff ort
to supply local demand.
The current level of fi shing eff ort is unsustainable. According to FAO
(2004c), catches of marine fi sh, crustaceans, molluscs and other marine
Legal/Institutional
living resources decreased in Colombia between 1992 and 2000.
There is a lack of harmonisation between national and international
fi sheries policies. Although Colombia has a legal framework for the
Concern
Issues
Immediate causes
Sectors/Activities
Root causes
Increased effort
Technology
Overexploitation
Shift in population
Fishery
distribution
Unsustainable
Economy
exploitation of fish
Use of non-selective gear
Legal/Institutional
Unsustainable harvest
practices
Knowledge
Habitat and
community
Forestry
modification
Shift in population
distribution
Governance
Decreased habitat
Figure 21 Diagram of the Causal chain analysis of overexploitation in the Pacifi c Colombia sub-system.
CAUSAL CHAIN ANALYSIS
55
management of natural resources, there is a lack of inter-institutional
shown a decreasing trend in the catches of some important species,
coordination, resulting in the weak implementation of existing
the long-term eff ects on fi sh stocks are unknown. The fi sheries are
environmental laws. Domestic and foreign fi shing fl eets are able
irregularly monitored and there is limited surveillance of aquatic
to avoid legislation due to weak enforcement. Limited stakeholder
ecosystems (INVEMAR 2003c). The quantity and impact of by-catch
participation in decision making processes often results in the
and discards produced by the fi shing industry in the sub-system, as
unsuccessful implementation of fi sheries policies.
well as the distribution and infl uence of introduced species, has not
been studied.
Knowledge
There is a lack of detailed information about the exploitation and
status of fi shing resources in Colombia. Although recent data has
56
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Policy options
This section aims to identify feasible policy options that target
Box 1
Immediate actions recommended by the Latin
key components identifi ed in the Causal chain analysis in order
American Workshop on Wastewater Management.
Mexico 10-12th September, 2001.
to minimise future impacts on the transboundary aquatic
1. Technological:
environment. Recommended policy options were identifi ed
· Implement re-use practices; and
through a pragmatic process that evaluated a wide range of
· Optimise water use.
potential policy options proposed by regional experts and
2. Financing
key political actors according to a number of criteria that were
· Establish financial strategies based on regional, national and river basin
priorities;
appropriate for the institutional context, such as political
· Devise self-funding sources; and
and social acceptability, costs and benefi ts, and capacity for
· Rating systems that include subsidies aimed at promoting higher coverage of
water and sanitation services in deprived areas.
implementation. The policy options presented in the report
require additional detailed analysis that is beyond the scope
3. Technical training
· Training to improve supervision, management and assessment capabilities;
of the GIWA and, as a consequence, they are not formal
· Personnel training and institutional strengthening in different geographic areas
recommendations to governments but rather contributions to
of the sub-system; and
· Develop an emergency response capacity in preparation for potential natural
broader policy processes in the region.
hazards.
4. Environmental education/dissemination/awareness-raising
Recommendations made by the GIWA regional experts of the Eastern
· Promote transparency in public information, such as service quality indicators
and environmental quality indicators; and
Equatorial Pacifi c region during the two preparatory meetings coincide
· Encourage the active participation of the media, civil society and the ministries
with those developed by international forums on water management
of education in awareness-raising activities.
(UNEP/GPA 2001) and those recommended in the Environmental Plan
5. Research
of Central America (PARCA). The latter established a set of principles to
· Develop water and sanitation services and environmental quality indicators;
· Formulate regulations for water supply and waste management based on local
strengthen environmental management and harmonise the approaches,
knowledge and stakeholder participation;
policies and management instruments of the member states of Central
· Carry out a Latin American diagnosis of management priorities, taking into
consideration each country's capacity;
America. Box 1 shows the immediate actions recommended by the
· Undertake case studies in tropical and dry areas;
Latin American Workshop on Wastewater Management (2001).
· Promote the adoption of new management instruments; and
· Evaluate the contribution of diffuse pollution in comparison with isolated
pollution.
6. Legislation/rules
· Promote land-use planning as an instrument;
Southwest Mexico
· Up-date the laws on water; and
· Promote the spreading and overlapping of administrative roles with regard to
water as a resource.
Problem definition
7. Other
Pollution has been identifi ed as the priority concern of the Southwest
· Planning (basin-wide); and
Mexico sub-system due to the high levels of microbiological pollution
· Formulation of public policies at the state level which recognise water as a
strategic resource.
recorded in inland and coastal waters and biota. This is attributed to the
POLICY OPTIONS
57
discharge of untreated wastewater in the river basins of the sub-system.
less-conventional municipal wastewater treatment technologies
The tourism industry is being adversely aff ected by polluted beaches
available. Large treatment facilities consume a lot of energy, generate
and the health risks of microbiological pollution.
large quantities of excess sludge that must be disposed of or used, and
require relatively sophisticated equipment that requires highly skilled
Only 26% of Southwest Mexico's population is connected to wastewater
personnel. Alternatively, technologies such as lagoons, treatment
treatment (OECD 2003). The sewage infrastructure that does exist is
wetlands, anaerobic treatment, and reuse schemes are more
commonly non operational, with most wastewater discharged directly
sustainable and cost-eff ective wastewater treatment options. Lagoons
into the ocean or inland waterways without treatment. Coastal tourism
and stabilisation ponds are biological treatment options with low
development is further increasing the pressure on sewer infrastructure.
operational costs (UNEP 2000). Educating municipal decision makers
Regulatory agencies have achieved increasing success in controlling
regarding the various conventional and non-conventional wastewater
large volume industrial polluters whose wastes fl ow into federal
treatment options will enable them to choose the most appropriate
waterways. However, pollution levels are still high due to a lack of direct
facility for their community.
control over municipal pollution sources and weak enforcement power
which prevents the collection of fi nes from municipalities who exceed
Introduce a fee-and-rebate system for municipal wastewater
federal pollution limits. Local municipal governments lack technical
Mexico's current diffi
culties in enforcing fi nes on municipalities are an
expertise and fi nancial capacity to create and maintain wastewater
obstacle to developing a system of rebates and fees. A comprehensive
treatment networks.
study of the feasibility of implementing such a scheme in Mexico
is necessary. Box 2 outlines the methodology of a fee-and-rebate
A variety of options to improve the quality of coastal waters along
system.
Mexico's tourist beaches were considered. The policy options aim to
Box 2 Fee-and-rebate
system
address the root causes of microbiological pollution in the Southwest
In a fee-and-rebate system, the government sets a threshold pollution level for a
Mexico sub-system and are therefore grouped under the various types
municipality or industrial plant. Municipalities receive a rebate for each unit below
the threshold or a fee (replacing the fine) for each unit above the threshold. The
of root cause.
fees can be used to pay for the rebates. In essence, municipalities choosing to
pollute forego the rebate opportunity, and thus face higher costs for polluting.
Annex IV gives further details of the proposed fee-and-rebate system.
Policy options
Technology and economy
Rehabilitate existing, and construct new, wastewater treatment
Demography
facilities
Reduce excess water use
The government of Mexico must recognise wastewater treatment
Consumers tend pay water rates that are far below the true cost of
as a priority issue and allocate greater funds for building new and
water extraction and delivery, and, as a result, tend to overuse water.
maintaining existing wastewater treatment facilities. In many cases,
In addition, urbanisation is tending to increase water use, requiring the
facilities need to be rehabilitated in order to operate at their designed
expansion of wastewater treatment infrastructure (Veenstra et al. 1997).
capacity levels. Investment in sewer systems and wastewater treatment
Several strategies can be employed to reduce water consumption. The
facilities is currently co-funded by federal, state, and local sources.
two main methods are education programmes and a fee-and-rebate
Further funding is often received as loans from various development
system applied to the end-users of water.
banks. Since the federal government does not have the legal power to
earmark funds for specifi c purposes, a simple increase in grant funding
By reducing water consumption, less water drains into the sewage
from the federal level to municipalities is unlikely to leverage funds for
system and is needed to be treated, thus reducing costs and the
the operation and maintenance of treatment facilities. One option
pressure on existing treatment facilities (UNEP 2000). However, the
would be for the Federal government to match investment made by
waste becomes more concentrated as domestic waste production per
local governments in treatment facilities with a grant.
capita remains fairly constant but the concentration of contaminants
varies with the amount of water consumed (Veenstra et al. 1997). The
Local circumstances defi ne the most appropriate technology and
eff ectiveness of this policy option varies according to the local water
implementation strategy. The fi nancial and technical limitations of local
supplier and only applies to municipalities with existing wastewater
communities must be considered so that the facilities can be operated
treatment infrastructure.
and maintained locally. There are a wide variety of conventional and
58
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Knowledge
and guarantee municipal investment in waste treatment infrastructure
Formulate and implement education and information strategies
and operations. These legal reforms fall into two general categories:
Education and information strategies inform the public and government
those designed to make current regulations more eff ective; and those
offi
cials about the problems caused by pollution. Increased technical
designed to increase stakeholder participation in waste management.
assistance is required for municipalities in the development, operation
and maintenance of wastewater treatment infrastructure. The following
While the direct regulation of polluters and municipalities is an
groups could be targeted by education campaigns:
important control instrument, it creates a dynamic in which polluters are
Public offi
cials: Educating public offi
cials about the costs of water
opposed only by federal bureaucrats, not by those harmed by pollution.
pollution allows them to make more informed and eff ective
The victims of pollution can be empowered by being able to take legal
decisions related to the control of water pollution.
action against non-complying industries or municipalities, i.e. to create
The public: The coastal population should be aware of the impact of
a system of class-action civil law suits (Zilberman pers. comm.).
water pollution on the tourism industry, their health and livelihood.
Small businesses: The waste discharged by larger industries has been
reduced considerably in response to Federal initiatives. Smaller
businesses, which discharge pollutants directly into municipal
Central Equatorial Pacific
sewer systems, need to be targeted by education campaigns in
sub-system
order to reduce their contribution.
Definition of the problem Freshwater shortage
Publicly rate municipalities for their level of compliance with
Freshwater shortage was considered as the priority aquatic concern of
wastewater treatment standards
the Central Equatorial Pacifi c sub-system. Although the sub-system has
Decision makers will be more likely to take action to improve wastewater
abundant water resources, they are unevenly distributed and seasonal
management if there is lobbying by the public. Grading municipalities
droughts aff ect extensive areas, especially during El Niño years. The
according to their level of compliance with water pollution standards
discharges of several rivers have reduced (Vörösmarty et al. 1998). The
and publicising this information will engage the public and allow them
high rate of deforestation is increasing erosion and the quantity of
to identify which municipalities are failing to maintain adequate water
suspended sediment in freshwater systems, thus modifying stream fl ow
standards. This will foster competition among municipalities which will
in several areas of the sub-system. Human activities are polluting both
ultimately improve standards. Introducing a public rating system that
surface- and groundwater supplies in many of the sub-system's river
applies to all Mexico's larger municipalities will reduce opposition to the
basins. Because groundwater is the main source of freshwater supply,
current beach pollution rating system. Rating upstream communities
many aquifers are overexploited in the sub-system.
allows coastal municipalities to identify the sources of pollution and
apply political pressure on polluters.
Population growth and urbanisation have led to increasing demand
for freshwater resources and the concentration of demand in areas
Legal/Institutional
that have limited freshwater availability. Because water supply and
Create autonomous water districts
sanitation services are subsidised, insuffi
cient revenues are generated
This policy option involves the creation of independent wastewater
to maintain current and invest in new technologies, and the population
districts consisting of representatives from the relevant municipalities.
has no incentive to save water.
Despite the involvement of municipal governments, the water district
itself should be a separate legal and political entity, with the exclusive
Most countries in the sub-system have a weak and outmoded legal
responsibility of managing water treatment operations. By removing
framework for water management which does not provide for the
decisions regarding water treatment from the normal political
incorporation of new criterion and approaches. Institutions weakly
structures of local municipal governments, federal funding can be
implement current legislation, are vulnerable to political pressures,
targeted at developing treatment infrastructure.
lack trained personnel and have limited budgets. There is a lack of an
integrated river basin approach to water management. Traditionally,
Reform the pollution-related legal framework
local stakeholders were not consulted in the management of water
Some reform of the Mexican legal framework could provide additional
resources. Countries in the sub-system lack water monitoring
power to regulatory agencies to more eff ectively control water pollution
programmes and public awareness of water issues is limited. The
POLICY OPTIONS
59
indirect benefi ts that water provides through ecosystem goods and
the sub-system level. Databases should be created for decision makers
services are rarely valuated.
to access policy relevant and current information so that they can
develop and adopt appropriate policies.
Countries of the region agreed during the Central American Dialogue
about Water, Food and Environmental Sustainability (San Jose, Costa
Develop and implement environmental awareness programmes
Rica, 2001) to adopt specifi c policies related to water management
The public lack an awareness of water issues and the associated socio-
(see Annex III). The policy options developed by the regional team
economic impacts, and there is no culture of water conservation. There
of the Central Equatorial Pacifi c sub-system, presented below, directly
is a need to recognise the value of water for economic development,
address some of the priority root causes identifi ed during the Causal
particularly when formulating development strategies. There is
chain analysis.
insuffi
cient information and guidance regarding available techniques for
reducing water pollution and treating water. By establishing, promoting
Policy options
and implementing environmental awareness training programmes at the
Demographic
regional level this option aims to develop a culture of water conservation.
Integrate territorial planning with water management
Awareness programmes should increase environmental consciousness
Urban planning regulations are not always enforced in the countries
of the importance of a healthy environment and the impact of humans
of the sub-system. Even if they are enforced, these regulations usually
on water resources. This supports the implementation of integrated
concentrate on territorial planning rather than addressing freshwater
management plans. To create a water conservation culture in the long-
shortage issues. This option would support the countries of the sub-
term, formal education programmes should include key environmental
system, using economic and technological instruments, in developing
issues in their curricula, including those related to water.
their own policies, legislation and regulations regarding urban planning,
which integrate territorial issues (i.e. migration, urban sprawl) with water
Governance, legal and institutional
management.
Reorganise the water sector
Most countries in the sub-system have a weak legal and institutional
Promote new development centres in rural areas
framework for water management with overlapping responsibilities and a
Urban water supply services are unable to provide for the increasing
duplication of eff ort. Some regulations are obsolete or incomplete as they
numbers of migrants from rural areas. The promotion of new
omit provisions for new approaches and administration procedures. The
development centres in rural areas, which take into consideration
legislation considers water quantity separately from water quality, and
existing activities, may reduce migration to cities. This can be achieved
river basin and coastal management are not integrated (Escobar 2002).
by decentralising productive activities in order to create employment
and by improving social security in rural areas, particularly medical care,
The water sector needs to be reorganised in the short-term (OPS/
education, appropriated family planning, water supply and other basic
OMS 2001a). The modernisation of the water sector should include
services.
the separation of operational and oversight powers, based on an
appropriate strengthening of the legal and institutional framework.
Knowledge
Several countries in the sub-system have policies and a legal framework
Strengthen and establish further monitoring programmes
for water management; others are in the process of developing them
The sub-system lacks a monitoring system for the control and
and require support. The following options should be considered within
surveillance of water quality. This is important for assessing the extent
an ecosystem-based management approach:
of freshwater shortages and defi ning the current and potential supply
Promote the exchange of successful and unsuccessful experiences
capacity required for urban development. This option would establish
regarding water policies, laws and regulations among the countries
fi nancing mechanisms for governmental institutions to develop
of the sub-system.
programmes that monitor the factors determining land occupancy
Apply common water standards and quality criteria in the countries
and its aff ect on water availability and quality, as well as the impact
sharing an international river basin.
on aquatic ecosystems. The countries of the region need international
The review of national and regional legal frameworks for water
support in order to initiate urban development programmes which
management by a multitude of stakeholders.
include provisions for regulating water quality and availability. Studies
Strengthen the current legal framework based on this review and
are also required to establish the carrying capacity of the ecosystems at
international recommendations, with an aim of improving the
60
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
effi
ciency and eff ectiveness of institutions responsible for water
The intensifi cation of agricultural production to feed the growing
management. The reform of the legal framework is necessary in
population is leading to more agro-chemical pollution. Political will and
order to improve institutional governance in the region.
economic incentives to force or encourage industries and agriculture
Integrate coastal area and river basin management.
to adopt more environmentally friendly technologies/practices are
Implement integrated river basin management to reduce the
lacking. Polluters are not taxed appropriately for the environmental
negative eff ects on freshwater quantity and quality caused by
damage that their activities cause.
various water users in diff erent countries sharing a river basin.
Strengthen the agencies responsible for water management in
Legislation and environmental management instruments are often not
order to improve water use effi
ciency and water quality in the
implemented due to an inappropriate institutional framework and a
long-term.
lack of coordination among the diff erent governmental sectors. River
basin management focuses predominantly on water distribution and
Technology and economy
consumption and stakeholder participation in the decision making
Finance the maintenance and expansion of water services by
process is rarely encouraged. There is a lack of accurate and timely
introducing water rates
information.
Currently, insuffi
cient revenues are received to up-date technologies
because the governments of the sub-system subsidise water supply and
Countries of the sub-system have developed diff erent legal mechanisms
sanitation services. Overuse and waste of water is indirectly promoted
to address pollution problems. Annex III outlines some of the regional
by subsides for water supply services. Privatisation agreements do not
agreements that include provisions for addressing pollution, such as
stipulate that the company purchasing the public service has to strive
the Central American Ecological Summit of 1994 and the Convention
for greater water effi
ciencies, adopt cleaner technology or control leaks
for Cooperation in the Protection and Sustainable Development of the
and other water loses from the distribution network.
Marine and Coastal Environment of the North-East Pacifi c (Antigua
Convention) adopted in Guatemala, 2002 (see Annex III).
The introduction of realistic water rates that refl ect the costs of
maintenance and the expansion of water services will promote the
Policy options
effi
cient use of the sub-system's limited water resources. This will provide
Economy
greater revenues to invest in new appropriated technologies and to
Invest in treatment infrastructure
develop a water monitoring programme. To improve the acceptability
Substantial investment is required to rehabilitate treatment systems
of the increased charges, public awareness of the importance of water
and increase the level of sanitation coverage. The countries of the sub-
conservation needs to be raised. Water users should be charged for
system do not have suffi
cient economic resources to develop such
the costs of environmental remediation and river basin management
facilities. Economic and technological support is required from donors
according to the quantity of water used, the impact of its activities
to rehabilitate existing treatment systems and/or to construct new
on the environment, and the mitigation measures it has adopted to
facilities in the countries of the sub-system.
minimise this impact. Incentive frameworks are required to encourage
the private and public sector to adopt sustainable practices.
Adopt the polluter pays-principle
Polluters are not charged for the environmental costs their activities
Definition of the problem Pollution
cause. Economic sectors are, therefore, given little incentive to
Pollution was considered as the second priority concern of the Central
adopt cleaner technologies or to treat their wastes in order to
Equatorial Pacifi c sub-system. Due to the low level of wastewater
reduce the pollutant loads they contribute. Instead, governments
treatment, pathogenic microorganisms, solid wastes and heavy metals
subsidise wastewater treatment and agro-chemicals resulting in
are present along the coasts and in the water bodies of the entire sub-
limited investment in sanitation and more pesticide contamination,
system (PNUMA 2001). Low tariff rates for water and underinvestment
respectively.
in sanitation infrastructure have resulted in a lack of basic sanitation
services for the rapidly expanding urban population. At least 12 diff erent
This option would identify the sectors responsible for pollution and
diseases have been linked to polluted water in the sub-system (PNUMA
impose load-based charges. The polluter pays-principle can be adopted
2001).
by implementing realistic tariff rates for wastewater discharges. The
principle should be developed based on environmental goals and
POLICY OPTIONS
61
objectives agreed upon by multiple stakeholders.
increase the environmental awareness of the population about the
importance of waste management. Environmental issues should be
Legal/institutional
included in formal education curricula.
