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Egyptian Environmental Affairs Agency (EEAA)
National Water Research Centre (NWRC)
The Lake Manzala Engineered Wetland Project (LMEWP) in the Nile Delta of Egypt builds on a project concept developed by the Egyptian Environmental Affairs Agency (EEAA) in the early 1990’s to respond to high levels of polluted water flowing from the Bahr El Baqar Drain into Lake Manzala. A combination of land reclamation, population increase and development pressure had resulted in a reduction in the lake surface area, endangered local fish stocks, and water scarcity and ecosystem health risks, which resulted in severe social and economic impacts on local communities that rely on the lake. The initial project idea to construct a large-scale wetland facility capable of treating as much as 50% polluted waste water in the area was modified by EEAA and the Global Environmental Facility (GEF) and support for pilot project planning was secured. This led to the preparation of a project document for the LMEWP for United Nation Development (UNDP) Program by the Tennessee Valley Authority (TVA) in March, 1997. They designed the facility, and supported the local engineering team for the first 5 years after the launch in 1999 with funding from GEF and the Egyptian government. With GEF as funder, the UNDP as implementing agency and EEAA as the executing agency, the project finally concluded in June 2007 demonstrating a low-cost and efficient method of treating waste water in Egypt and promoting a cleaner Mediterranean Sea.
The Egyptian Government, together with the Governorate of Port Said selected the site for the facility, and in January 2001 construction began on a 100-hectare engineered wetland with capacity to treat 25,000 cubic meters per day of polluted waste water from the Bahr El Baqar Drain. Unlike conventional waste water treatment plants, the project constructed a reciprocating gravel system (RGS) based on TVA proprietary design and two sediment basins. Earth ponds were constructed for a 60 acre fish farm, to prioritise the reuse of treated effluent for small scale agriculture and aquaculture research, including fish stocking for Lake Manzala. Two screw pumps are used to lift waste water from Bahr El Baqar into two sedimentation ponds where it is allowed to settle for 48 hours. Water from the sedimentation ponds then flows by gravity through a distribution channel into cells planted with different types of reeds (e.g. Bulrush, Cattail, Papyrus) and floating weeds (e.g. Water Hyacinth, Duck Weed), which further remove pollutants. Following TVA withdrawal in 2003, the services of NIRAS International Consulting were secured to provide technical support. The project reached completion in August, 2007 after the implementation period was extended for two years without requiring additional GEF financial support. It was the first project of its kind in Egypt to combine intake screw pumps, sediment basins, surface treatment cells, subsurface reciprocating cells, pilot test cells, a fish rearing facility, and an effluent reuse area for commercial aquaculture. The Egyptian National Water Research Centre (NWRC) oversees the functioning of the facility and continuous research efforts.
The LMEWP provides clean water to neighbouring communities, with the majority used for irrigation and agriculture and the rest diverted into basins designed for fish farming. The clean water has reduced the risk of diseases from contaminated water and fish, and an enhanced ecosystem has further improved the quality of life of the local population. It provides communities with 50% improved fish growth rates. The project also provides local livelihood support through plant harvesting, seedling propagation, production of fuel and animal feed pellets from harvested biomass; and harvesting of aquatic plants from the wetlands.
The engineered wetland facility (about 100 hectares) treats 25,000 to 50,000 cubic metres of waste water from agriculture, industry, runoff and households per day. Water and sediment quality have improved in Lake Manzala and the Mediterranean Sea due to the reduced inflow of contaminants. The reduction in pollution has improved fish habitats, resulting in greater numbers of healthier and less contaminated fish for other animals that rely on them. More fish and the proliferation of indigenous plant species in the constructed wetland have attracted greater bird diversity.
The Global Environment Facility funding was central to the successful implementation of the LMEWP. The commitment of the Egyptian Government and collaboration with experienced international partners was also important (e.g. the involvement of UNDP and the Tennessee Valley Authority (TVA) responsible for the conceptual design, and later the Danish team from NIRAS assisting with facility planning and monitoring contributed to the success of the project).
The LMEWP effectively treats waste water a with pollutant removal efficiency of 99.7% (Total Coliform), 80% (Total Suspended Solids), 61.2% (Biological Oxygen Demand) and 51.4% (Total Nitrogen). The treated water is utilized for production of crops such as vegetables (tomato, eggplant), sugar beets and Dineiba. The productivity per acre of tomato, eggplant, and pepper crops reached 20, 22, and 12 tons, respectively. During the construction phase, training on engineered wetlands and fish farming was provided to 25 local people.
With the commissioning of the wetland in 2007, the Egyptian government finalised its future management placing it under the National Water Research Centre (NWRC) and its Drainage Research Institute (DRI). The NWRC has committed financing to operate and oversee the functioning of the facility, and to continue research efforts. The NWRC is considering the extension of the Bahr El Baqar Drain technology for treatment of domestic sewage for villages on the fringes of the Delta Region. To guide its operation and potential expansion, NWRC received a series of reports from LMEWP consultants giving detailed recommendations on facility operations and maintenance, monitoring, business planning and further research efforts.
Unresolved land ownership issues in the Delta Region remain a key constraint on upscaling efforts. Also, multiple agencies at the national and governorate level have overlapping authority over water pollution, agriculture drainage and fisheries, making accountability a challenge. An overly technical focus on the wetland’s construction and operation has come at the expense of meaningful engagement with wider communities, limiting their buy-in and support. Considerable pollutants still drain into Lake Manzala, threatening fish cultivation and other activities. The reciprocating treatment system technique is yet to function as planned because of the unexpected withdrawal of TVA involvement due to security concerns in 2003.
