Reducing Pollution – Constructed Wetlands
Introduction:The Session was initiated based on a need to see more constructed wetlands being constructed in order to target the growing need for low cost low-tech wastewater treatment systems. The session consisted of three presentations displaying case stories from different regions and on different scales. The primary focus of the implemented systems was domestic wastewater.
Program:
The Session was introduced after which followed interesting and knowledge packed presentations on a range of low-tech wastewater treatment solutions, primarily focusing on constructed wetlands.
Ningbo Water and Environment Project – South China
– SPEAKER: Nicholas Kotschoubey
Lake Manzala Engineered Wetlands – Egypt
– SPEAKER: Mohamed Bayoumi
WIO LABs Experiences on Constructed Wetlands – South Africa, Kenya
– SPEAKER: Peter Scheren
The relative low number of presentations enabled room for some discussion. As the outcome of the session suggests there was a lot of interest and energy to understand and implement such technologies. (Please see appendix for more detailed insight in the questions and answers.)
The presentations catalyzed a good dynamic atmosphere where knowledge and experiences were exchanged in the group. [1] The Session was attended by approx 25 people out of which all were active participants in the discussion.
Innovations:
The technique behind the Constructed wetlands is a well-known and scientifically proven technology. Hence, the session did not showcase any new innovations as such, but a range of applications on different scales were presented. However, the presentations did bring forward following innovative designs/features:
Way forward:
The plenum along with presenters expressed the need for material that would enable them to promote constructed wetlands nationally as well as locally, including costs of constructing wetlands, social participation, technical applicability, economical benefits, etc).
The Plenum expressed the need for establishing a group within the IW portfolio to share experiences with and to use for reflections and continuous developing their knowledge base. Hence it was decided that a group will be established under GEF IWLEARN. The group will consist of following individuals in the initial phase:
Dr. Yang Yang, Director for Research Center for Environmental Analysis and Aquatic Ecosystem South China Insittute of Environmental Sciences, NEPA. China
huahyang@scies.com.cn, huanyang@public.guangzhou.gd.cn
Dr. Roberto Castellanos Perez, Delegate for the Ministry of Technology and Environment, Cuba
Stephen Adrian Ross, Senior Programme Officer, Regional Programme on Partnerships in Environmental Management for the Seas of East Asia (PEMSEA), GEF/UNDP/IMO, Philippines
Charles Gyasi, Business Development Associate, Worrell Water Technogies, USA
Jonathan A Allotey, Executive Director, Environmental Protection Agency, Ghana
Prof. J.P.Msangi, Dean, Faculty of Agriculture and Natural Resources, University of Namibia, Namibia
jpsaangu@unam.na, jpmsangu@iway.na
Prof. Chidi Ibe, Executive Secretary/ Regional Director Guinea Current Large marine Ecosystem Project, Ghana
Dr. Tessa Goverse, Task Manager, Assessment and Science Projects, Division of GEF Coordination, UNEP, Nairobi
Isao Endo, Environmental Economics Officer, UNDP/GEF Project on Reducing Environmental Stress in The Yellow Sea Large Marine Ecosystem, Korea
Mirey Atallah Portfolio Manager, International Waters & Land Degradation, UNDP, Lebanon
Dr. Peter Scheren, Project Manager, UNEP/GEF WIO Lab Project Management Unit, Nairobi
Prof. Sameh M. Afifi, IWRM Project, UNDP, Egypt
Christian Severin, Programme Manager GEFSEC, USA
Appendix 1
Hi Christian,This is just from the question and answer sessions. I have a few notes from the presentations, but I assume that they gave you their PowerPoint presentations? Let me know if you need those as well.
KarinConstructing Wetlands: Reducing Pollution
Ningbo Water and Environment Projects: Question and Answer Session
Question: CS
How did you come up with that idea?
Answer:
(i) constructed wetland
(ii) natural restored wetland
(iii) education centre
(i)-(iii) all on the same site.
Waste water treatment and further nutrient removal
Five kinds of wetlands; actually on an estuary (an important fishery)
[did not answer the question: perhaps due to language barrier]
Question:
Is there any harvesting / commercial value form the wetland?
Answer:
No commercial value.
Communities used to harvest mollusks. But as it is the only tidal natural wetland left, its conservation is of higher importance, especially as a breeding ground.
The visitors centre charges a fee
Farms have been asked to stay out of the area
Question:
Was there any negative impact because of Avian Flu in waterfowl and wetlands?
Answer:
Local government and developers want to attract birds
Question:
Is all the vegetation natural? Did you introduce any non-native species to help with absorption of nutrients/contaminants/metals?
Answer:
All species are natural
Question:
Any plans to expand the project to other areas? Is this one time only / a pilot project?
Answer:
Yes, it is a pilot project. China wants the project to be copied to other cities and provinces if it is successful
This is a demonstration project. World Bank wants to identify other areas where the same technology can be applied.
Question:
Is there monitoring of the effectiveness of the different types of wetlands? Constructed vs. rehabilitated wetland effectiveness?
Answer:
Indicators:(i) number of visitors / workshops
(ii) BOD, Nitates, Phosphate levels
(iii) Abundance of benthic fauna / birds
No comparison between different types, there is only one wetland system
Lake Manzala
Question:
Worried about the depths of the sedimentation cells? How did you achieve effectiveness in achieving suspended solids dissolving with shallow depth?
Answer:
Design called for big/wide sedimentation ponds
Question:
How do you get rid of the pollutants?
Answer:
Vacant land where they store waste
Use it for compost
Machine to make bricks from sediment (concept)
GEF should look into the effect of the pollutants i.e. once the water has been cleaned
Clay soil has low porosity and soil movement, therefore waste is not a danger to underground water
Question:
What are the costs associated with this system?
Answer:
Very cheap, but needs a large land area. Do not have a cost analysis, due to the use of many external consultants – we are trying to bring this cost information together.
System is maintenance free; environmentally friendly.
Limitation: land is expensive to acquire
Working with IW:LEARN regarding costs: check the website.
UNEP/GEF WIO-Lab Project
Comment:
Need marketing mechanisms to sell these ideas to NGO’s and governments.
Question:
Land is a limitation; type of waste water is a limitation (industrial vs. domestic) – different challenges
Answer:
Industrial waste: heavy metal accumulation in plants; cannot feed to livestock
Comment:
In Ghana, marketing of the products e.g. fish is an issue
Question:
Local perception of these systems?
Answer:
The land was taken from encroachers on the government owned land.
Question:
Suspicion about the final product i.e. fish?
Answer:
The fish is safe for human consumption, but it is a marketing issue: need to change perceptions and make people aware.
Important to include local community in the project and find a role for them that allows them to generate income i.e. fertilizer sales
Ghana e.g. gave the land back to the people to manage the project once it was running.
Question:
How did Ningbo get the mayor involved without convincing/positive results to get his cooperation?
Answer:
The project has clear benefits for the environment
Economic and social benefits
36km bridge over the project area: project has a high visibility (promote project); gives a good impression; shows that the Mayor has an interest in the environment
[1] The session facilitator highly benefited from the excellent “rapporter” that was present. Thank you Karin.