Review and reform national and regional legal frameworks
There are weak, and in some cases obsolete, legal frameworks and
Strengthen information management
a lack of coordination between the diff erent sectors and institutions
Information about water quality is dispersed, not up-to-date and
responsible for environmental management, many of which have
used within specifi c sectors, thus impeding a holistic understanding
overlapping mandates. International best practice is not considered
of the overall status of water resources. This option proposes the
in national regulations, nor are new approaches related to the use of
improvement of information exchange mechanisms in the sub-system
water. There is little or no coordination between river basin and coastal-
by strengthening and updating the Regional Network for Resources
marine institutions, limiting the possibility of integrated river basin and
Monitoring and other initiatives related to water management and
coastal area management.
surveillance in the sub-system. The countries need to cooperate and
share data regarding the water regime of the sub-system. To support
This option proposes the review of national and international legal
the implementation of the Plan of Action for the Protection of the
frameworks for water management in order to reform institutional
Marine and Coastal Environment of the North East Pacifi c, there needs
frameworks at the national level. Based on this review, a regional legal
to be monitoring and surveillance of pollution from land-based sources.
framework should be developed to apply in each country according
The knowledge base would be improved by monitoring the pollution
to their particularities, and water quality regulations should be
load of coastal waters.
standardised. National regulations should be based on those inspired
by the Antigua Convention (2002).
Strengthen the capacity of the agencies responsible for water
Pacific Colombian sub-system
management
Existing regulations are ineff ectively implemented and enforced.
Definition of the problem
Management instruments and institutional capacity are insuffi
ciently
During the environmental and socio-economic impact assessment
evaluated using, for example, environmental impact assessments and
of the Pacifi c Colombian sub-system, it was established that the
environmental management programmes. Institutional weaknesses,
unsustainable exploitation of fi sh and other living resources was the
the failure to implement legislation and limited monitoring are the
principal concern. Despite most of the fi sheries in Colombia being
main root causes of pollution in the sub-system. Therefore, institutional
small scale and/or subsistence, the current level of exploitation is
strengthening is a priority issue at the regional level.
unsustainable; catches of some traditionally targeted species have
declined (INVEMAR 2003c, FAO 2004c). Stocks of freshwater commercial
This option proposes strengthening the agencies responsible for
species are also signifi cantly depleted (IIAP 2001b).
water management by creating mechanisms and opportunities for
institutional cooperation in order to adopt a holistic approach to water
On the Pacifi c Colombian coast, non-selective and destructive fi shing
management, in which the particularities of both coastal and marine
gear is used to increase short-term profi ts at the detriment of fi sh stocks
areas are considered. The strengthened capacity of the institutions
and marine ecosystems. As the distribution of fi sh species has changed
will allow them to implement programmes aimed at controlling and
and stocks of traditionally exploited species have declined, the fi shing
monitoring pollution in coastal and marine areas. In particular, the
fl eet has began to exploit stocks which are further off shore using new
Network of National Institutions should be established, and coordinated
technologies. The fi sheries sector concentrates on certain valuable
by the Central American Commission for Maritime Transportation in
species to supply the export rather than domestic fi sh market. Existing
collaboration with UNEP.
laws related to the fi sheries are weakly enforced allowing domestic and
foreign fi shing fl eets to avoid legislation. There is lack of institutional
Knowledge
cooperation, fi sheries statistics and stakeholder participation to aid and
Develop and implement environmental awareness programmes
improve the eff ectiveness of decision making processes.
This option would establish, promote and implement environmental
training programmes at the regional level. Educational programmes
Colombia has developed several programmes aimed at addressing
62
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
the environmental problems aff ecting its Pacifi c coast, such as Pacifi c
This option would initiate ethno-education focused towards sustainable
Agenda 21 and the Project Biopacífi co. The policy options proposed
development and the rational exploitation of living resources (clean
in this document should be considered as complementary actions to
production and eco-effi
ciency). Education should be directed at local
those recommended in these initiatives. In a broader scope, Colombia
communities rather than productive sectors since the current legal
has signed several protocols and agreements with other countries of
framework regulates the activities of the latter.
the South East Pacifi c to address transboundary pollution problems,
notably the Convention for the Protection of the Marine Environment
Governance
and Coastal Areas in the South East Pacifi c, and the Plan of Action for the
Further implement integrated coastal zone management (ICZM)
Protection of the Marine Environment and Coastal Areas of the South
Coordinate institutional systems by adopting integrated coastal zone
Pacifi c, which are briefl y described in Annex III. The Policy options
management. Colombia has made signifi cant progress regarding this
analysis focuses on mitigating the root causes identifi ed in the CCA,
approach including the establishment of the Integrated Management
including technology, knowledge, economic and governance drivers.
Unit of Guapi Iscuande. Local authorities need to be monitored by
regional and national agencies to ensure governmental fi sheries
Policy options
strategies are implemented. In parallel to this, the capacity of local
Technology
authorities needs strengthening regarding the management of fi sheries
Transfer of sustainable technologies
resources.
The fi sheries industry in the sub-system has poor access to modern
technologies. The transfer of sustainable technologies can be
Strengthen the self-regulation of coastal communities
accomplished through cooperation among national agencies and
Strengthen the self-regulation processes of coastal communities
between municipalities and other regional and local administration
so that they receive greater responsibilities which are currently
institutions.
exclusive to the government. For this purpose, responsibilities must
be assigned independently of the current political-administrative
Knowledge
framework, as geographic boundaries of coastal communities often
Enhanced information management and education programmes
do not correspond with political boundaries. It is expected that self-
There is a need to widely disseminate key, policy relevant scientifi c
regulation will lead to the increased participation of local communities,
fi ndings to individuals and institutions responsible for fi sheries
especially those of Afro-Colombian and indigenous origin, in decision
management. This requires the active participation of, and cooperation
making and implementation. This will legitimise their administrative
between, the scientifi c community and local stakeholders. Education
structures. This proposal follows the results obtained by Ostrom (2000)
campaigns and training courses for local authorities can improve their
and is in accordance with the community participation mechanisms
understanding of scientifi c fi ndings. Local authorities need access to
stipulated in the National Constitution. The option may prove diffi
cult
up-to-date fi sheries statistics.
to implement as local leaders may be unwilling to participate in the
process and there may be resistance to change by the authorities.
Training courses for community and fi shing association leaders may
Fishing associations should also be strengthened so the interests of
improve the adoption rate of sustainable fi shing practices. They are
the industry are considered.
often responsible for the implementation and oversight of appropriated
practices and have the power to change the behaviour of fi shers. Since
education is the responsibility of the government, this approach
requires the strengthening of the formal education sector so that it
considers environmental issues, including those related to the fi sheries.
POLICY OPTIONS
63
Conclusions and recommendations
Southwest Mexico
Long-term recommendations
Create autonomous water districts; and
Pollution was considered to be the priority concern by the regional team.
Reform the pollution-related legal framework.
Microbiological pollution was found to have the most severe impacts due
to its aff ect on the tourism industry and the health of the population.
In conclusion, pollution abatement is a major challenge for Southwest
Untreated wastewaters from inland and coastal sources enter coastal
Mexico. Increased understanding among public and policy makers of
waters where they degrade marine ecosystems, thus aff ecting tourism
the causes and eff ects of pollution, the establishment of communication
and the commercial fi sheries. Some of the sub-system's important tourism
networks among the stakeholders of a river basin, the creation of
beaches are the most polluted in Mexico resulting in the dissuasion of
incentives as well as penalties for polluters, and greater civil legal powers
tourists. The contamination of surface- and groundwater has reduced the
will shift the political situation in favour of environmental protection. A
availability of freshwater for human consumption. Diseases associated
healthy environment will improve the well-being of the sub-system's
with microbiological pollution are highly prevalent in the sub-system.
population.
Sewer and treatment infrastructure, which is commonly dilapidated,
Areas for further study
has been unable to cope with the increasing quantities of wastewater
There is a general lack of information and data regarding wastewater
produced by the booming coastal tourism industry and rapidly
management and the transboundary eff ects of water-related pollution
growing population. While regulatory agencies have made progress
in the coastal zone. This is presenting a signifi cant obstacle to selecting
in controlling large volume industrial polluters whose wastes fl ow
and implementing appropriate policies. The following studies are
into federal waterways, they do not have the jurisdictional power to
recommended:
control municipal pollution sources. Technical and fi nancial defi ciencies
Initiate studies to quantify the economic impact of coastal water
often prevent local municipalities from developing and maintaining
pollution; and
wastewater treatment networks.
Conduct a survey of local public offi
cials regarding their attitudes to
pollution control.
Recommendations
Near-term recommendations:
Formulate and implement education and information strategies;
Publicly rate municipalities for their level of compliance with
Central Equatorial Pacific
wastewater treatment standards; and
sub-system
Rehabilitate existing, and construct new, wastewater treatment
facilities.
The countries of the sub-system are inextricably linked by hydrological
processes. Water is a vector transporting not only a wide variety of
Medium-term recommendations
valuable resources but also problems from one country to another. For
Introduce a fee-and-rebate system for municipal wastewater.
example, deforestation in Nicaragua is aff ecting aquatic ecosystems in
64
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Honduras, Guatemala and Costa Rica due to increased rates of erosion
of regional instruments of cooperation such as the Plan of Action for
resulting in sedimentation downstream and in coastal areas.
the Protection of the Marine Environment and Coastal Areas of the
North East Pacifi c. The institutions responsible for the management of
Freshwater shortage and pollution were considered to be the most
water and the control of pollution were found to lack administrative and
severe transboundary aquatic concerns in the Central Equatorial Pacifi c
organisational capacity. The selected policy options, therefore, address
sub-system. Both concerns are interlinked as the discharge of untreated
these institutional inadequacies as a prerequisite.
wastewater is contaminating surface- and groundwater, thus reducing
the availability of water suitable for human uses. At the same time,
In the case of freshwater shortage, the following policy options are
population growth and economic development have led to increasing
recommended:
demand for water resources. Water availability per capita has declined
Develop and implement environmental awareness programmes;
by almost two-thirds between the 1950s and 1990s.
and
Reorganise the water sector.
With the exception of Panama City, the other capitals and large cities
depend primarily on groundwater supplies. In Managua, San José,
In the case of pollution, the following policy option is recommended:
San Salvador and the valleys of Choluteca and Tegucigalpa the level
Develop and implement environmental awareness programmes.
of groundwater abstraction is exceeding the natural recharge rate of
the aquifers. Water supply infrastructure is not satisfying demand and
is beset with operational and maintenance failures. Because water
supply and sanitation services are subsidised, insuffi
cient revenues are
Pacific Colombian sub-system
generated to maintain current and invest in new technologies, and the
population has no incentive to save water.
Unsustainable exploitation of fi sh and other living resources was
selected as the priority concern of the Pacifi c Colombian sub-system.
These human dimensions to water availability are set against a backdrop
The current level of exploitation is unsustainable; stocks of some
of variable climatic conditions throughout the sub-system, with some
traditionally targeted species and coastal shellfi sh have been depleted.
parts of the region suff ering from intense periods of drought with a
Freshwater commercial species are also less abundant today. The fi shing
marked reduction in river fl ow. The intensity of rainy periods and the
industry tends to target a limited number of species which are valuable
severity of droughts are expected to increase in the future. Water scarcity
on the international market. Despite stocks of these species becoming
will depress the agriculture sector, the cornerstone of the sub-system's
exhausted, total catches have been maintained or even increased as
economy, increasing unemployment and migration, and causing food
fi shermen are targeting more abundant species in order to sustain their
insecurity. Tourism, an increasingly important industry, will also be
income levels and food security. This has been achieved by the use of
severely impacted by water shortages.
new technologies which allow fi shermen to exploit stocks which are
further off shore in deeper water. They are also using non-selective and
Municipal wastewater is the major source of pollution in the sub-system;
destructive fi shing gear to increase short-term profi ts at the detriment of
95% is discharged without treatment. Only 60% of the population has
fi sh stocks and marine ecosystems. It is weak enforcement rather than a
access to sanitation services, which are frequently latrines. ADD and
lack of laws and regulations that is allowing domestic and foreign fi shing
other water-related diseases are the main cause of the high rates of
fl eets to operate illegally. The various institutions responsible for fi sheries
morbidity and mortality in the sub-system.
management inadequately cooperate and fail to involve stakeholders
in the decision making process. The lack of fi sheries statistics prevents
The root causes of this situation include defi cient environmental policies,
managers from having an accurate understanding of the state of the
institutional failures, biased sectorial approaches, resistance to change,
fi sheries.
the use of obsolete technology, outmoded regulations, and the lack of
inter-institutional integration and stakeholder consultative processes.
Colombia has developed several programmes aimed at addressing
the environmental problems aff ecting its Pacifi c coast, such as Pacifi c
Recommendations
Agenda 21 and the Project Biopacífi co. The policy options proposed in
In order to address pollution in the coastal areas of the Central
this report should be considered as complementary actions to those
Equatorial Pacifi c sub-system, a fi rst step would be the implementation
recommended in these initiatives.
CONCLUSIONS AND RECOMMENDATIONS
65
Recommendations
The analysis of the policy options established that under current
conditions of environmental management and governance the most
feasible option for implementation is:
Enhanced information management and education programmes.
Following the implementation of the above option, which would result
in direct benefi ts for the management of natural resources, it is also
recommended to implement the option:
Strengthen the self-regulation of coastal communities.
66
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
References
Acurio, G., Rossin, A., Texeira. P.A and Zapata, F. (1997). Diagnostico de la
Ballesteros, M. (2003). Diagnóstico de Aguas de Costa Rica, Documento
situación de manejo de residuos sólidos municipales en América
para el Plan de Acción para la gestión integrada de los recurso
Latina y el Caribe, Banco Interamericano de Desarrollo BID. Pub.
hídricos de Centroamérica, San José, Costa Rica.
BID/OPS, No. ENV, 97-107.
Botello, A.V., Villanueva, S.F., Diaz, G.G. and Escobar-Briones, E. (1998).
Alvarado, H. and Gutiérrez, F. (2002). Especies hidrobiológicas
Polycyclic aromatic hydrocarbons in sediments from Salina Cruz
introducidas y trasplantadas, y su distribución en Colombia.
Harbour and Coastal Areas, Oaxaca, Mexico. Marine Pollution
Ministerio del Medio Ambiente-RAMSAR-Corporación Autónoma
Bulletin 36(7):554-558.
Regional del Valle del Cauca. Bogotá, Colombia.
Calero, L., Marrugo, E. and Casanova, R. (1996). La contaminación marina
Álvarez, L. and Manelia, J.A. (1996). Informe Nacional sobre el estado
en el Pacífi co colombiano bajo el enfoque social y económico.
de la contaminación marina en el Pacífi co de Panamá, Comisión
Centro de Control de Contaminación del Pacífi co, CCCP, Dirección
Nacional de Medio Ambiente de Panamá CONAMA, documento
General Marítima, DIMAR. Boletin Cientifi co 5:98-120.
de la Reunión CPPS/PNUMA de Expertos del Pacífi co Sudeste para
Cantera, J.R. and Arnaud, P.M. (1995). Structure et distribution des
revisar el desarrollo de CONPACSE y el estado de la contaminación
associations d'arbres de mangrove de deux baies de la cote
narina en el Pacífi co Sudeste, Guayaquil, Ecuador.
Pacifi que de Colombie: Málaga et Buenaventura. p 245-290 In:
Álvarez, L., Dutary, A. and Palacios, J. (1989). Evaluación de pesticidas y
Restrepo, J.D. and Cantera, J.R. (eds.). Delta del Río San Juan Bahías
metales pesados en biota marina, sedimentos y agua del Pacífi co
de Málaga y Buenaventura Pacífi co Colombiano. COLCIENCIAS/Eafi t
de Panamá, CONAMA. En: Informe de Reunión CPPS/PNUMA de
/Universidad del Valle, Cali, Colombia.
expertos para revisar el desarrollo del CONPACSE y el estado de la
Carvajal E.Y., Jiménez E.H. and Materón, M.H. (1997). Incidencia del
contaminación marina del Pacífi co Sudeste. Guayaquil, Ecuador.
fenómeno del Niño en la Hidroclimatología del Valle del Río Cauca
Améndola, R., Castillo E. and Martínez, P.A (2005). México Part II. In
Colombia. Facultad de Ingeniería. Universidad del Valle, Colombia.
Country Pasture/forage resources profi les. Retrieved April, 2006
Retrieved May, 2004, from: http://www.unesco.org.uy/phi/libros/
from http://www.fao.org/AG/AGP/AGPC/doc/Counprof/Mexico/
enso/carvajal.html
Mexico2.htm.
Castro, E. Jiménez, L. and Leon, S. (2000). Valoración económica-
ANAM (1994). Primera Comunicación Nacional sobre el Cambio
ecológica de la degradación de las aguas que desembocan en el
Climático en Panamá. Autoridad Nacional del Ambiente de Panamá,
Golfo de Nicoya. Universidad Nacional, Costa Rica.
Panamá City Panamá.
Castro, G. (2003). El manejo de la Cuenca del Canal de Panama (CCP),
Artiga, R. (2002). Limites y potencialidades para la gestion integrada de
Una evaluacion de sus necesidades y posibilidades en un proceso
los recursos hidricos de cuencas transfronterizas de Centroamerica.
GIRH, Universidad de Panama- Programna de Grado de Estudios
Estudio de Caso: Gestion de la cuenca compartida del Rio Lempa
en Manejo Medioambiental-Ciudad del Saber. Departamento de
(Guatemala, El Salvador, Honduras, Plan Trifi nio) y su replicabilidad
Sociologia, Universidad de Panama. Retrieved May, 2004 from: http:
Fundacion del Servicio Exterior para la Paz y la Democracia
// www.ciudaddelsaber.org.pa
Fundepam. San Salvador, El Salvador.
Castro, L., Navarrete, A., Cardona, T. Tejada, C., Otero, L., Afanador,
F., Mogollón, A. and Pedroza, W. (2003). Panorama de la
REFERENCES
67
contaminación marina del Pacífi co colombiano. Centro de Control
Coral Reef Alliance. (2003). Watersheds and Healthy Reefs: Making the
de Contaminación del Pacífi co colombiano. DIMAR. Serie de
Connection. The Coral Reef Alliance, San Francisco, United States.
publicaciones especiales Vol 3, San Andrés de Tumaco.
Cortés, R., Muñoz, L. and Sotomayor, O. (1993). Envenenamiento
CCAD (2002). Centro América en la Cumbre Mundia l de Desarrollo
paralítico por mariscos (psp), causado por el dinofl agelado
Sostenible. Comisión Centroamericana de Ambiente y Desarrollo,
Pyrodinium bahamense var. compressum en la costa suroeste de
San José, Costa Rica.
México. Anales del Instituto de Ciencias del Mar y Limnología,
CCAD/IUCN (1999a). Diagnostico del estado de los recursos naturales,
Universidad Nacional Autónoma de Mexico 20(1):43-54.
socioeconómicos e institucional de la zona costera del Golfo
CPPS (2000). Escobar, J.J. (ed.). Estado del Medio Ambiente Marino y
de Fonseca. Doc: Informe del Proyecto Regional Conservación
Costero del Pacífi co Sudeste. Plan de Acción para la Protección
de los Ecosistemas Costeros del Golfo PROGOLFO. Comisión
del Medio Marino y Áreas Costeras del Pacífi co Sudeste. Comision
Centroamericana de Ambiente y Desarrollo/The World
Permanente del Pacifi co Sur, Quito, Ecuador.
Conservation Union. San José, Costa Rica, Morovia Costa Rica,
CPPS (2001). Hidrocarburantes: La Contaminación Marina Regional
Gland, Switzerland.
por Actividades Petroleras. Comisión Permanente del Pacífi co
CCAD/IUCN (1999b). Clasifi cacion Digital de Imagenes de Satelite
Sur. Retrieved April 2004 from: http://www.cpps-int.org/spanish/
del Area de Progolfo, Proyecto Conservación de los Ecosistemas
planaccion/hidrocarb.pdf
Costeros del Golfo de Fonseca. CATIE Laboratorio de Sistemas de
CPPS (2004). Borrador del informe de la 2da Reunión de Expertos
Información Geográfi ca, Turrialba, Costa Rica.
del Grupo Subregional GIWA 65: Análisis de la Cadena Causal
CCCP (2003). Programa de Investigación sobre el Fenómeno El Niño.
y Opciones de Política para los problemas prioritarios, Bogotá,
Centro de Control de Contaminación del Pacífi co, Nariño, Colombia.
Colombia. Comisión Permanente del Pacífi co Sur, Guayaquil,
Retrieved April, 2004, from: www.cccp.org.co
Ecuador.
CCO (2002). Lineamientos De La Politica Nacional Del Oceano Y Los
Croom, M., Wolotira, R. and Henwood, W. (1995). Northeast Pacifi c.
Espacios Costeros- LPNOEC. Comisión Colombiana del Océano,
p 55-106 In: Kelleher, G., Bleakley, C. and Well, S. (eds.). A Global
Bogota, Colombia.
Representative System of Marine Protected Areas, Volume IV. Great
Cedeño, C.V. (1995). Informe del Estado del Medio Ambiente Marino-
Barrier Reef Marine Park Authority/The World Bank/The World
Costero del Pacífi co de Nicaragua, Informe de Consultoría a la
Conservation Union. Washington D.C., United States.
Comisión Permanente del Pacífi co Sur, CPPS, Managua, Nicaragua.
DANE (2001). Cuentas regionales. PIB por actividad económica a
CPPS, Lima Perú .
nivel departamental. Departamento Administrativo Nacional de
CNA (2002). Compendio Basico del Agua en Mexico. Plan Nacional de
Estadísticas, Bogotá, Colombia.
Desarrollo/Comision Nacional del Agua/SEMARNAT, Mexico.
DANE (2002). Departamento Administrativo Nacional de Estadística,
CONAZA (1994). Plan de Acción para combatir la desertifi cación en
Bogota, Colombia. Retrieved April, 2004 from: http://
México. Comisión Nacional de zonas Áridas, Secretaría de Desarrollo
www.dane.gov.co
Social, México.
Díaz, C. J and Fernández, L.M. (1994): Situación Ambiental del Litoral
Consejo Nacional de Rectores/Defensoría de los Habitantes/Programa
Pacífi co de Costa Rica. Informe de Consultoría a la Comisión
de las Naciones Unidas para el Desarrollo. Retrieved April, 2004
Permanente del Pacífi co Sur, San José Costa Rica.
from: http://www.estadonacion.or.cr/info2002/nacion8/Po-
Dourojeanni, A. (2001). Water management at the river basin level:
armonia/Agua%20transparente%20deuda%20invisible.pdf
Challenges in Latin America. Report LC/L.1583-P. Serie Recursos
Conservación Internacional (2002). Colombia, Serie Pacífi co: Ambiente
Naturales e Infraestructura No. 29.
y culturas amenazadas. Retrieved April, 2004 from: http://
El País (2004). Tasa retributiva enreda a empresas de servicios. Retrieved
premioreportaje.org/index.php?pageId=sub&lang=en_US&curre
April, 2004 from: http://elpais-cali.terra.com.co/paisonline/notas/
ntItem=article&docId=740&c=Colombia&cRef=Colombia&year=
Marzo042003/C34N1.html
2003&date=October%202002
EPA (1983).Cabelli, V.J. Health eff ects criteria for marine recreational
Constitucion Nacional de Mexico (1992). Ley De Aguas Nacionales D.O.F.
waters. EPA-600/1-80-031, United States Environmental Protection
01-Xii-, Mexico
Agency. Research Triangle Park Foundation, United States.
Contreras, F. Castañeda, O., García-Nagaya, A. and Gutiérrez, F. (1995).
EPA (2005). Procedures for derivation of equilibrium partitioning
Nutrientes en 39 lagunas costeras mexicanas. Retrieved February,
sediment benchmarks for the protection of benthic organisms:
2005 from: http://rbt.ots.ac.cr/revistas/44-2/contr.htm
Metal mixtures (cadmium. copper, lead, nickel, silver and zinc).
68
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
EPA-600-R-02-011. United States Environmental Protection
FAO (2002b). Datos de captura de peces marinos y pesca de aguas
Agency Offi
ce of Research and Development, Washington D.C.
continentales FISHBASE. Retrieved March 2004 from: http://
United States.
www.fao.org
Escobar, J.J. (1996). Políticas, estrategias y acciones para la conservación
FAO (2003). Resumen informativo sobre la pesca por países: La república
de la diversidad biológica en los sistemas costero- marinos de las
de Colombia. Retrieved February 2004 from: http://www.fao.org/
áreas protegidas. Documento Técnico No 22, FP/0132-94-1. Proyecto
fi /fcp/es/COL/body.htm
FAO Ofi cina Regional para América Latina y el Caribe/ Programa
FAO (2004a). Perfi les Nacionales del Uso del Agua en la Agricultura.
de las Naciones Unidas para el Medio Ambiente. Conservación de
Ofi cina Regional de la FAO AQUASTAT. Retrieved March, 2004
la Diversidad Biológica en Áreas Silvestres y Áreas Protegidas de
from: http://www.fao.org
América Latina y el Caribe, Santiago, Chile.
FAO (2004b). Global capture and aquaculture databases updated to
Escobar, J.J. (2000). Estado del medio ambiente marino y costero del
2002. Retrieved May, 2004 from: http://www.fao.org
Pacífi co Sudeste- Plan de Acción para la Protección del Medio
FAO (2004c). Capture production: by major fi shing areas. Fisheries
Marino y Áreas Costeras del P/SE, pub. Comisión Permanente del
Department. Retrieved May, 2004 from: http://www.fao.org
Pacífi co Sur, Secretaria General, Quito, Ecuador.
FDA (1993). Fish and Fishery Products Hazards and Controls Guidance.
Escobar, J.J. (2001). Evaluación sobre las fuentes terrestres y actividades
Food and Drug Administration, Center for Food Safety and Applied
que afectan al medio marino, costero y de aguas dulces en la región
Nutrition, Offi
ce of Seafood, Washington D.C., United States.
del Pacífi co Nordeste. 3/Inf/2. UNEP/DEC/NEP/EM.
Franco, A. (2001). Informe Nacional de Panamá: Evaluación de fuentes
Escobar, J.J. (2002). Sostenibilidad de recursos pesqueros, cultivos
terrestres y actividades que afectan al medio marino, costero y
ilícitos, metropolizacion y contaminación de aguas en Colombia.
dulceacuícola de la República de Panamá en el Océano Pacífi co
In: Síndromes de Sostenibilidad Ambiental en América Latina y el
Nordeste. Programa de Naciones Unidas para el Medio Ambiente/
Caribe. Informe de Consultaría para la Comisión Económica para
Global Programme of Action for the Protection of the Marine
América Latina y el Caribe. Unidad de Medio Ambiente y Desarrollo,
Environment from Land-based Activities/Autoridad Marítima de
Santiago, Chile. (Unpublished)
Panamá, Panamá.
Escobar, J.J. (2003). Perfi l de la capacidad de respuesta de la región
Gamez, L. (2002). Octavo Informe sobre el Estado de la Nación en
del Pacifi co Nororiental a la contaminación por petróleo a 2003.
desarrollo humano sostenible.
Documento Informe de consultaría a COCATRAM para la IIa Reunión
Garay, J.A., Marín, B. and Vélez, A.M. (2002). Contaminación marino-
Intergubernamental del Plan de Acción para la Protección y el
costera en Colombia. p 101-130 In: Ospina-Salazar, G.H. and Acero,
Desarrollo Sostenible del Medio Marino y Zona Costera del Pacifi co
A. (eds.). Informe del Estado de los Ambientes Marinos y Costeros
Nororiental, Managua, Nicaragua. Retrieved April, 2004 from: http:
en Colombia: Año 2001. Serie de Publicaciones No. 8. Instituto de
//www.cocatram.org.ni
Investigaciones Marinas y Costeras, Colombia.
Escobar, J.J. (2005). Evaluación a 2005 sobre las fuentes terrestres
García, J.E. (1998). Intoxicaciones agudas con plaguicidas: Costos
y actividades que afectan l medio marino, costero y de aguas
humanos y económicos. Revista Panamericana de Salud Pública/
dulces asociadas en la región del Pacífi co Nordeste (NEP). Informe
Pan American Journal of Public Health 4(6):383-387.
Regional. COCATRAM/PNE/IG.3/Informativo 10. III Reunión
Girot, P. and Jiménez, A. (2003). Marco regional de adaptación al cambio
Intergubernamental del Plan de Acción. Ciudad de Guatemala,
climático para los recursos hídricos de Centro America. The World
Guatemala.
Conservation Union, Morovia, San José Costa Rica.
Espinoza, A. (2002). Evolución de la industria mexicana de fertilizantes
Glynn, P.W. and Wellington, G.M. (1983). Corals and corals reef of the
en la agricultura. Secretaría de Agricultura, Ganadería, Desarrollo
Galápagos Islands. University of Berkeley Press, United States.
Rural, Pesca y Alimentación. Retrieved February, 2005 from: http:
González, J. (2002). El virus de la mancha blanca un efecto de la
//www.sagarpa.gob.mx/Cicoplafest/evol_ind.htm
vulnerabilidad de la camaronicultura de la región de América Latina
FAO (1997). Review of the state of world marine fi sheries. Marine
y el Caribe. Retrieved February, 2005 from http://www.fao.org/
Resources Service. Fisheries Resources Division. Fisheries
Regional/LAmerica/prior/recnat/recursos/pesca/virus.htm
Department. FAO Fisheries Circular No. 920, FIRM/C920. Food and
Hancock, L.E. and Gilmore, M.S. (2004). Pathogenicity of Enterococci.
Agriculture Organization of the United Nations, Rome, Italy.
Retrieved February, 2000 from: http://www.enterococcus.ouhsc
FAO (2002a). Uso de pesticidas. FAOSTAT. Retrieved March, 2004 from:
.edu/
http//www.fao.org
REFERENCES
69
Heckadon-Moreno, S., Ibañez, R.D. and Condit, R. (1999). La Cuenca del
conservación de las aguas marinas y costeras. Diagnostico Nacional
Canal: Deforestación, Contaminación y Urbanización. Instituto de
2003. Instituto de Investigaciones Marinas y Costeras, Colombia.
Investigaciones Tropicales. Panamá.
INVEMAR (2003c). Informe del Estado de los Ambientes Marinos y
IDEAM (2001). El Agua. p 114-189 In: El medio ambiente en Colombia.
Costeros en Colombia: AÑO 2002. Servifráfi cas, Medellín. Serie de
Instituto de Hidrología, Meteorología y Estudios Ambientales de
publicaciones periódicas No. 8. Instituto de Investigaciones Marinas
Colombia. Retrieved from: http://www.ideam.gov.co/publica/
y Costeras, Colombia.
medioamb/cap4.pdf
IPCC (2001). Houghton, J.T., Ding, Y., Griggs, D.J., Noguer, M., van del
IDEAM (2002). Efectos naturales y socioeconómicos del Fenómeno
Linden, P.J., Day, X., Maskell, K. and Johnson, C.A. (eds.). Climatic
El Niño en Colombia. Bogotá, Colombia. Instituto de Hidrología,
Change 2001: The Scientifi c Basis. Contributions of Working Group
Meteorología y Estudios Ambientales de Colombia. Retrieved
I to the Third Assessment Report of the Intergovernmental Panel
May, 2004 from: http://www.ideam.gov.co/fenomenonino/
on Climate Change. Cambridge University Press, Cambridge, United
DOCUMENTOELNINO.pdf
Kingdom and New York. United States.
IGAC (1999). Zonifi cación Ecológica de la Región Pacífi co Colombiana.
ISAT 2001 Diagnóstico Situacional del Uso del DDT y el Control de la
Instituto Geográfi co Agustín Codazzi, Bogota, Colombia.
Malaria: Informe regional para Mexico y Centroamerica. Instituto de
IIAP (2001a). Agenda Pacífi co XXI, propuesta para la acción regional
Salud, Ambiente y Trabajo S.C./PAHO/GEF/UNEP/CEC/CCA/CCE.
del Pacífi co biodiverso en el presente milenio. Resumen ejecutivo.
Jouravlev, A. (2001). Administración del agua en América Latina
Instituto de Investigaciones Ambientales del Pacífi co, Ministerio del
y el Caribe en el umbral del siglo XXI. Recursos naturales e
Medio Ambiente, Departamento Nacional de Planeación, Programa
infraestructura No 27 (LC/L.1564-P). Comisión Económica de las
BID y Plan Pacífi co. Quibdo, Colombia.
Naciones Unidas para América Latina y el Caribe, Santiago, Chile.
IIAP (2001b). Perfi l Ambiental del Pacífi co Colombiano en Perfi l de los
Kiewcinsky, B. (1986). Contaminación Marina del Pacifi co de Panamá.
Recursos Naturales y del Medio Ambiente en Colombia. Sistema
Comisión Permanente del Pacífi co Sur. Serie Seminarios y Estudios
de Información Ambiental de Colombia. IDEAM/SINCHI/IAvH/IIAP/
(2):117-171.
INVEMAR, Colombia.
Leal, M.T., García, J.L. and Gelover, S. 2000. Calidad del Agua en la Bahía
INDERENA (1992). Leyva, P. (ed.). Colombia Pacífi
co, Proyecto
de Acapulco. Instituto Mexicano de Tecnología del Agua. Retrieved
BIOPACIFICO. Tomos I y II. INDERENA/DNP/GEF/PNUD/Fondo para
February, 2005 from: http://www.imta.mx/muestras/2000/ca_04_
la Protección del Medio Ambiente (COL/92/G31)/José Celestino
2000.pdf
Mutis/FEN. Retrieved April, 2004 from: http://www.banrep.gov.co
Levin, B. 2002. El Salvador va a una crisis de agua. Retrieved from: http:
INEGI (1998). Estadísticas del Medio Ambiente: México 1997. Instituto
//www.cesta-foe.org/articulos/02-10/crisis_de_agua.htm
Nacional de Estadística, Geografía e Informática, Aguascalientes,
Lezama-López, M. (2003). La experiencia del grupo de trabajo de
Mexico.
humedales. p 265-280 In: Nicaragua Aportes a un proceso de
INEGI (2000). Instituto Nacional de Estadistícas Geografi a e Informatica,
gestión de ecosistemas y el agua. Departamento de Ciencias
Mexico. Retrived April 2004 from: http://www.inegi.gob.mx/
Ambientales y Agraria Universidad Centroamericana, Managua
INPA (2000). Perfi l de la pesca y la acuicultura en Colombia. Informe
Nicaragua.
elaborado por Claudia Stella Beltrán Turriago y Abraham Alberto
Little, M. and Herrera, M. (1991). Checklist and catalogue of the fi sh
Villaneda Jiménez. Instituto Nacional de Pesca y Acuicultura,
recorded in the by-catch of the Ecuadorian shrimp fl eet. Agreement
Bogotá, Colombia.
Overseas Development Administration of the UK. Government/
INVEMAR (2003a). Programa holandés de asistencia para estudios de
Instituto Nacional de Pesca, Guayaquil, Ecuador.
cambio climático, Colombia: defi nición de la vulnerabilidad de los
Living Lakes (2005). Lake Chapala. Retrieved February, 2005 from: http:
sistemas biogeofísicos y socioeconómicos debido a un cambio en
//www.livinglakes.org/chapala/
el nivel del mar en la zona costera colombiana (Caribe continental,
Llort, M. and Montufar, J.C. (2002). El Plan Trifi nio y la cuenca compartida
Caribe insular y Pacífi co) y medidas para su adaptación. VII tomos.
del río Lempa de El Salvador, Guatemala y Honduras. Secretaria
Instituto de Investigaciones Marinas y Costeras, Programa de
Ejecutiva Trinacional, San Salvador, El Salvador. p 247-264 In:
investigación para la gestión marina y costera/GEZ. Santa Marta,
Memorias Día de las Américas /Tercer Foro Mundial sobre el Agua,
Colombia.
Miami, United States.
INVEMAR (2003b). Diagnostico de la calidad ambiental marina en el
López, O., De León, E. and Sánchez, S. (1996). Perfi l costero del Pacífi co de
caribe y Pacífi co colombiano. Red de vigilancia para la protección y
Panamá,.Ministerio de Planifi cación y Política Económica/Comisión
70
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Nacional del Medio Ambiente /Universidad de Panamá, Escuela
Ofi cina de Coordinación del Plan Puebla-Panamá (2001). Pan Puebla-
de Geógrafo Profesional. Informe a la Comisión Permanente del
Panamá-Diagnostico. Ofi
cina de Coordinación, Presidencia
Pacífi co Sur, Quito, Ecuador.
de la Republica, México. Retrieved May, 2004 from: http://
Loria, L.G., Jiménez, R. and Lizano, O.G. (2002). Radionucleídos naturales
ppp.sre.gob.mx/
y antropogénicos en el estuario del Golfo de Nicoya, Costa Rica. Top.
OPS/OMS (1999). El Huracán Mitch en Guatemala. Organización
Meteoro. Oceanog. 9(2):74-78.
Panamericana de la Salud Representación en Guatemala.
Lozano, J. and Pabón, J. (2005). Ascenso del nivel del mar. Presentation
OPS/OMS (2001a). Informe Regional sobre la evaluación 2000 en la
(ppt). Retrieved February, 2005 from: http://www.invemar.org.co/
región de las Américas: Agua potable y saneamiento básico-
redcostera1/invemar/docs/
Situación actual y perspectivas. Washington D.C., United States.
MARENA (2003). Estado del ambiente de Nicaragua, II Informe
OPS/OMS (2001b). Panama, Programa de Políticas Públicas y
GEO. Ministerio del Ambiente y los Recursos Naturales de
Salud, División de Salud y Desarrollo Humano y el Programa
Nicaragua,Managua, Nicaragua.
de Saneamiento Básico, División de Salud y Ambiente de la
Marín, R. (1992). Estadísticas sobre el recurso agua en Colombia.
Organización Panamericana de la Salud, Ofi cina Regional de
Segunda edición. Ministerio de Agricultura e Instituto de hidrología,
la Organización Mundial de la Salud. Informe Técnico No. 9.
meteorología y adecuación de tierras, ARFO Ltda., Santafé de
Washington D.C., United States.
Bogotá, Colombia.
OPS/OMS (2001c). El Salvador, Programa de Políticas Públicas y
MARN El Salvador (1997). Estrategia nacional, plan de acción y primer
Salud, División de Salud y Desarrollo Humano y el Programa
informe de país sobre diversidad biológica. Ministerio de Medio
de Saneamiento Básico, División de Salud y Ambiente de la
Ambiente y Recursos Naturales de El Salvador/GEF/PNUD, San
Organización Panamericana de la Salud, Ofi cina Regional de
Salvador, El Salvador.
la Organización Mundial de la Salud. Informe Técnico No. 6.
MARN El Salvador (2000). Majano, A.M., Aguilar, M. and López, E.
Washington, D.C., United States.
(eds.). Primera Comunicación Nacional sobre cambio climático.
OPS/OMS (2003). Jenkins, J. (ed.). Vulnerabilidad de los sistemas de
Ministerio de Medio Ambiente y Recursos Naturales de El Salvador,
abastecimiento de agua potable y saneamiento en áreas rurales
San Salvador, El Salvador.
de El Salvador. Washington D.C., United States.
MARN Guatemala. (2001). Guatemala: Primera Comunicación Nacional
OPS/OMS (2004). Numbers of reported cases of Dengue and Dengue
sobre Cambio Climático, Guatemala de la Asunción. Ministerio de
hemorrhagic fever (DHF), Region of the Americas (provisional
Ambiente y Recursos Naturales de Guatemala, Guatemala.
fi gures for reported and comfi rmed cases to week noted by each
MINAE (2000). Instituto Meteorológico Nacional (ed.). Primera
country). Retrieved June, 2004 from: www.paho.org
Comunicación Nacional ante la Convención Marco de las Naciones
Ostrom, E. (2000). El gobierno de los bienes comunes: la evolución de
Unidas de Cambio Climático. Ministerio del Ambiente y Energía de
las instituciones de acción colectiva. Universidad Autónoma de
Costa Rica, San José, Costa Rica.
México, Centro Regional de Investigaciones Multidisciplinarias.
MMA (2002a). Programa Nacional para la Conservación de las Tortugas
México.
Marinas y Continentales en Colombia. Ministerio del Medio
Páez, F. (1999). Contaminación por metales pesados en las costas de
Ambiente, Dirección General de Ecosistemas, Colombia.
México. Ciencia y Desarrollo 149:69-73.
MMA (2002b). Programa Nacional de Uso Sostenible, Manejo y
PAHO (2001). Regional Report on the Evaluation 2000 in the Region
Conservación de los Ecosistemas de Manglar. Ministerio del Medio
of the Americas: Water Supply and Sanitation, Current Status and
Ambiente, Dirección General de Ecosistemas, Colombia.
Prospects. Pan American Health Organization, Division of Health
MMA (2002c). Impacto de la tasa por utilización de agua en los diferentes
and Environment, Washington, D.C. United States.
sectores de la economía colombiana. Informe fi nal de consultoría.
Palacios, D. and Gerodette, T. (1996). Potential impact on artisanal gillnet
Ministerio del Medio Ambiente, Colombia.
fi sheries on small cetacean populations in the Eastern Tropical
MMA (2002d). Memorias del taller conjunto para la reglamentación de
Pacifi c. NOAA Administrative Report LJ-96-11.
las tasas por utilización de aguas. Ministerio del Medio Ambiente.,
Peña, J.J. (1995). Un modelo de caja aplicado al transporte de partículas
Bogotá, Colombia.
y tiempo de residencia del sector el Pindo, ensenada de Tumaco.
OECD (2003). Environmental Performance Reviews: Mexico. Organisation
Centro de Control de Contaminación del Pacífi co. Dirección General
for Economic Cooperation and Development, Paris, France.
Marítima. Boletín Científi co CCCP 5:05-35.
REFERENCES
71
Pérez, C.A., Poveda, G., Mesa, O., Carvajal, L.F. and Ochoa, A. (1995).
República de Colombia (2002). Arroyo-V. J.E., Maribell Gonzalez A.,
Evidencias de cambio climático en Colombia: tendencias y cambios
Abadía, A., Pardo L., and Ramírez-A, A. Diagnosis de la biodiversidad
de fase y amplitud de los ciclos anual y semianual. Retrieved
y ecosistemas en el Pacifi co Colombiano, Versión 02. Cali Valle Del
February, 2005 from: http://www.unesco.org.uy/phi/libros/enso/
Cauca, Ministerio Del Medio Ambiente, Instituto De Investigaciones
poveda.html
Ambientales Del Pacifi
co IIAP, Linea Base De Indicadores
Pineda-Polo, F. (1992). Biología y dinámica poblacional del camarón de
Ambientales, Colombia.
aguas someras Penaeus occidentales Streets, durante el año 1991, en
Restrepo, J.D. and Kjerve, B. (2000). Water discharge and sediment load
la costa Pacífi ca colombiana. Memorias VIII Seminario Nacional de
from the western slopes of Colombian Andes with focus on rio San
Ciencias y Tecnologías del Mar CCO 2:782-796.
Juan. The Journal of geology 108:17-33.
PNUD 2003. Informe sobre el desarrollo de los Recursos Hídricos en el
Reynolds, J. and Fraile, J. (2002). Presente y futuro de las aguas
mundo de las Naciones Unidas: Agua para todos, Agua para la Vida.
subterráneas en el valle central. In: Vargas, J. (ed.). Manejo integrado
Programa de las Naciones Unidas para el Desarrollo.
de aguas residuales, un reto para el futuro. UNED, San José, Costa
PNUD/EU (1998). Estado de la Region 1998, The State of the Region
Rica.
Report on the sustainable human development Central America.
Rivera-Arriaga, E. and Villalobos, G. (2001). The Coast of Mexico:
The Mandate of the State of the Region, San Jose Costa Rica.
approaches for its management. Ocean and Coastal Management
Programa de las Naciones Unidas para el Desarrollo/European
44:729-756.
Union. l
Rubio, E.R, Funes, C. and Gavidia, F.S. (2001). Evaluación de fuentes de
PNUMA (1999). Assessment of land-based sources and activities aff ecting
contaminación y actividades Humanas originadas en tierra que
the marine, coastal and associated freshwater environment in the
afectan ambientes marinos, costeros y dulceacuícolas asociados
South-East Pacifi c. UNEP Regional Seas Report and Studies No. 169.
en El Salvador. Informe al PAM/PNUMA, El Salvador.
UNEP/CPPS. The Hague, The Netherlands.
Rubio, R.E. (1994). Informe del estado del medio ambiente marino en el
PNUMA (2000). GEO América latina y el Caribe, perspectivas del Medio
area del Pacífi co de El Salvador. Informe a la Comision Permanente
Ambiente. Retrieved April, 2004 from: http://www.eco-index.org/
del Pacifi co Sur, Lima, Perú.
search/resultss.cfm?ProjectID=767
Rueda, M., Blanco, J, Narváez, J.C., Vitoria, E., Newmark, F. and Santos,
PNUMA (2001). Evaluación sobre las Fuentes terrestres y actividades que
M. (2003). Estado de los recursos sometidos a explotación en
afectan al medio marino, costero y de aguas dulces asociadas en la
Colombia. p 227-251 In: Informe del Estado de los Ambientes
Región el Pacífi co Nordeste. UNEP/ DEC/ NEP/EM.
Marinos y Costeros en Colombia: Año 2002. Serie de Publicaciones
PNUMA/IUCN (1988). Coral reefs of the world. Volume 1: Atlantic and
No. 8. INVEMAR, Colombia.
Eastern Pacifi c. UNEP Regional Seas Directories and Bibliographies.
Sainz, J. and Becerra, M. (2005). Los confl ictos por agua en México:
The World Conservation Union/United Nations Environmental
Avances de investigación. Instituto Nacional de Ecología, Coyoacán,
Programme, Gland, Switzerland and Nairobi, Kenya.
México.
Poveda, G and Rojas W. (1997). Evidencias de la asociación entre brotes
Sánchez, M.J. (2001). Evaluación nacional fuentes de contaminación y
epidémicos de malaria en Colombia y el fenómeno del Niño-
actividades humanas originadas en tierra que afectan los ambientes
Oscilación Sur. Revista de la Academia de Ciencias exactas, Físicas
marinos, costeros y dulceacuícolas asociados al litoral Pacífi co y
y Naturales Vol. VXXI (81).
Golfo de Fonseca de Nicaragua. Programa de Acción Mundial para
Prahl., H., Cantera J. and Contreras R. (1990). Manglares y hombres
la Protección del Medio Marino frente a las Actividades Realizadas
del Pacífi co Colombiano. Fondo FEN/CONCIENCIAS. Bogotá,
en Tierra, Managua, Nicaragua.
Colombia.
Santodomingo, N. and Rueda, M. (2003). Diversidad de especies marinas
Pratt. L. and Girot, A.P. (1999). Perfi l ejecutivo para el dialogo regional
en Colombia. p 208-228. In: Informe del Estado de los Ambientes
sobre medio ambiente: Subregion Mesoamerica. CLACOS/INCAE
Marinos y Costeros en Colombia: Año 2002. Serie de Publicaciones
Banco Interamericano de Desarrollo BI. Retrieved June, 2004 from:
No. 8. INVEMAR. Colombia.
http//www.idb.org
Schoijet, M. (2002). La evolución de los recursos pesqueros a escala
Ramírez, O. and Espejel, I. (2001). Las aguas residuales municipales como
mundial. Problemas del Desarrollo. Revista Latinoamericana de
fuentes terrestres de contaminación del medio marino costero de la
Economía 33(129):103-125.
Region de America Latina y el Caribe. GPA/PNUMA, México.
Sea Around Us Project (2002). A global database on marine
fi sheries and ecosystems. Fisheries Centre, University of British
72
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Columbia, Vancouver, Canada. Retrieved April, 2004 from: http:
los Ambientes Marinos y Costeros en Colombia: Año 2002. Serie de
//seaaroundus.org/lme/SummaryInfo.aspx?LME=11
Publicaciones No. 8. INVEMAR. Colombia.
SEMAR (2004). Atlas de la Contaminación Marina en el Mar Territorial
Vörösmarty, C.J., Mrouthier, A., Wright, T., Baker, C. Fernández-Jauregui,
y Zonas Costeras de la República Mexicana. Secretaría de Marina
A. and Donoso, M.C. (1998). A regional hydrometerorological data
Armada de México, México.
network for South America, Central America and the Caribbean.
SEMARNAT (2002). Segundo informe de labores. Secretaría de medio
Retrieved April, 2004 from: http://www.r-hydronet.sr.unh.edu
ambiente y recursos naturales, México.
WCMC (1996). Southeast Pacifi c. In: Groombridge, B. and Jenkins ,M.D.
SEMARNAT (2004). Problemática del lago de Chapala. Retrieved
(eds). The Diversity of the Seas- A regional approach. WCMC
February, 2005 from: http://www.semarnat.gob.mx/regiones/
Biodiversity Series No. 4. World Conservation Monitoring Centre,
chapala/problematica.shtml
Cambridge, United Kingdom.
SNET 2002. Condiciones hidrológicas en Diciembre 2002. Servicio
WFP/FAO (2002). Standardised food and livelihood assessment in
Hidrológico Nacional de El Salvador. Boletín de Condiciones
support of the Central American PRRO. World Food Programme/
hidrológicas No 08, 2002.
Food and Agriculture Organization, Rome, Italy.
Steer, R., Arias-Isaza, F., Ramos, A., Sierra-Correa, P.C. and Alonso, D.
Windevoxhel, N., Rodríguez, J.J., and Lahmann, E. (2000). Situation of
(1997). Documento base para la elaboración de la política nacional
integrated coastal zone manamagement in Central American:
de ordenamiento ambiental y desarrollo sostenible de las zonas
Experiences of the IUCN Wetlands and Coastal Zone Conservation
costeras colombianas. Consultoría para el ministerio del medio
Program, Moravia, San Jose Costa Rica. IUCN/ORMA.
Ambiente, Colombia.
Wo-Ching, S.E. and Cordero, C. (2001). Evaluación nacional sobre fuentes
Tierramerica (2004). Agua: No hay escasez, sino desperdicio e
de contaminación y actividades humanas originadas en tierra que
inefi ciencia. Retrieved March, 2004 from: http://tierramerica.net/
afectan ambientes marinos, costeros y dulce acuícola asociados
2004/0320/noticias3.shtml
en Costa Rica. Informe Centro de Derecho Ambiental y Recursos
Tribunal Centroamericano del Agua (2004). Enfermedades hídricas.
Naturales CEDARENA/GPA, San José, Colombia and The Hague,
Retrieved June, 2004 from http://www.tragua.com/
The Netherlands.
UNEP (2000). Recommendations for decision-making on municipal
WRI (2004). Earth trends: Environmental information. Retrieved June,
wastewater. United Nations Environmental Programme/ Global
2004 from: www.earthtrends.wri.org
Programme of Action for the Protection of the Marine Environment
Yepes, F. (ed.) (1990). La salud en Colombia. Estudio Sectorial de Salud,
from Land-based Activities, Nairobi, Kenya and The Hague, the
Ministerio de Salud, Departamento Nacional de Planeación Bogotá,
Netherlands.
Colombia.
UNEP-GPA (2001). Latín American Workshop on Municipal Wastewater:
Zambrano, C. and Rubiano, D. (1996). Mapas del bosque de manglar
Final Report México City, 10th-12th September, 2001, UNEP/LAC-GPA
de la costa Pacífi ca colombiana, años 1969, 1996 y multitemporal.
1/7-, Mexico.
Informe Técnico 7, Bogotá, OIMT/MMA, Colombia.
Ustate, Z. (2002). Diagnóstico de la cadena productiva pesquera en
Colombia Estudio de prospectiva para la cadena productiva de la
Personal communication
industria pesquera en la región de la costa el Pacífi co en América
Leal Ascencio, T. (Instituto Mexicano de Tecnología del Agua, Mexico)
del Sur. Project N° US/RLA/02/149, United Nations Industrial
Muñoz-Pineda, C (Secretaría de medio ambiente y recursos naturales,
Development Organization, Vienna, Austria.
SEMARNAT, Mexico)
Vargas, C. (1998). Gestión integrada de los recursos hídricos en la
Zilberman, D. (University of California at Berkeley, United States)
cuenca del canal de Panamá. p 82-98 In: Gestión integrada de los
recursos hídricos en Mesoamérica. Organization of American States,
Washington D.C., United Status.
Veenstra, S., G.J. Alaerts, and M. Bijlsma. 1997. Technology Selection. p
46-72 In: Helmer, R. and Hespanol, I. (eds.). Water Pollution Control.
E & FN Spon, London, United Kingdom.
Vélez, A.M., Marín, G.B.J. and Ramírez, G. (2003). La calidad ambiental
marina y costera en Colombia. p 48-78 In: Informe del Estado de
REFERENCES
73
Annexes
Annex I
List of contributing authors and organisations
Name
Country
Institution
Field
Ulises Munaylla
Peru
CPPS
Regional Coordinator. GIWA methodology.
Fernando Félix
Ecuador
CPPS
Coordination, assistant, edition
Marcia Marques
Brazil
GIWA
Regional Coordinator for Latin America and the Caribbean
Juan Carlos Belausteguigoitia
Mexico
GIWA
Coordinator for the Southern Hemisphere
Fisheries assessment and management, coastal zone management,
Antonio Díaz de León Corral¹
Mexico
National Institute of Fisheries/ The Mexican School (LEAD Program)
oceans environment and development
Corina Warfield¹
Mexico
Goldman School of Public Policy. University of California, Berkeley
Management environmental policies
Juanito Rus¹
Mexico
Goldman School of Public Policy. University of California, Berkeley
Management environmental policies
Ian Hart¹
Mexico
Goldman School of Public Policy. University of California, Berkeley
Management environmental policies
Josh Bode¹
Mexico
Goldman School of Public Policy. University of California, Berkeley
Management environmental policies
Iván Flores Morales
Panama
Maritime Authority of Panama AMP
Oceanography
Rocío Ramírez
Panama
Maritime Authority of Panama AMP
Coastal Zones Management.
Rodolfo Tejada
Guatemala
Consultant
Management
Mario Coto H
Costa Rica
Ministry of the Environment and Energy MINAE
Administration of protected areas
Paula Cristina Sierra
Colombia
Institute of Marine research INVEMAR
Marine biology - Coastal Zones Management.
Maria Cristina Bernal²
Colombia
Institute of Marine research INVEMAR
Biology- Legislation and Maritime policy
Walberto Troncoso²
Colombia
Institute of Marine research INVEMAR. Program CAM
Marine biology
Vanesa Torres²
Colombia
Colombian Commission of Oceanography
Biology-
Camilo Botero
Colombia
Colombian Commission of Oceanography
Management environmental policies
Luz M. Vis Londoño
Colombia
Institute of Marine research INVEMAR
Economic valuation of resources
Francisco Arias²
Colombia
Institute of Marine research INVEMAR
Marine Biology. Coastal Zones Management.
Milton Hermen Ruiz
Colombia
Professional Environmental Advise Consultancy
Environmental management
Maria E. Posada
Colombia
Ministry of Foreign Affairs
Environmental
Juan Acuna
Colombia
Ministry of Foreign Affairs
Socio-economic, environment
Patricia Flores
Ecuador
CPPS
Coordination, assistant
Mario Hurtado³
Ecuador
Consultant
Marine biology - conservation
J.Jairo Escobar R
Colombia
Consultant
Marine biology - pollution
¹ Task team Southwest Mexico Subsystem
² Task team Colombian Pacific Subsystem
³ Consultant, first draft SR65.
Consultant, draft of the Subsystem Central American Pacific.
74
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Annex II
Detailed scoring tables
I: Freshwater shortage
II: Pollution
Weight
Weight
Environmental
Environmental
Environmental issues
Score
Weight
averaged
Environmental issues
Score
Weight
averaged
concern
concern
score
score
1. Modification of stream flow
2
20
Freshwater shortage
2
4. Microbiological
2
35
Pollution
1.85
2. Pollution of existing supplies
2
50
5. Eutrophication
1
10
3. Changes in the water table
2
30
6. Chemical
2
25
7. Suspended solids
1
5
Criteria for Economics impacts
Raw score
Score Weight %
8. Solid wastes
2
15
Very small
Very large
Size of economic or public sectors affected
2
35
0 1 2 3
9. Thermal
0
0
Minimum
Severe
Degree of impact (cost, output changes etc.)
3
55
10. Radionuclides
0
0
0 1 2 3
Occasion/Short
Continuous
Frequency/Duration
2
10
11. Spills
2
10
0 1 2 3
Weight average score for Economic impacts
2.55
Criteria for Economics impacts
Raw score
Score Weight %
Criteria for Health impacts
Raw score
Score Weight %
Very small
Very large
Very small
Very large
Size of economic or public sectors affected
2
30
Number of people affected
2
50
0 1 2 3
0 1 2 3
Minimum
Severe
Minimum
Severe
Degree of impact (cost, output changes etc.)
2
50
Degree of severity
2
40
0 1 2 3
0 1 2 3
Occasion/Short
Continuous
Occasion/Short
Continuous
Frequency/Duration
2
20
Frequency/Duration
2
10
0 1 2 3
0 1 2 3
Weight average score for Economic impacts
2.0
Weight average score for Health impacts
2.0
Criteria for Health impacts
Raw score
Score Weight %
Criteria for Other social and
Raw score
Score Weight %
community impacts
Very small
Very large
Number of people affected
2
50
Very small
Very large
0 1 2 3
Number and/or size of community affected
2
30
0 1 2 3
Minimum
Severe
Degree of severity
2
40
Minimum
Severe
0 1 2 3
Degree of severity
2
50
0 1 2 3
Occasion/Short
Continuous
Frequency/Duration
2
10
Occasion/Short
Continuous
0 1 2 3
Frequency/Duration
2
20
0 1 2 3
Weight average score for Health impacts
2.0
Weight average score for Other social and community impacts
2.0
Criteria for Other social and
Raw score
Score Weight %
community impacts
Very small
Very large
Number and/or size of community affected
2
45
0 1 2 3
Minimum
Severe
Degree of severity
2
35
0 1 2 3
Occasion/Short
Continuous
Frequency/Duration
2
20
0 1 2 3
Weight average score for Other social and community impacts
2.0
ANNEXES
75
III: Habitat and community modification
IV: Unsustainable exploitation of fish
Weight
and other living resources
Environmental
Environmental issues
Score
Weight
averaged
concern
score
Weight
Environmental
Environmental issues
Score
Weight %
averaged
Habitat and community
concern
12. Loss of ecosystems
2
40
2
score
modification
13. Modification of ecosystems or
Unsustainable
14. Overexploitation
3
40
2.25
ecotones, including community
2
60
exploitation of fish
structure and/or species composition
15. Excessive by-catch and
2
30
discards
16. Destructive fishing practices
2
20
Criteria for Economics impacts
Raw score
Score Weight %
Very small
Very large
17. Decreased viability of stock
Size of economic or public sectors affected
2
30
0
5
0 1 2 3
through pollution and disease
Minimum
Severe
18. Impact on biological and
Degree of impact (cost, output changes etc.)
2
40
1
5
0 1 2 3
genetic diversity
Occasion/Short
Continuous
Frequency/Duration
2
30
0 1 2 3
Criteria for Economics impacts
Raw score
Score Weight %
Weight average score for Economic impacts
2.0
Very small
Very large
Size of economic or public sectors affected
2
25
Criteria for Health impacts
Raw score
Score Weight %
0 1 2 3
Minimum
Severe
Very small
Very large
Degree of impact (cost, output changes etc.)
2
50
Number of people affected
0
0 1 2 3
0 1 2 3
Occasion/Short
Continuous
Minimum
Severe
Frequency/Duration
2
25
Degree of severity
0
0 1 2 3
0 1 2 3
Occasion/Short
Continuous
Weight average score for Economic impacts
2.0
Frequency/Duration
0
0 1 2 3
Criteria for Health impacts
Raw score
Score Weight %
Weight average score for Health impacts
0
Very small
Very large
Criteria for Other social and
Number of people affected
0
Raw score
Score Weight %
0 1 2 3
community impacts
Minimum
Severe
Very small
Very large
Degree of severity
0
Number and/or size of community affected
2
40
0 1 2 3
0 1 2 3
Occasion/Short
Continuous
Minimum
Severe
Frequency/Duration
0
Degree of severity
2
40
0 1 2 3
0 1 2 3
Occasion/Short
Continuous
Weight average score for Health impacts
0
Frequency/Duration
2
20
0 1 2 3
Criteria for Other social and
Raw score
Score Weight %
Weight average score for Other social and community impacts
2.0
community impacts
Very small
Very large
Number and/or size of community affected
2
35
0 1 2 3
Minimum
Severe
Degree of severity
2
40
0 1 2 3
Occasion/Short
Continuous
Frequency/Duration
2
25
0 1 2 3
Weight average score for Other social and community impacts
2.0
76
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
V: Global change
Weight
Environmental
Environmental issues
Score
Weight
averaged
concern
score
19. Changes in the hydrological cycle
2
57
Global change
1.57
20. Sea level change
1
43
21. Increased UV-B radiation as a
0
0
result of ozone depletion
22. Changes in ocean CO2
0
0
source/sink function
Criteria for Economics impacts
Raw score
Score Weight %
Very small
Very large
Size of economic or public sectors affected
3
40
0 1 2 3
Minimum
Severe
Degree of impact (cost, output changes etc.)
2
40
0 1 2 3
Occasion/Short
Continuous
Frequency/Duration
2
20
0 1 2 3
Weight average score for Economic impacts
2.4
Criteria for Health impacts
Raw score
Score Weight %
Very small
Very large
Number of people affected
2
40
0 1 2 3
Minimum
Severe
Degree of severity
2
40
0 1 2 3
Occasion/Short
Continuous
Frequency/Duration
1
20
0 1 2 3
Weight average score for Health impacts
1.8
Criteria for Other social and
Raw score
Score Weight %
community impacts
Very small
Very large
Number and/or size of community affected
0
40
0 1 2 3
Minimum
Severe
Degree of severity
0
40
0 1 2 3
Occasion/Short
Continuous
Frequency/Duration
0
20
0 1 2 3
Weight average score for Other social and community impacts
0
ANNEXES
77
Annex III
Regional agreements, conventions and projects
Central American Ecological Summit on Sustainable Development
use and management of water resources.
(Cumbre Ecológica Centroamericana para el Desarrollo 5. Develop case studies for implementing the Local Dialogues and
Sostenible), Managua, Nicaragua, 13th October, 1994.
activities that involve the sustainable use of water.
6. Develop methodologies to assess the economic value of water
The Presidents of the Republics of Costa Rica, El Salvador, Guatemala,
resources.
Honduras, Nicaragua, and Panama, and the Representative of the First
7. Produce a Historical Record of the Meeting and distribute internally
Ministry of Belize, met at the Central American Ecological Summit on
within each country.
Sustainable Development. They made the following commitments,
8. Based on the criteria for determining the locations, each country
among others:
should provide technical support for the proposed locations.
9. Interact as a Virtual Network by means of an electronic forum for
Water
discussion.
To prioritise policies and legislation regarding the management and
10. Compile experiences and good practices in the region in order to
conservation of hydrological resources, including, among others,
exchange information.
the strengthening of the legal and institutional framework, and
11. Design a proposal to be presented in Bonn, which should be
coordination mechanisms between the authorities in charge of the
regional in nature in order to create a larger impact, although this
management and administration of water resources either for human
does not eliminate the possibility of generating pilot projects at the
consumption, irrigation or electricity generation. Commitments
micro-basin level.
were made for respective authorities to update studies about
12. A regional commission was formed to follow up the commitments of
Central American basins in order to prepare specifi c projects for their
"A Dialogue about Water, Food and Environmental Sustainability."
sustainable use and management.
Convention for Cooperation in the Protection and Sustainable
Pollution control
Development of the Marine and Coastal Environment of the
A two year period was allowed for the countries of the region to
North-East Pacifi c (Antigua Convention), Antigua, Guatemala,
implement mechanisms for the monitoring and control of pollution.
18th February 2002.
The Central American Commission of Environment and Development
The aim of this Convention is to establish a regional co-operation
is responsible for the gradual implementation of the commitments,
framework to encourage and facilitate the sustainable development
the establishment of decentralisation mechanisms for surveillance and
of marine and coastal resources of the countries of the North-
control, and the promotion of public participation in these processes.
East Pacifi c for the benefi t of present and future generations. The
contracting parties recognised the need to protect and preserve the
A Dialogue about Water, Food and Environmental
marine and coastal environment of the North East Pacifi c against all
Sustainability, San Jose, Costa Rica, 1st November, 2001.
kinds of environmental pollution and degradation. The ecological,
Conclusions and commitments:
economic, social and cultural value of the area was seen as a means
1. Foment integrated water resources management and take into
of bonding the countries of the region. The scope of application of
consideration the social, economic and environmental values in
the Convention comprises the maritime areas of the North East Pacifi c,
order to improve the quality of life.
defi ned in conformity with the United Nations Convention on the Law
2. Adopt integrated water resources management, with the river
of the Sea. The Secretariat of the Convention is the Central American
basins being the planning unit.
Commission for Maritime Transportation (COCATRAM) located in
3. Promote opportunities for dialogue and participation of
Managua, Nicaragua.
communities and private, governmental, agricultural and
environmental sectors.
Marine Corridor for the Conservation and Sustainable Development of
4. Formulate guidelines and policies that will assist in the sustainable
the South East Tropical Pacifi c
78
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
This corridor was established on 2nd April 2004 and embraces the islands
in order to eliminate the causes of marine environmental degradation,
Galapagos (Ecuador), Gorgona and Malpelo (Colombia), Coiba (Panama)
as well as the loss of biodiversity and food security due to over-
and Cocos (Costa Rica). The initiative reinforces cooperation between
exploitation. For the Central American Pacifi c coast, the LME stretches
these countries in order to protect biological diversity.
from Cape Corrientes in Mexico in the north to Ecuador in the south,
including the basins of Guatemala and Panama and the Peru-Chile
Large Marine Ecosystems (LMEs) of the world
trench. The system is located between the California and Humboldt
Several institutions are providing and fostering scientifi c and technical
currents.
support for developing countries to establish new policies and actions
Conventions, protocols and projects relevant to the colombian
pacific sub-system
Convention for the Protection of the Marine Environment and
the General Authority of the Plan of Action remains with the regular
Coastal Areas in the South East Pacifi c (1981)
meeting of Government representatives (Intergovernmental
This Convention, also known as the Lima Convention, was signed on 12th
Meetings). They are mandated to assess the implementation progress
November, 1981 by Chile, Colombia, Ecuador, Peru and Panama. It was
of the Plan of Action and approve the projects and activities.
initiated by the United Nations Environment Programme (UNEP). The
main objective of the Convention is to promote regional cooperation
Protocol for the Conservation and Management of Protected
in the protection of the marine environment and coastal zones of the
Marine and Coastal Areas of the South East Pacifi c (1989)
South East Pacifi c, emphasizing the economic, social and cultural
This Protocol contains regulations regarding protected areas such
signifi cance of the South Pacifi c.
as common criteria to establish protected areas and the regulation
of activities through an integrated environmental management
Plan of Action for the Protection of the Marine Environment and
mechanism. Guidelines include, among others, buff er areas; measures to
Coastal Areas of the South Pacifi c (1981)
prevent, reduce and control pollution in protected areas; environmental
This Plan has the same characteristics as other UNEP Regional Seas
impact assessments; establishing an integrated analysis procedure;
Programmes. The main objective of this regional cooperation
scientifi c and technical cooperation; and promotion of stakeholder
mechanism is to protect the marine environment and coastal areas
participation and environmental education. This protocol was approved
in order to safeguard the heath and well being of current and future
by Colombia through Law 12 (1992).
generations. The general legal framework of the Plan of Action of the
South East Pacifi c is the Convention for the Protection of the Marine
Protocol on the Program for the Regional Study of the "El Niño"
Environment and Coastal Areas of the South East Pacifi c. The Plan of
Phenomenon in the South East Pacifi c (ERFEN) (1992)
Action for the South East Pacifi c has the following components:
The member States of the Permanent Commission for the South Pacifi c
Environmental assessment: This provides the scientifi c basis to
(CPPS; Chile, Colombia, Ecuador and Peru) signed this protocol on 6th
implement the other components of the Plan. It comprises an
November 1992 in Callao, Peru. The aim of ERFEN is to forecast ocean-
assessment of the pollution caused by oil spills; the degree of
atmospheric changes with suffi
cient warning time to allow the issue of
pollution caused by industrial, mining and agricultural wastes and
policies and emergency measures to limit the impact on productive
their eff ects; and pollution caused by domestic wastes, radioactive
activities such as fi shing, agriculture and industry, among others.
pollution, and from the atmosphere, among others.
Environmental management: Formulation and application of
Framework Agreement for the Conservation of Living
programmes to prevent, monitor, reduce and eliminate pollution.
Resources on the High Seas of the Southeast Pacifi c (Galapagos
Legal component: The development of regional instruments
Agreement 2000)
constitutes a major achievement of the Plan of Action.
The member States of CPPS signed this agreement in 2000. The main
Institutional
and
fi nancial mechanisms: According to this component,
objective of this Agreement is to defi ne the legal framework for the
ANNEXES
79
conservation and management of living marine resources in the high
objective of the project is to contribute towards the consolidation
seas of the South East Pacifi c, with special reference to straddling and
of a new development strategy, based on scientifi c knowledge, and
highly migratory fi sh populations. The Agreement is applicable to the
to identify options for the management of biodiversity in order to
high seas beyond the external limits of the EEZ of the countries located
guarantee its protection and sustainable use by local communities. The
on the 120° W meridian between 5° N and 60° S.
goals of the project include, among others: i) assessment of the state
of the region's biodiversity and the current practices aff ecting its use
Pacifi c Agenda 21
and conservation; ii) assessment of the dynamics and eff ects of agro-
Pacifi c Agenda 21 has adopted a cultural approach to changing the
ecological systems; iii) development of conceptual and methodological
traditional model of communication between governments and
approaches for the valuation of biodiversity and environmental services;
Pacifi c communities. It attempts to deal with social problems involving
iv) strengthening of communication, education and social organisation
various stakeholders and to fi nd solutions to problems that threaten the
processes related to the conservation and exploitation of biodiversity;
environmental and cultural diversity of the Colombian Pacifi c region.
v) training of authorities about policies, planning and decentralized
The objective of Pacifi c Agenda 21 is to provide a local perspective,
management of biodiversity; vi) training of local people who are
through the participation of stakeholders, to long-term policies, plans
involved in conservation and the sustainable use of biodiversity; and
and programmes for the development of this area, taking into account
vii) institutional coordination with other regional and national plans,
the ethnic, cultural, social and economic realities of the Colombian
programmes and projects (INDERENA 1992).
Pacifi c (IIAP 2001a).
Project Biopacifi co
This project, implemented by INDERENA and the National Department
of Planning, focuses on the Choco biogeographic region. The general
80
GIWA REGIONAL ASSESSMENT 65 EASTERN EQUATORIAL PACIFIC
Annex IV
Fee-and-rebate system (Southwest Mexico sub-system)
Adjustable implementation features of fees and rebates
Basing threshold levels on environmental health standards places the
A fee-and-rebate system for municipal waste can be adapted for
main focus on safeguarding the local environment (as opposed to
specifi c requirements. There are opportunities to decide on the number
aggregate watershed pollution). Standards have frequently been set in
and features of municipalities in the programme, the threshold or target
the form of Total Maximum Daily Loads maximum pollution levels on
level of pollution, and the size of the rebates and fees. In addition,
waterways where the wastewater is discharged. This method places a
innovative programmes have started to integrate fee and rebate
heavier burden on large cities and does little to reduce the pollution per
systems with tradable pollution permits.
capita in smaller cities and cities that discharge wastewater into larger
waterways. The population of the city and the size of the receiving
Which cities to include
water body aff ect the overall pollution levels in waterways. Large cities
A fee-and-rebate system does not have to include every municipality.
can reduce wastewater pollution per capita, but have few options to
Given that most municipal waste stems from urban areas and that wide
reduce the overall city population.
gaps in fi nancial resources exist between urban and rural zones, it is
more practical to focus a fee-and-rebate system on larger cities. The
Setting fees and rebates
population threshold can be set by SEMARNAT. Mexico already has
When it comes to municipal water pollution, the commitment to
diff erent water infrastructure policies for rural and urban areas. The
a fee-and-rebate system has to be credible and long-term. Cities
same distinctions can be retained in the implementation of a fee-and-
will make decisions about whether or not to invest in wastewater
rebate system.
treatment infrastructure based on expected future returns. Year-to-
year uncertainty about the size of the rebates and fees complicates
Setting pollution thresholds
local decisions about investment in water pollution infrastructure,
Threshold limits for pollution where rebates switch to fees have to
and may deter investment. Nonetheless, this does not mean fees and
be set. The thresholds can be based on the prior history of pollution; the
rebates must remain fi xed. It does, however, require advanced warning
population of the city; or environmental health indicators.
regarding upcoming changes to the structure of the fee and rebate
system.
Basing threshold levels on prior history requires every city, regardless
of their past history of pollution, to make additional eff ort to meet the
A fi ve year timetable of fee-and-rebate changes is recommended
threshold. This method favours cities which have not introduced any
so that municipalities can calculate the costs and benefi ts of their
pollution abatement methods. These municipalities will usually be
investments in wastewater infrastructure. Although the fee changes
able to take advantage of more lower-cost technologies than cities
require some advance notice, the penalties and rebates themselves do
that were reducing water pollution before the implementation of fees
not have to be fi xed in a given year. Penalties and rebates can be graded.
and rebates.
SEMARNAT can charge smaller fees per-pollution-unit to municipalities
that exceed the threshold by only a little and larger fees per-pollution-
Basing allowable pollution levels on a municipality's population
unit for those that signifi cantly exceed threshold levels.
provides room for adjustment, and rewards cities who have already
made an eff ort to reduce and/or treat water pollution. Allowing time
for municipalities to update their wastewater infrastructure capacity
prior to implementation increases the political viability of the fee and
rebate structure.
ANNEXES
81
The Global International
Waters Assessment
This report presents the results of the Global International Waters
Adequately managing the world's aquatic resources for the benefi t of
Assessment (GIWA) of the transboundary waters of the Eastern
all is, for a variety of reasons, a very complex task. The liquid state of
Equatorial Pacifi c region. This and the subsequent chapter off er a
the most of the world's water means that, without the construction
background that describes the impetus behind the establishment of
of reservoirs, dams and canals it is free to fl ow wherever the laws of
GIWA, its objectives and how the GIWA was implemented.
nature dictate. Water is, therefore, a vector transporting not only a
wide variety of valuable resources but also problems from one area
to another. The effl
uents emanating from environmentally destructive
activities in upstream drainage areas are propagated downstream
The need for a global
and can aff ect other areas considerable distances away. In the case of
international waters
transboundary river basins, such as the Nile, Amazon and Niger, the
assessment
impacts are transported across national borders and can be observed
in the numerous countries situated within their catchments. In the case
of large oceanic currents, the impacts can even be propagated between
Globally, people are becoming increasingly aware of the degradation of
continents (AMAP 1998). Therefore, the inextricable linkages within
the world's water bodies. Disasters from fl oods and droughts, frequently
and between both freshwater and marine environments dictates that
reported in the media, are considered to be linked with ongoing global
management of aquatic resources ought to be implemented through
climate change (IPCC 2001), accidents involving large ships pollute public
a drainage basin approach.
beaches and threaten marine life and almost every commercial fi sh stock
is exploited beyond sustainable limits - it is estimated that the global
In addition, there is growing appreciation of the incongruence
stocks of large predatory fi sh have declined to less that 10% of pre-
between the transboundary nature of many aquatic resources and the
industrial fi shing levels (Myers & Worm 2003). Further, more than 1 billion
traditional introspective nationally focused approaches to managing
people worldwide lack access to safe drinking water and 2 billion people
those resources. Water, unlike laws and management plans, does not
lack proper sanitation which causes approximately 4 billion cases of
respect national borders and, as a consequence, if future management
diarrhoea each year and results in the death of 2.2 million people, mostly
of water and aquatic resources is to be successful, then a shift in focus
children younger than fi ve (WHO-UNICEF 2002). Moreover, freshwater
towards international cooperation and intergovernmental agreements
and marine habitats are destroyed by infrastructure developments,
is required (UN 1972). Furthermore, the complexity of managing the
dams, roads, ports and human settlements (Brinson & Malvárez 2002,
world's water resources is exacerbated by the dependence of a great
Kennish 2002). As a consequence, there is growing public concern
variety of domestic and industrial activities on those resources. As a
regarding the declining quality and quantity of the world's aquatic
consequence, cross-sectoral multidisciplinary approaches that integrate
resources because of human activities, which has resulted in mounting
environmental, socio-economic and development aspects into
pressure on governments and decision makers to institute new and
management must be adopted. Unfortunately however, the scientifi c
innovative policies to manage those resources in a sustainable way
information or capacity within each discipline is often not available or
ensuring their availability for future generations.
is inadequately translated for use by managers, decision makers and
GLOBAL INTERNATIONAL WATERS ASSESSMENT
i
policy developers. These inadequacies constitute a serious impediment
The Global Environment Facility (GEF)
to the implementation of urgently needed innovative policies.
The Global Environment Facility forges international co-operation and fi nances actions to address
six critical threats to the global environment: biodiversity loss, climate change, degradation of
international waters, ozone depletion, land degradation, and persistent organic pollutants (POPs).
Continual assessment of the prevailing and future threats to aquatic
The overall strategic thrust of GEF-funded international waters activities is to meet the incremental
ecosystems and their implications for human populations is essential if
costs of: (a) assisting groups of countries to better understand the environmental concerns of
their international waters and work collaboratively to address them; (b) building the capacity
governments and decision makers are going to be able to make strategic
of existing institutions to utilise a more comprehensive approach for addressing transboundary
policy and management decisions that promote the sustainable use of
water-related environmental concerns; and (c) implementing measures that address the priority
transboundary environmental concerns. The goal is to assist countries to utilise the full range of
those resources and respond to the growing concerns of the general
technical, economic, fi nancial, regulatory, and institutional measures needed to operationalise
public. Although many assessments of aquatic resources are being
sustainable development strategies for international waters.
conducted by local, national, regional and international bodies, past
United Nations Environment Programme (UNEP)
assessments have often concentrated on specifi c themes, such as
United Nations Environment Programme, established in 1972, is the voice for the environment
biodiversity or persistent toxic substances, or have focused only on
within the United Nations system. The mission of UNEP is to provide leadership and encourage
partnership in caring for the environment by inspiring, informing, and enabling nations and
marine or freshwaters. A globally coherent, drainage basin based
peoples to improve their quality of life without compromising that of future generations.
assessment that embraces the inextricable links between transboundary
UNEP work encompasses:
freshwater and marine systems, and between environmental and
Assessing global, regional and national environmental conditions and trends;
Developing international and national environmental instruments;
societal issues, has never been conducted previously.
Strengthening institutions for the wise management of the environment;
Facilitating the transfer of knowledge and technology for sustainable development;
Encouraging new partnerships and mind-sets within civil society and the private sector.
International call for action
University of Kalmar
University of Kalmar hosts the GIWA Co-ordination Offi ce and provides scientifi c advice and
administrative and technical assistance to GIWA. University of Kalmar is situated on the coast of
The need for a holistic assessment of transboundary waters in order to
the Baltic Sea. The city has a long tradition of higher education; teachers and marine offi cers have
been educated in Kalmar since the middle of the 19th century. Today, natural science is a priority
respond to growing public concerns and provide advice to governments
area which gives Kalmar a unique educational and research profi le compared with other smaller
universities in Sweden. Of particular relevance for GIWA is the established research in aquatic and
and decision makers regarding the management of aquatic resources
environmental science. Issues linked to the concept of sustainable development are implemented
was recognised by several international bodies focusing on the global
by the research programme Natural Resources Management and Agenda 21 Research School.
environment. In particular, the Global Environment Facility (GEF)
Since its establishment GIWA has grown to become an integral part of University activities.
The GIWA Co-ordination offi ce and GIWA Core team are located at the Kalmarsund Laboratory, the
observed that the International Waters (IW) component of the GEF
university centre for water-related research. Senior scientists appointed by the University are actively
suff ered from the lack of a global assessment which made it diffi
cult
involved in the GIWA peer-review and steering groups. As a result of the cooperation the University
can offer courses and seminars related to GIWA objectives and international water issues.
to prioritise international water projects, particularly considering
the inadequate understanding of the nature and root causes of
environmental problems. In 1996, at its fourth meeting in Nairobi, the
causes of degradation of the transboundary aquatic environment and
GEF Scientifi c and Technical Advisory Panel (STAP), noted that: "Lack of
options for addressing them. These pro cesses led to the development
an International Waters Assessment comparable with that of the IPCC, the
of the Global International Waters Assessment (GIWA) that would be
Global Biodiversity Assessment, and the Stratospheric Ozone Assessment,
implemented by the United Nations Environment Programme (UNEP) in
was a unique and serious impediment to the implementation of the
conjunction with the University of Kalmar, Sweden, on behalf of the GEF.
International Waters Component of the GEF".
The GIWA was inaugurated in Kalmar in October 1999 by the Executive
Director of UNEP, Dr. Klaus Töpfer, and the late Swedish Minister of the
The urgent need for an assessment of the causes of environmental
Environment, Kjell Larsson. On this occasion Dr. Töpfer stated: "GIWA
degradation was also highlighted at the UN Special Session on
is the framework of UNEP´s global water assessment strategy and will
the Environment (UNGASS) in 1997, where commitments were
enable us to record and report on critical water resources for the planet for
made regarding the work of the UN Commission on Sustainable
consideration of sustainable development management practices as part of
Development (UNCSD) on freshwater in 1998 and seas in 1999. Also in
our responsibilities under Agenda 21 agreements of the Rio conference".
1997, two international Declarations, the Potomac Declaration: Towards
enhanced ocean security into the third millennium, and the Stockholm
The importance of the GIWA has been further underpinned by the UN
Statement on inter action of land activities, freshwater and enclosed
Millennium Development Goals adopted by the UN General Assembly
seas, specifi cally emphasised the need for an investigation of the root
in 2000 and the Declaration from the World Summit on Sustainable
ii
REGIONAL ASSESSMENTS
Development in 2002. The development goals aimed to halve the
International waters and transboundary issues
proportion of people without access to safe drinking water and basic
The term "international waters", as used for the purposes of the GEF Operational Strategy,
sanitation by the year 2015 (United Nations Millennium Declaration
includes the oceans, large marine ecosystems, enclosed or semi-enclosed seas and estuaries, as
well as rivers, lakes, groundwater systems, and wetlands with transboundary drainage basins
2000). The WSSD also calls for integrated management of land, water and
or common borders. The water-related ecosystems associated with these waters are considered
living resources (WSSD 2002) and, by 2010, the Reykjavik Declaration on
integral parts of the systems.
The term "transboundary issues" is used to describe the threats to the aquatic environment
Responsible Fisheries in the Marine Ecosystem should be implemented
linked to globalisation, international trade, demographic changes and technological advancement,
by all countries that are party to the declaration (FAO 2001).
threats that are additional to those created through transboundary movement of water. Single
country policies and actions are inadequate in order to cope with these challenges and this makes
them transboundary in nature.
The international waters area includes numerous international conventions, treaties, and
agreements. The architecture of marine agreements is especially complex, and a large number
The conceptual framework
of bilateral and multilateral agreements exist for transboundary freshwater basins. Related
conventions and agreements in other areas increase the complexity. These initiatives provide
and objectives
a new opportunity for cooperating nations to link many different programmes and instruments
into regional comprehensive approaches to address international waters.
Considering the general decline in the condition of the world's aquatic
the large-scale deforestation of mangroves for ponds (Primavera 1997).
resources and the internationally recognised need for a globally
Within the GIWA, these "non-hydrological" factors constitute as large
coherent assessment of transboundary waters, the primary objectives
a transboundary infl uence as more traditionally recognised problems,
of the GIWA are:
such as the construction of dams that regulate the fl ow of water into
To provide a prioritising mechanism that allows the GEF to focus
a neighbouring country, and are considered equally important. In
their resources so that they are used in the most cost eff ective
addition, the GIWA recognises the importance of hydrological units that
manner to achieve signifi cant environmental benefi ts, at national,
would not normally be considered transboundary but exert a signifi cant
regional and global levels; and
infl uence on transboundary waters, such as the Yangtze River in China
To highlight areas in which governments can develop and
which discharges into the East China Sea (Daoji & Daler 2004) and the
implement strategic policies to reduce environmental degradation
Volga River in Russia which is largely responsible for the condition of
and improve the management of aquatic resources.
the Caspian Sea (Barannik et al. 2004). Furthermore, the GIWA is a truly
regional assessment that has incorporated data from a wide range of
In order to meet these objectives and address some of the current
sources and included expert knowledge and information from a wide
inadequacies in international aquatic resources management, the GIWA
range of sectors and from each country in the region. Therefore, the
has incorporated four essential elements into its design:
transboundary concept adopted by the GIWA extends to include
A broad transboundary approach that generates a truly regional
impacts caused by globalisation, international trade, demographic
perspective through the incorporation of expertise and existing
changes and technological advances and recognises the need for
information from all nations in the region and the assessment of
international cooperation to address them.
all factors that infl uence the aquatic resources of the region;
A drainage basin approach integrating freshwater and marine
systems;
A multidisciplinary approach integrating environmental and socio-
The organisational structure and
economic information and expertise; and
implementation of the GIWA
A coherent assessment that enables global comparison of the
results.
The scale of the assessment
Initially, the scope of the GIWA was confi ned to transboundary waters
The GIWA builds on previous assessments implemented within the GEF
in areas that included countries eligible to receive funds from the GEF.
International Waters portfolio but has developed and adopted a broader
However, it was recognised that a truly global perspective would only
defi nition of transboundary waters to include factors that infl uence the
be achieved if industrialised, GEF-ineligible regions of the world were
quality and quantity of global aquatic resources. For example, due to
also assessed. Financial resources to assess the GEF-eligible countries
globalisation and international trade, the market for penaeid shrimps
were obtained primarily from the GEF (68%), the Swedish International
has widened and the prices soared. This, in turn, has encouraged
Development Cooperation Agency (Sida) (18%), and the Finnish
entrepreneurs in South East Asia to expand aquaculture resulting in
Department for International Development Cooperation (FINNIDA)
GLOBAL INTERNATIONAL WATERS ASSESSMENT
iii
1b
1c
1d
16
15
11
14
12
1a
13
17
28
10
18
25
30
9
19
23
7
22
8
31
6
24
33
20
34
26
2
5
27
50
51
32
21
36
37
41
52
4
49
53
43
54
55
65
42
3
56
42
46
42
47
62
40b
57
40a
40a
47
47
45b
59
39
45a
58
64
60
44
38
61
63
66
áGIWAá2006
1a Russian Arctic (4 LMEs)
8 Gulf of St Lawrence
17 Baltic
Sea
(LME)
26 California Current (LME)
38 Patagonian Shelf (LME)
45b Indian Ocean Islands
52 Arabian
Sea
(LME)
61 Great
Australian
Bight
1b Arctic
Greenland
(LME)
9 Newfoundland Shelf (LME)
18 North Sea (LME)
27 Gulf of California (LME)
39 Brazil Current (LME)
46 Somali Coastal
53 Bay of Bengal
62 Pacifi c Islands
1c Arctic
European/Atlantic
10 Baffi
n Bay, Labrador Sea,
19 Celtic-Biscay Shelf (LME)
28 Bering Sea (LME)
40a Northeast Brazil
Current (LME)
54 South China Sea (2 LMEs)
63 Tasman
Sea
1d Arctic North American
Canadian Archipelago
20 Iberian Coastal Sea (LME)
30 Sea of Okhotsk (LME)
Shelf (2 LMEs)
47 East
African
Rift
55 Mekong
River
64 Humboldt Current (LME)
2
Gulf of Mexico (LME)
11 Barents
Sea
(LME)
21 North Africa and
31 Oyashio Current (LME)
40b Amazon
Valley Lakes
56 Sulu-Celebes Sea (LME)
65 Eastern Equatorial
3 Caribbean
Sea
(LME)
12 Norwegian
Sea
(LME)
Nile River Basin (LME)
32 Kuroshio Current (LME)
41 Canary Current (LME)
49 Red Sea and
57 Indonesian
Seas
(LME)
Pacifi c (LME)
4 Caribbean
Islands
(LME)
13 Faroe
plateau
22 Black Sea (LME)
33 Sea of Japan (LME)
42 Guinea Current (LME)
Gulf of Aden (LME)
58 North Australian
66 Antarctic (LME)
5
Southeast Shelf (LME)
14 Iceland
Shelf
(LME)
23 Caspian
Sea
34 Yellow Sea (LME)
43 Lake Chad
50 Euphrates and
Shelf (LME)
6 Northeast Shelf (LME)
15 East Greenland Shelf (LME)
24 Aral Sea
36 East China Sea (LME)
44 Benguela Current (LME)
Tigris River Basin
59 Coral
Sea
Basin
7
Scotian Shelf (LME)
16 West Greenland Shelf (LME)
25 Gulf of Alaska (LME)
37 Hawaiian Archipelago (LME)
45a Agulhas Current (LME)
51 Jordan
60 Great Barrier Reef (LME)
Figure 1
The 66 transboundary regions assessed within the GIWA project.
(10%). Other contributions were made by Kalmar Municipality, the
Large Marine Ecocsystems (LMEs)
University of Kalmar and the Norwegian Government. The assessment of
Large Marine Ecosystems (LMEs) are regions of ocean space encompassing coastal areas from river
regions ineligible for GEF funds was conducted by various international
basins and estuaries to the seaward boundaries of continental shelves and the outer margin of the
major current systems. They are relatively large regions on the order of 200 000 km2 or greater,
and national organisations as in-kind contributions to the GIWA.
characterised by distinct: (1) bathymetry, (2) hydrography, (3) productivity, and (4) trophically
dependent populations.
The Large Marine Ecosystems strategy is a global effort for the assessment and management
In order to be consistent with the transboundary nature of many of the
of international coastal waters. It developed in direct response to a declaration at the 1992
world's aquatic resources and the focus of the GIWA, the geographical
Rio Summit. As part of the strategy, the World Conservation Union (IUCN) and National Oceanic
and Atmospheric Administration (NOAA) have joined in an action program to assist developing
units being assessed have been designed according to the watersheds
countries in planning and implementing an ecosystem-based strategy that is focused on LMEs as
of discrete hydrographic systems rather than political borders (Figure 1).
the principal assessment and management units for coastal ocean resources. The LME concept is
also adopted by GEF that recommends the use of LMEs and their contributing freshwater basins
The geographic units of the assessment were determined during the
as the geographic area for integrating changes in sectoral economic activities.
preparatory phase of the project and resulted in the division of the
world into 66 regions defi ned by the entire area of one or more
The global network
catchments areas that drains into a single designated marine system.
In each of the 66 regions, the assessment is conducted by a team of
These marine systems often correspond to Large Marine Ecosystems
local experts that is headed by a Focal Point (Figure 2). The Focal Point
(LMEs) (Sherman 1994, IOC 2002).
can be an individual, institution or organisation that has been selected
on the basis of their scientifi c reputation and experience implementing
Considering the objectives of the GIWA and the elements incorporated
international assessment projects. The Focal Point is responsible
into its design, a new methodology for the implementation of the
for assembling members of the team and ensuring that it has the
assessment was developed during the initial phase of the project. The
necessary expertise and experience in a variety of environmental
methodology focuses on fi ve major environmental concerns which
and socio-economic disciplines to successfully conduct the regional
constitute the foundation of the GIWA assessment; Freshwater shortage,
assessment. The selection of team members is one of the most critical
Pollution, Habitat and community modifi cation, Overexploitation of fi sh
elements for the success of GIWA and, in order to ensure that the
and other living resources, and Global change. The GIWA methodology
most relevant information is incorporated into the assessment, team
is outlined in the following chapter.
members were selected from a wide variety of institutions such as
iv
REGIONAL ASSESSMENTS
an assessment did not exist. Therefore, in order to implement the GIWA,
Steering Group
a new methodology that adopted a multidisciplinary, multi-sectoral,
multi-national approach was developed and is now available for the
implementation of future international assessments of aquatic resources.
GIWA Partners
IGOs, NGOs,
Core
Thematic
The GIWA is comprised of a logical sequence of four integrated
Scientific institutions,
Team
Task Teams
private sector, etc
components. The fi rst stage of the GIWA is called Scaling and is a
66 Regional
process by which the geographic area examined in the assessment is
Focal Points
defi ned and all the transboundary waters within that area are identifi ed.
and Teams
Once the geographic scale of the assessment has been defi ned, the
Figure 2
The organisation of the GIWA project.
assessment teams conduct a process known as Scoping in which the
magnitude of environmental and associated socio-economic impacts
universities, research institutes, government agencies, and the private
of Freshwater shortage, Pollution, Habitat and community modifi cation,
sector. In addition, in order to ensure that the assessment produces a
Unsustainable exploitation of fi sh and other living resources, and Global
truly regional perspective, the teams should include representatives
change is assessed in order to identify and prioritise the concerns
from each country that shares the region.
that require the most urgent intervention. The assessment of these
predefi ned concerns incorporates the best available information and
In total, more than 1 000 experts have contributed to the implementation
the knowledge and experience of the multidisciplinary, multi-national
of the GIWA illustrating that the GIWA is a participatory exercise that
assessment teams formed in each region. Once the priority concerns
relies on regional expertise. This participatory approach is essential
have been identifi ed, the root causes of these concerns are identifi ed
because it instils a sense of local ownership of the project, which
during the third component of the GIWA, Causal chain analysis. The root
ensures the credibility of the fi ndings and moreover, it has created a
causes are determined through a sequential process that identifi es, in
global network of experts and institutions that can collaborate and
turn, the most signifi cant immediate causes followed by the economic
exchange experiences and expertise to help mitigate the continued
sectors that are primarily responsible for the immediate causes and
degradation of the world's aquatic resources.
fi nally, the societal root causes. At each stage in the Causal chain
analysis, the most signifi cant contributors are identifi ed through an
analysis of the best available information which is augmented by the
expertise of the assessment team. The fi nal component of the GIWA is
GIWA Regional reports
the development of Policy options that focus on mitigating the impacts
of the root causes identifi ed by the Causal chain analysis.
The GIWA was established in response to growing concern among the
general public regarding the quality of the world's aquatic resources
The results of the GIWA assessment in each region are reported in
and the recognition of governments and the international community
regional reports that are published by UNEP. These reports are designed
concerning the absence of a globally coherent international waters
to provide a brief physical and socio-economic description of the
assessment. However, because a holistic, region-by-region, assessment
most important features of the region against which the results of the
of the condition of the world's transboundary water resources had never
assessment can be cast. The remaining sections of the report present
been undertaken, a methodology guiding the implementation of such
the results of each stage of the assessment in an easily digestible form.
Each regional report is reviewed by at least two independent external
UNEP Water Policy and Strategy
reviewers in order to ensure the scientifi c validity and applicability of
The primary goals of the UNEP water policy and strategy are:
each report. The 66 regional assessments of the GIWA will serve UNEP
(a) Achieving greater global understanding of freshwater, coastal and marine environments by
as an essential complement to the UNEP Water Policy and Strategy and
conducting environmental assessments in priority areas;
(b) Raising awareness of the importance and consequences of unsustainable water use;
UNEP's activities in the hydrosphere.
(c) Supporting the efforts of Governments in the preparation and implementation of integrated
management of freshwater systems and their related coastal and marine environments;
(d) Providing support for the preparation of integrated management plans and programmes for
aquatic environmental hot spots, based on the assessment results;
Global International Waters Assessment
(e) Promoting the application by stakeholders of precautionary, preventive and anticipatory
approaches.
GLOBAL INTERNATIONAL WATERS ASSESSMENT
v
References:
AMAP (1998). Assessment Report: Arctic Pollution Issues. Arctic
Monitoring and Assessment Programme (AMAP), Oslo, Norway.
Barannik, V., Borysova, O. and Stolberg, F. (2004). The Caspian Sea Region:
Environmental Change. Ambio, 33:45-51.
Brinson, M.M. and Malvárez, A.I. (2002). Temperate freshwater wetlands:
types, status, and threats. Environmental Conservation, 29:115-133.
Daoji, L. and Daler, D. (2004). Ocean Pollution from Land-based Sources:
East China Sea, China. Ambio, 33:98-106.
FAO (2001). Reykjavik conference on responsible fi sheries in the marine
ecosystem. Iceland, 1-4 October 2001.
IOC (2002). IOC-IUCN-NOAA Consultative Meeting on Large Marine
Ecosystems (LMEs). Fourth Session, 8-9 January 2002, Paris,
France.
IPCC (2001). Climate Change 2001: The Scientifi c Basis. Contribution
of Working Group I to the Third Assessment Report of the
Intergovernmental Panel on Climate Change. In: Houghton,
J.T., Ding, Y., Griggs, D.J., Noguer, M., van der Linden, P.J., Dai, X.,
Maskell, K. and Johnson, C.A. (eds). Cambridge University Press,
Cambridge, United Kingdom and New York, NY, USA.
Kennish, M.J. (2002). Environmental threats and environmental future of
estuaries. Environmental Conservation, 29:78-107.
Myers, R.A. and Worm, B. (2003). Rapid worldwide depletion of predatory
fi sh communities. Nature, 423:280-283.
Primavera, J.H. (1997) Socio-economic impacts of shrimp culture.
Aquaculture Research, 28:815-827.
Sherman, K. (1994). Sustainability, biomass yields, and health of coastal
ecosystems: an ecological perspective. Marine Ecology Progress
Series, 112:277-301.
United Nations conference on the human environment (1972). Report
available on-line at http://www.unep.org
United Nations Millennium Declaration (2000). The Millennium
Assembly of the United Nations, New York.
WHO-UNICEF (2002). Global Water Supply and Sanitation Assessment:
2000 Report.
WSSD (2002). World Summit on Sustainable Development.
Johannesburg Summit 2002. Key Outcomes of the Summit,
UN Department of Public Information, New York.
vi
REGIONAL ASSESSMENTS
The GIWA methodology
The specifi c objectives of the GIWA were to conduct a holistic and globally
The assessment integrates environmental and socio-economic data
comparable assessment of the world's transboundary aquatic resources
from each country in the region to determine the severity of the
that incorporated both environmental and socio-economic factors
impacts of each of the fi ve concerns and their constituent issues on
and recognised the inextricable links between freshwater and marine
the entire region. The integration of this information was facilitated by
environments, in order to enable the GEF to focus their resources and to
implementing the assessment during two participatory workshops
provide guidance and advice to governments and decision makers. The
that typically involved 10 to 15 environmental and socio-economic
coalition of all these elements into a single coherent methodology that
experts from each country in the region. During these workshops, the
produces an assessment that achieves each of these objectives had not
regional teams performed preliminary analyses based on the collective
previously been done and posed a signifi cant challenge.
knowledge and experience of these local experts. The results of these
analyses were substantiated with the best available information to be
The integration of each of these elements into the GIWA methodology
presented in a regional report.
was achieved through an iterative process guided by a specially
Table 1 Pre-defi ned GIWA concerns and their constituent issues
convened Methods task team that was comprised of a number of
addressed within the assessment.
international assessment and water experts. Before the fi nal version
of the methodology was adopted, preliminary versions underwent
Environmental issues
Major concerns
an extensive external peer review and were subjected to preliminary
1. Modification of stream flow
testing in selected regions. Advice obtained from the Methods task
2. Pollution of existing supplies
I Freshwater shortage
3. Changes in the water table
team and other international experts and the lessons learnt from
preliminary testing were incorporated into the fi nal version that was
4. Microbiological
5. Eutrophication
used to conduct each of the GIWA regional assessments.
6. Chemical
7. Suspended
solids
II Pollution
8. Solid wastes
Considering the enormous diff erences between regions in terms of the
9. Thermal
10. Radionuclide
quality, quantity and availability of data, socio-economic setting and
11. Spills
environmental conditions, the achievement of global comparability
12. Loss of ecosystems
required an innovative approach. This was facilitated by focusing
III Habitat and community
13. Modification of ecosystems or ecotones, including community
modification
structure and/or species composition
the assessment on the impacts of fi ve pre-defi ned concerns namely;
Freshwater shortage, Pollution, Habitat and community modifi cation,
14. Overexploitation
15. Excessive by-catch and discards
IV Unsustainable
Unsustainable exploitation of fi sh and other living resources and Global
16. Destructive fishing practices
exploitation of fish and
change, in transboundary waters. Considering the diverse range of
17. Decreased viability of stock through pollution and disease
other living resources
18. Impact on biological and genetic diversity
elements encompassed by each concern, assessing the magnitude of
the impacts caused by these concerns was facilitated by evaluating the
19. Changes in hydrological cycle
20. Sea level change
V Global change
impacts of 22 specifi c issues that were grouped within these concerns
21. Increased uv-b radiation as a result of ozone depletion
22. Changes in ocean CO2 source/sink function
(see Table 1).
THE GIWA METHODOLOGY
vii
political boundaries but were instead, generally defi ned by a large but
T
r
ansboundar
The GIWA approach
discrete drainage basin that also included the coastal marine waters into
which the basin discharges. In many cases, the marine areas examined
1
Scaling
st
W
orkshop
Detailed
during the assessment coincided with the Large Marine Ecosystems
y
D
(LMEs) defi ned by the US National Atmospheric and Oceanographic
iagnostic
A
ssessment
Scoping
Administration (NOAA). As a consequence, scaling should be a
relatively straight-forward task that involves the inspection of the
Analy
boundaries that were proposed for the region during the preparatory
Causal Chain
2 nd
Analysis
sis
phase of GIWA to ensure that they are appropriate and that there are
W
orkshop
no important overlaps or gaps with neighbouring regions. When the
Policy Option
proposed boundaries were found to be inadequate, the boundaries of
Analysis
the region were revised according to the recommendations of experts
from both within the region and from adjacent regions so as to ensure
that any changes did not result in the exclusion of areas from the GIWA.
Once the regional boundary was defi ned, regional teams identifi ed all
SAP
the transboundary elements of the aquatic environment within the
SAP
region and determined if these elements could be assessed as a single
Figure 1
Illustration of the relationship between the GIWA
coherent aquatic system or if there were two or more independent
approach and other projects implemented within the
systems that should be assessed separately.
GEF International Waters (IW) portfolio.
The GIWA is a logical contiguous process that defi nes the geographic
Scoping Assessing the GIWA concerns
region to be assessed, identifi es and prioritises particularly problems
Scoping is an assessment of the severity of environmental and socio-
based on the magnitude of their impacts on the environment and
economic impacts caused by each of the fi ve pre-defi ned GIWA concerns
human societies in the region, determines the root causes of those
and their constituent issues (Table 1). It is not designed to provide an
problems and, fi nally, assesses various policy options that addresses
exhaustive review of water-related problems that exist within each region,
those root causes in order to reverse negative trends in the condition
but rather it is a mechanism to identify the most urgent problems in the
of the aquatic environment. These four steps, referred to as Scaling,
region and prioritise those for remedial actions. The priorities determined
Scoping, Causal chain analysis and Policy options analysis, are
by Scoping are therefore one of the main outputs of the GIWA project.
summarised below and are described in their entirety in two volumes:
GIWA Methodology Stage 1: Scaling and Scoping; and GIWA Methodology:
Focusing the assessment on pre-defi ned concerns and issues ensured
Detailed Assessment, Causal Chain Analysis and Policy Options Analysis.
the comparability of the results between diff erent regions. In addition, to
Generally, the components of the GIWA methodology are aligned
ensure the long-term applicability of the options that are developed to
with the framework adopted by the GEF for Transboundary Diagnostic
mitigate these problems, Scoping not only assesses the current impacts
Analyses (TDAs) and Strategic Action Programmes (SAPs) (Figure 1) and
of these concerns and issues but also the probable future impacts
assume a broad spectrum of transboundary infl uences in addition to
according to the "most likely scenario" which considered demographic,
those associated with the physical movement of water across national
economic, technological and other relevant changes that will potentially
borders.
infl uence the aquatic environment within the region by 2020.
Scaling Defining the geographic extent
The magnitude of the impacts caused by each issue on the
of the region
environment and socio-economic indicators was assessed over the
Scaling is the fi rst stage of the assessment and is the process by which
entire region using the best available information from a wide range of
the geographic scale of the assessment is defi ned. In order to facilitate
sources and the knowledge and experience of the each of the experts
the implementation of the GIWA, the globe was divided during the
comprising the regional team. In order to enhance the comparability
design phase of the project into 66 contiguous regions. Considering the
of the assessment between diff erent regions and remove biases
transboundary nature of many aquatic resources and the transboundary
in the assessment caused by diff erent perceptions of and ways to
focus of the GIWA, the boundaries of the regions did not comply with
communicate the severity of impacts caused by particular issues, the
viii
REGIONAL ASSESSMENTS
results were distilled and reported as standardised scores according to
Table 2
Example of environmental impact assessment of
Freshwater shortage.
the following four point scale:
Weight
0 = no known impact
Environmental
Environmental issues
Score
Weight %
averaged
concerns
1 = slight impact
score
2 = moderate impact
1. Modification of stream flow
1
20
Freshwater shortage
1.50
3 = severe impact
2. Pollution of existing supplies
2
50
The attributes of each score for each issue were described by a detailed
3. Changes in the water table
1
30
set of pre-defi ned criteria that were used to guide experts in reporting
Table 3
Example of Health impacts assessment linked to one of
the results of the assessment. For example, the criterion for assigning
the GIWA concerns.
a score of 3 to the issue Loss of ecosystems or ecotones is: "Permanent
Criteria for Health impacts
Raw score
Score
Weight %
destruction of at least one habitat is occurring such as to have reduced their
Very small
Very large
surface area by >30% during the last 2-3 decades". The full list of criteria is
Number of people affected
2
50
0 1 2 3
presented at the end of the chapter, Table 5a-e. Although the scoring
Minimum
Severe
Degree of severity
2
30
0 1 2 3
inevitably includes an arbitrary component, the use of predefi ned
Occasion/Short
Continuous
Frequency/Duration
2
20
0 1 2 3
criteria facilitates comparison of impacts on a global scale and also
Weight average score for Health impacts
2
encouraged consensus of opinion among experts.
The trade-off associated with assessing the impacts of each concern
After all 22 issues and associated socio-economic impacts have
and their constituent issues at the scale of the entire region is that spatial
been scored, weighted and averaged, the magnitude of likely future
resolution was sometimes low. Although the assessment provides a
changes in the environmental and socio-economic impacts of each
score indicating the severity of impacts of a particular issue or concern
of the fi ve concerns on the entire region is assessed according to the
on the entire region, it does not mean that the entire region suff ers
most likely scenario which describes the demographic, economic,
the impacts of that problem. For example, eutrophication could be
technological and other relevant changes that might infl uence the
identifi ed as a severe problem in a region, but this does not imply that all
aquatic environment within the region by 2020.
waters in the region suff er from severe eutrophication. It simply means
that when the degree of eutrophication, the size of the area aff ected,
In order to prioritise among GIWA concerns within the region and
the socio-economic impacts and the number of people aff ected is
identify those that will be subjected to causal chain and policy options
considered, the magnitude of the overall impacts meets the criteria
analysis in the subsequent stages of the GIWA, the present and future
defi ning a severe problem and that a regional action should be initiated
scores of the environmental and socio-economic impacts of each
in order to mitigate the impacts of the problem.
concern are tabulated and an overall score calculated. In the example
presented in Table 4, the scoping assessment indicated that concern III,
When each issue has been scored, it was weighted according to the relative
Habitat and community modifi cation, was the priority concern in this
contribution it made to the overall environmental impacts of the concern
region. The outcome of this mathematic process was reconciled against
and a weighted average score for each of the fi ve concerns was calculated
the knowledge of experts and the best available information in order
(Table 2). Of course, if each issue was deemed to make equal contributions,
to ensure the validity of the conclusion.
then the score describing the overall impacts of the concern was simply the
arithmetic mean of the scores allocated to each issue within the concern.
In some cases however, this process and the subsequent participatory
In addition, the socio-economic impacts of each of the fi ve major
discussion did not yield consensus among the regional experts
concerns were assessed for the entire region. The socio-economic
regarding the ranking of priorities. As a consequence, further analysis
impacts were grouped into three categories; Economic impacts,
was required. In such cases, expert teams continued by assessing the
Health impacts and Other social and community impacts (Table 3). For
relative importance of present and potential future impacts and assign
each category, an evaluation of the size, degree and frequency of the
weights to each. Afterwards, the teams assign weights indicating the
impact was performed and, once completed, a weighted average score
relative contribution made by environmental and socio-economic
describing the overall socio-economic impacts of each concern was
factors to the overall impacts of the concern. The weighted average
calculated in the same manner as the overall environmental score.
score for each concern is then recalculated taking into account
THE GIWA METHODOLOGY
ix
Table 4
Example of comparative environmental and socio-economic impacts of each major concern, presently and likely in year 2020.
Types of impacts
Environmental score
Economic score
Human health score
Social and community score
Concern
Overall score
Present (a)
Future (b)
Present (c)
Future (d)
Present (e)
Future (f)
Present (g)
Future (h)
Freshwater shortage
1.3
2.3
2.7
2.8
2.6
3.0
1.8
2.2
2.3
Pollution
1.5
2.0
2.0
2.3
1.8
2.3
2.0
2.3
2.0
Habitat and community
2.0
3.0
2.4
3.0
2.4
2.8
2.3
2.7
2.6
modification
Unsustainable exploitation of fish
1.8
2.2
2.0
2.1
2.0
2.1
2.4
2.5
2.1
and other living resources
Global change
0.8
1.0
1.5
1.7
1.5
1.5
1.0
1.0
1.2
the relative contributions of both present and future impacts and
should be regarded as a framework to guide the analysis, rather than
environmental and socio-economic factors. The outcome of these
as a set of detailed instructions. Secondly, in an ideal setting, a causal
additional analyses was subjected to further discussion to identify
chain would be produced by a multidisciplinary group of specialists
overall priorities for the region.
that would statistically examine each successive cause and study its
links to the problem and to other causes. However, this approach (even
Finally, the assessment recognises that each of the fi ve GIWA concerns
if feasible) would use far more resources and time than those available
are not discrete but often interact. For example, pollution can destroy
to GIWA1. For this reason, it has been necessary to develop a relatively
aquatic habitats that are essential for fi sh reproduction which, in turn,
simple and practical analytical model for gathering information to
can cause declines in fi sh stocks and subsequent overexploitation. Once
assemble meaningful causal chains.
teams have ranked each of the concerns and determined the priorities
for the region, the links between the concerns are highlighted in order
Conceptual model
to identify places where strategic interventions could be applied to
A causal chain is a series of statements that link the causes of a problem
yield the greatest benefi ts for the environment and human societies
with its eff ects. Recognising the great diversity of local settings and the
in the region.
resulting diffi
culty in developing broadly applicable policy strategies,
the GIWA CCA focuses on a particular system and then only on those
Causal chain analysis
issues that were prioritised during the scoping assessment. The
Causal Chain Analysis (CCA) traces the cause-eff ect pathways from the
starting point of a particular causal chain is one of the issues selected
socio-economic and environmental impacts back to their root causes.
during the Scaling and Scoping stages and its related environmental
The GIWA CCA aims to identify the most important causes of each
and socio-economic impacts. The next element in the GIWA chain is
concern prioritised during the scoping assessment in order to direct
the immediate cause; defi ned as the physical, biological or chemical
policy measures at the most appropriate target in order to prevent
variable that produces the GIWA issue. For example, for the issue of
further degradation of the regional aquatic environment.
eutrophication the immediate causes may be, inter alia:
Enhanced nutrient inputs;
Root causes are not always easy to identify because they are often
Increased
recycling/mobilisation;
spatially or temporally separated from the actual problems they
Trapping of nutrients (e.g. in river impoundments);
cause. The GIWA CCA was developed to help identify and understand
Run-off and stormwaters
the root causes of environmental and socio-economic problems
in international waters and is conducted by identifying the human
Once the relevant immediate cause(s) for the particular system has
activities that cause the problem and then the factors that determine
(have) been identifi ed, the sectors of human activity that contribute
the ways in which these activities are undertaken. However, because
most signifi cantly to the immediate cause have to be determined.
there is no universal theory describing how root causes interact to
Assuming that the most important immediate cause in our example
create natural resource management problems and due to the great
had been increased nutrient concentrations, then it is logical that the
variation of local circumstances under which the methodology will
most likely sources of those nutrients would be the agricultural, urban
be applied, the GIWA CCA is not a rigidly structured assessment but
or industrial sectors. After identifying the sectors that are primarily
1 This does not mean that the methodology ignores statistical or quantitative studies; as has already been pointed out, the available evidence that justifies the assumption of causal links should
be provided in the assessment.
x
REGIONAL ASSESSMENTS
responsible for the immediate causes, the root causes acting on those
The policy options recommended by the GIWA are only contributions
sectors must be determined. For example, if agriculture was found to
to the larger policy process and, as such, the GIWA methodology
be primarily responsible for the increased nutrient concentrations, the
developed to test the performance of various options under the
root causes could potentially be:
diff erent circumstances has been kept simple and broadly applicable.
Economic (e.g. subsidies to fertilisers and agricultural products);
Legal (e.g. inadequate regulation);
Global International Waters Assessment
Failures in governance (e.g. poor enforcement); or
Technology or knowledge related (e.g. lack of aff ordable substitutes
for fertilisers or lack of knowledge as to their application).
Once the most relevant root causes have been identifi ed, an
explanation, which includes available data and information, of how
they are responsible for the primary environmental and socio-economic
problems in the region should be provided.
Policy option analysis
Despite considerable eff ort of many Governments and other
organisations to address transboundary water problems, the evidence
indicates that there is still much to be done in this endeavour. An
important characteristic of GIWA's Policy Option Analysis (POA) is that
its recommendations are fi rmly based on a better understanding of
the root causes of the problems. Freshwater scarcity, water pollution,
overexploitation of living resources and habitat destruction are very
complex phenomena. Policy options that are grounded on a better
understanding of these phenomena will contribute to create more
eff ective societal responses to the extremely complex water related
transboundary problems. The core of POA in the assessment consists
of two tasks:
Construct policy options
Policy options are simply diff erent courses of action, which are not
always mutually exclusive, to solve or mitigate environmental and
socio-economic problems in the region. Although a multitude of
diff erent policy options could be constructed to address each root
cause identifi ed in the CCA, only those few policy options that have
the greatest likelihood of success were analysed in the GIWA.
Select and apply the criteria on which the policy options will be
evaluated
Although there are many criteria that could be used to evaluate any
policy option, GIWA focuses on:
Eff ectiveness (certainty of result)
Effi
ciency (maximisation of net benefi ts)
Equity (fairness of distributional impacts)
Practical criteria (political acceptability, implementation feasibility).
THE GIWA METHODOLOGY
xi
Table 5a: Scoring criteria for environmental impacts of Freshwater shortage
Issue
Score 0 = no known impact
Score 1 = slight impact
Score 2 = moderate impact
Score 3 = severe impact
Issue 1: Modification
No evidence of modification of stream
There is a measurably changing trend in
Significant downward or upward trend
Annual discharge of a river altered by more
of stream flow
flow.
annual river discharge at gauging stations
(more than 20% of the long term mean) in
than 50% of long term mean; or
"An increase or decrease
in a major river or tributary (basin >
annual discharges in a major river or tributary Loss of >50% of riparian or deltaic
in the discharge of
40 000 km2); or
draining a basin of >250 000 km2; or
wetlands over a period of not less than
streams and rivers
There is a measurable decrease in the area
Loss of >20% of flood plain or deltaic
40 years (through causes other than
as a result of human
of wetlands (other than as a consequence
wetlands through causes other than
conversion or artificial embankment); or
interventions on a local/
of conversion or embankment
conversion or artificial embankments; or
Significant increased siltation or erosion
regional scale (see Issue
construction); or
Significant loss of riparian vegetation (e.g.
due to changing in flow regime (other than
19 for flow alterations
There is a measurable change in the
trees, flood plain vegetation); or
normal fluctuations in flood plain rivers);
resulting from global
interannual mean salinity of estuaries or
Significant saline intrusion into previously
or
change) over the last 3-4
coastal lagoons and/or change in the mean
freshwater rivers or lagoons.
Loss of one or more anadromous or
decades."
position of estuarine salt wedge or mixing
catadromous fish species for reasons
zone; or
other than physical barriers to migration,
Change in the occurrence of exceptional
pollution or overfishing.
discharges (e.g. due to upstream
damming.
Issue 2: Pollution of
No evidence of pollution of surface and
Any monitored water in the region does
Water supplies does not meet WHO or
River draining more than 10% of the basin
existing supplies
ground waters.
not meet WHO or national drinking water
national drinking water standards in more
have suffered polysaprobic conditions, no
"Pollution of surface
criteria, other than for natural reasons; or
than 30% of the region; or
longer support fish, or have suffered severe
and ground fresh waters
There have been reports of one or more
There are one or more reports of fish kills
oxygen depletion
supplies as a result of
fish kills in the system due to pollution
due to pollution in any river draining a
Severe pollution of other sources of
point or diffuse sources"
within the past five years.
basin of >250 000 km2 .
freshwater (e.g. groundwater)
Issue 3: Changes in the No evidence that abstraction of water from Several wells have been deepened because Clear evidence of declining base flow in
Aquifers are suffering salinisation over
water table
aquifers exceeds natural replenishment.
of excessive aquifer draw-down; or
rivers in semi-arid areas; or
regional scale; or
"Changes in aquifers
Several springs have dried up; or
Loss of plant species in the past decade,
Perennial springs have dried up over
as a direct or indirect
Several wells show some salinisation.
that depend on the presence of ground
regionally significant areas; or
consequence of human
water; or
Some aquifers have become exhausted
activity"
Wells have been deepened over areas of
hundreds of km2;or
Salinisation over significant areas of the
region.
Table 5b: Scoring criteria for environmental impacts of Pollution
Issue
Score 0 = no known impact
Score 1 = slight impact
Score 2 = moderate impact
Score 3 = severe impact
Issue 4:
Normal incidence of bacterial related
There is minor increase in incidence of
Public health authorities aware of marked
There are large closure areas or very
Microbiological
gastroenteric disorders in fisheries product
bacterial related gastroenteric disorders
increase in the incidence of bacterial
restrictive advisories affecting the
pollution
consumers and no fisheries closures or
in fisheries product consumers but no
related gastroenteric disorders in fisheries
marketability of fisheries products; or
"The adverse effects of
advisories.
fisheries closures or advisories.
product consumers; or
There exists widespread public or tourist
microbial constituents of
There are limited area closures or
awareness of hazards resulting in
human sewage released
advisories reducing the exploitation or
major reductions in the exploitation or
to water bodies."
marketability of fisheries products.
marketability of fisheries products.
Issue 5:
No visible effects on the abundance and
Increased abundance of epiphytic algae; or
Increased filamentous algal production
High frequency (>1 event per year), or
Eutrophication
distributions of natural living resource
A statistically significant trend in
resulting in algal mats; or
intensity, or large areas of periodic hypoxic
"Artificially enhanced
distributions in the area; and
decreased water transparency associated
Medium frequency (up to once per year)
conditions, or high frequencies of fish and
primary productivity in
No increased frequency of hypoxia1 or
with algal production as compared with
of large-scale hypoxia and/or fish and
zoobenthos mortality events or harmful
receiving water basins
fish mortality events or harmful algal
long-term (>20 year) data sets; or
zoobenthos mortality events and/or
algal blooms; or
related to the increased
blooms associated with enhanced primary
Measurable shallowing of the depth range
harmful algal blooms.
Significant changes in the littoral
availability or supply
production; and
of macrophytes.
community; or
of nutrients, including
No evidence of periodically reduced
Presence of hydrogen sulphide in
cultural eutrophication
dissolved oxygen or fish and zoobenthos
historically well oxygenated areas.
in lakes."
mortality; and
No evident abnormality in the frequency of
algal blooms.
xii
REGIONAL ASSESSMENTS
Issue 6: Chemical
No known or historical levels of chemical
Some chemical contaminants are
Some chemical contaminants are above
Chemical contaminants are above
pollution
contaminants except background levels of
detectable but below threshold limits
threshold limits defined for the country or
threshold limits defined for the country or
"The adverse effects of
naturally occurring substances; and
defined for the country or region; or
region; or
region; and
chemical contaminants
No fisheries closures or advisories due to
Restricted area advisories regarding
Large area advisories by public health
Public health and public awareness of
released to standing or
chemical pollution; and
chemical contamination of fisheries
authorities concerning fisheries product
fisheries contamination problems with
marine water bodies
No incidence of fisheries product tainting;
products.
contamination but without associated
associated reductions in the marketability
as a result of human
and
catch restrictions or closures; or
of such products either through the
activities. Chemical
No unusual fish mortality events.
If there is no available data use the following
High mortalities of aquatic species near
imposition of limited advisories or by area
contaminants are
criteria:
outfalls.
closures of fisheries; or
here defined as
If there is no available data use the following
Some use of pesticides in small areas; or
Large-scale mortalities of aquatic species.
compounds that are
criteria:
Presence of small sources of dioxins or
If there is no available data use the following
toxic or persistent or
No use of pesticides; and
furans (e.g., small incineration plants or
criteria:
If there is no available data use the following
bioaccumulating."
No sources of dioxins and furans; and
bleached kraft/pulp mills using chlorine);
Large-scale use of pesticides in agriculture
criteria:
No regional use of PCBs; and
or
and forestry; or
Indications of health effects resulting
No bleached kraft pulp mills using chlorine Some previous and existing use of PCBs
Presence of major sources of dioxins or
from use of pesticides; or
bleaching; and
and limited amounts of PCB-containing
furans such as large municipal or industrial Known emissions of dioxins or furans from
No use or sources of other contaminants.
wastes but not in amounts invoking local
incinerators or large bleached kraft pulp
incinerators or chlorine bleaching of pulp;
concerns; or
mills; or
or
Presence of other contaminants.
Considerable quantities of waste PCBs in
Known contamination of the environment
the area with inadequate regulation or has
or foodstuffs by PCBs; or
invoked some public concerns; or
Known contamination of the environment
Presence of considerable quantities of
or foodstuffs by other contaminants.
other contaminants.
Issue 7: Suspended
No visible reduction in water transparency; Evidently increased or reduced turbidity
Markedly increased or reduced turbidity
Major changes in turbidity over wide or
solids
and
in streams and/or receiving riverine and
in small areas of streams and/or receiving
ecologically significant areas resulting
"The adverse effects of
No evidence of turbidity plumes or
marine environments but without major
riverine and marine environments; or
in markedly changed biodiversity or
modified rates of release
increased siltation; and
changes in associated sedimentation or
Extensive evidence of changes in
mortality in benthic species due to
of suspended particulate No evidence of progressive riverbank,
erosion rates, mortality or diversity of flora
sedimentation or erosion rates; or
excessive sedimentation with or without
matter to water bodies
beach, other coastal or deltaic erosion.
and fauna; or
Changes in benthic or pelagic biodiversity
concomitant changes in the nature of
resulting from human
Some evidence of changes in benthic or
in areas due to sediment blanketing or
deposited sediments (i.e., grain-size
activities"
pelagic biodiversity in some areas due
increased turbidity.
composition/redox); or
to sediment blanketing or increased
Major change in pelagic biodiversity or
turbidity.
mortality due to excessive turbidity.
Issue 8: Solid wastes
No noticeable interference with trawling
Some evidence of marine-derived litter on
Widespread litter on beaches giving rise to Incidence of litter on beaches sufficient
"Adverse effects
activities; and
beaches; or
public concerns regarding the recreational
to deter the public from recreational
associated with the
No noticeable interference with the
Occasional recovery of solid wastes
use of beaches; or
activities; or
introduction of solid
recreational use of beaches due to litter;
through trawling activities; but
High frequencies of benthic litter recovery
Trawling activities untenable because of
waste materials into
and
Without noticeable interference with
and interference with trawling activities;
benthic litter and gear entanglement; or
water bodies or their
No reported entanglement of aquatic
trawling and recreational activities in
or
Widespread entanglement and/or
environs."
organisms with debris.
coastal areas.
Frequent reports of entanglement/
suffocation of aquatic species by litter.
suffocation of species by litter.
Issue 9: Thermal
No thermal discharges or evidence of
Presence of thermal discharges but
Presence of thermal discharges with large
Presence of thermal discharges with large
"The adverse effects
thermal effluent effects.
without noticeable effects beyond
mixing zones having reduced productivity
mixing zones with associated mortalities,
of the release of
the mixing zone and no significant
or altered biodiversity; or
substantially reduced productivity or
aqueous effluents at
interference with migration of species.
Evidence of reduced migration of species
noticeable changes in biodiversity; or
temperatures exceeding
due to thermal plume.
Marked reduction in the migration of
ambient temperature
species due to thermal plumes.
in the receiving water
body."
Issue 10: Radionuclide No radionuclide discharges or nuclear
Minor releases or fallout of radionuclides
Minor releases or fallout of radionuclides
Substantial releases or fallout of
"The adverse effects of
activities in the region.
but with well regulated or well-managed
under poorly regulated conditions that do
radionuclides resulting in excessive
the release of radioactive
conditions complying with the Basic Safety
not provide an adequate basis for public
exposures to humans or animals in relation
contaminants and
Standards.
health assurance or the protection of
to those recommended under the Basic
wastes into the aquatic
aquatic organisms but without situations
Safety Standards; or
environment from
or levels likely to warrant large scale
Some indication of situations or exposures
human activities."
intervention by a national or international
warranting intervention by a national or
authority.
international authority.
Issue 11: Spills
No evidence of present or previous spills of
Some evidence of minor spills of hazardous Evidence of widespread contamination
Widespread contamination by hazardous
"The adverse effects
hazardous material; or
materials in small areas with insignificant
by hazardous or aesthetically displeasing
or aesthetically displeasing materials
of accidental episodic
No evidence of increased aquatic or avian
small-scale adverse effects one aquatic or
materials assumed to be from spillage
from frequent spills resulting in major
releases of contaminants
species mortality due to spills.
avian species.
(e.g. oil slicks) but with limited evidence of
interference with aquatic resource
and materials to the
widespread adverse effects on resources or
exploitation or coastal recreational
aquatic environment
amenities; or
amenities; or
as a result of human
Some evidence of aquatic or avian species
Significant mortality of aquatic or avian
activities."
mortality through increased presence of
species as evidenced by large numbers of
contaminated or poisoned carcasses on
contaminated carcasses on beaches.
beaches.
THE GIWA METHODOLOGY
xiii
Table 5c: Scoring criteria for environmental impacts of Habitat and community modification
Issue
Score 0 = no known impact
Score 1 = slight impact
Score 2 = moderate impact
Score 3 = severe impact
Issue 12: Loss of ecosystems or
There is no evidence of loss of
There are indications of fragmentation Permanent destruction of at least one
Permanent destruction of at least one
ecotones
ecosystems or habitats.
of at least one of the habitats.
habitat is occurring such as to have
habitat is occurring such as to have
"The complete destruction of aquatic
reduced their surface area by up to 30
reduced their surface area by >30%
habitats. For the purpose of GIWA
% during the last 2-3 decades.
during the last 2-3 decades.
methodology, recent loss will be
measured as a loss of pre-defined
habitats over the last 2-3 decades."
Issue 13: Modification of
No evidence of change in species
Evidence of change in species
Evidence of change in species
Evidence of change in species
ecosystems or ecotones, including
complement due to species extinction
complement due to species extinction
complement due to species extinction
complement due to species extinction
community structure and/or species
or introduction; and
or introduction
or introduction; and
or introduction; and
composition
No changing in ecosystem function
Evidence of change in population
Evidence of change in population
"Modification of pre-defined habitats
and services.
structure or change in functional group
structure or change in functional group
in terms of extinction of native species,
composition or structure
composition or structure; and
occurrence of introduced species and
Evidence of change in ecosystem
changing in ecosystem function and
services2.
services over the last 2-3 decades."
2 Constanza, R. et al. (1997). The value of the world ecosystem services and natural capital, Nature 387:253-260.
Table 5d: Scoring criteria for environmental impacts of Unsustainable exploitation of fish and other
living resources
Issue
Score 0 = no known impact
Score 1 = slight impact
Score 2 = moderate impact
Score 3 = severe impact
Issue 14: Overexploitation
No harvesting exists catching fish
Commercial harvesting exists but there One stock is exploited beyond MSY
More than one stock is exploited
"The capture of fish, shellfish or marine
(with commercial gear for sale or
is no evidence of over-exploitation.
(maximum sustainable yield) or is
beyond MSY or is outside safe
invertebrates at a level that exceeds the
subsistence).
outside safe biological limits.
biological limits.
maximum sustainable yield of the stock."
Issue 15: Excessive by-catch and
Current harvesting practices show no
Up to 30% of the fisheries yield (by
30-60% of the fisheries yield consists
Over 60% of the fisheries yield is
discards
evidence of excessive by-catch and/or
weight) consists of by-catch and/or
of by-catch and/or discards.
by-catch and/or discards; or
"By-catch refers to the incidental capture
discards.
discards.
Noticeable incidence of capture of
of fish or other animals that are not the
endangered species.
target of the fisheries. Discards refers
to dead fish or other animals that are
returned to the sea."
Issue 16: Destructive fishing
No evidence of habitat destruction due Habitat destruction resulting in
Habitat destruction resulting in
Habitat destruction resulting in
practices
to fisheries practices.
changes in distribution of fish or
moderate reduction of stocks or
complete collapse of a stock or far
"Fishing practices that are deemed to
shellfish stocks; or
moderate changes of the environment;
reaching changes in the environment;
produce significant harm to marine,
Trawling of any one area of the seabed
or
or
lacustrine or coastal habitats and
is occurring less than once per year.
Trawling of any one area of the seabed
Trawling of any one area of the seabed
communities."
is occurring 1-10 times per year; or
is occurring more than 10 times per
Incidental use of explosives or poisons
year; or
for fishing.
Widespread use of explosives or
poisons for fishing.
Issue 17: Decreased viability of
No evidence of increased incidence of
Increased reports of diseases without
Declining populations of one or more
Collapse of stocks as a result of
stocks through contamination and
fish or shellfish diseases.
major impacts on the stock.
species as a result of diseases or
diseases or contamination.
disease
contamination.
"Contamination or diseases of feral (wild)
stocks of fish or invertebrates that are a
direct or indirect consequence of human
action."
Issue 18: Impact on biological and
No evidence of deliberate or accidental Alien species introduced intentionally
Measurable decline in the population
Extinction of native species or local
genetic diversity
introductions of alien species; and
or accidentally without major changes
of native species or local stocks as a
stocks as a result of introductions
"Changes in genetic and species diversity No evidence of deliberate or accidental
in the community structure; or
result of introductions (intentional or
(intentional or accidental); or
of aquatic environments resulting from
introductions of alien stocks; and
Alien stocks introduced intentionally
accidental); or
Major changes (>20%) in the genetic
the introduction of alien or genetically
No evidence of deliberate or accidental
or accidentally without major changes Some changes in the genetic
composition of stocks (e.g. as a result
modified species as an intentional or
introductions of genetically modified
in the community structure; or
composition of stocks (e.g. as a result
of escapes from aquaculture replacing
unintentional result of human activities
species.
Genetically modified species
of escapes from aquaculture replacing
the wild stock).
including aquaculture and restocking."
introduced intentionally or
the wild stock).
accidentally without major changes in
the community structure.
xiv
REGIONAL ASSESSMENTS
Table 5e: Scoring criteria for environmental impacts of Global change
Issue
Score 0 = no known impact
Score 1 = slight impact
Score 2 = moderate impact
Score 3 = severe impact
Issue 19: Changes in hydrological
No evidence of changes in hydrological Change in hydrological cycles due
Significant trend in changing
Loss of an entire habitat through
cycle and ocean circulation
cycle and ocean/coastal current due to
to global change causing changes
terrestrial or sea ice cover (by
desiccation or submergence as a result
"Changes in the local/regional water
global change.
in the distribution and density of
comparison with a long-term time
of global change; or
balance and changes in ocean and coastal
riparian terrestrial or aquatic plants
series) without major downstream
Change in the tree or lichen lines; or
circulation or current regime over the
without influencing overall levels of
effects on river/ocean circulation or
Major impacts on habitats or
last 2-3 decades arising from the wider
productivity; or
biological diversity; or
biodiversity as the result of increasing
problem of global change including
Some evidence of changes in ocean
Extreme events such as flood and
frequency of extreme events; or
ENSO."
or coastal currents due to global
drought are increasing; or
Changing in ocean or coastal currents
change but without a strong effect on
Aquatic productivity has been altered
or upwelling regimes such that plant
ecosystem diversity or productivity.
as a result of global phenomena such
or animal populations are unable to
as ENSO events.
recover to their historical or stable
levels; or
Significant changes in thermohaline
circulation.
Issue 20: Sea level change
No evidence of sea level change.
Some evidences of sea level change
Changed pattern of coastal erosion due Major loss of coastal land areas due to
"Changes in the last 2-3 decades in the
without major loss of populations of
to sea level rise has became evident; or
sea-level change or sea-level induced
annual/seasonal mean sea level as a
organisms.
Increase in coastal flooding events
erosion; or
result of global change."
partly attributed to sea-level rise
Major loss of coastal or intertidal
or changing prevailing atmospheric
populations due to sea-level change or
forcing such as atmospheric pressure
sea level induced erosion.
or wind field (other than storm
surges).
Issue 21: Increased UV-B radiation as No evidence of increasing effects
Some measurable effects of UV/B
Aquatic community structure is
Measured/assessed effects of UV/B
a result of ozone depletion
of UV/B radiation on marine or
radiation on behavior or appearance of
measurably altered as a consequence
irradiation are leading to massive loss
"Increased UV-B flux as a result polar
freshwater organisms.
some aquatic species without affecting
of UV/B radiation; or
of aquatic communities or a significant
ozone depletion over the last 2-3
the viability of the population.
One or more aquatic populations are
change in biological diversity.
decades."
declining.
Issue 22: Changes in ocean CO
No measurable or assessed changes
Some reasonable suspicions that
Some evidences that the impacts
Evidences that the changes in
2
source/sink function
in CO source/sink function of aquatic
current global change is impacting the
of global change have altered the
source/sink function of the aquatic
2
"Changes in the capacity of aquatic
system.
aquatic system sufficiently to alter its
source/sink function for CO of aquatic
systems in the region are sufficient to
2
systems, ocean as well as freshwater, to
source/sink function for CO .
systems in the region by at least 10%.
cause measurable change in global CO
2
2
generate or absorb atmospheric CO as a
balance.
2
direct or indirect consequence of global
change over the last 2-3 decades."
THE GIWA METHODOLOGY
xv