ECVM, in partnership with Dutch NGO Agua4All, has donated PVC pipes and technical expertise for a new waste water system on Pemba Island in Zanzibar.
The project, which uses international aid to enable local communities to help themselves, is designed to improve the quality of life for local residents, minimise the environmental impact of waste water on the marine ecology and sustain the local economy.
Waste water challenges in Pemba
Pemba Island, part of the Zanzibar Islands, is situated in the western Indian Ocean. A combination of the natural terrain, lack of awareness around pollution and financial restraints, has resulted in raw sewage being discharged into the marine environment.
This untreated waste affects the ecological balance and sustainability of coastal systems that support the livelihood of the coastal population. Fishermen in Chake Chake, the main commercial area of Pemba, have seen a significant decline in fish catches over recent years. Waste water discharge into the sea is seen as a key cause of this trend.
The elongated natural drainage channels in the Msingini, Mtoni and Kichungwani wards of Chake Town, which serve 650 households and carry away storm and waste waters, are interrupted by unplanned settlements. This has a big impact on the efficiency of the waste water system. Additionally, many septic tanks and soak pits are old and leaking, causing pollution and health risks for the local communities.
A new system
To tackle these problems, a brand new sewage system with a sub-surface flow constructed wetland, was built to serve Msingini, Mtoni and Kichungwani.
A new network of pipes was laid, coupled with the construction of an anaerobic pond and sub-surface flow constructed wetland for biological treatment of the waste collected in the pond. The treated waste is then brought into the ocean via existing open channels.
ECVM donated 80,000 euros worth of PVC piping totalling a length of 12.1 km, as well as 590 inspection chambers. Additionally, ECVM experts’ assisted local teams with the project design to help, advise and develop the details of the technical assistance required for implementation.
The benefit of donations in kind, such as the PVC pipes supplied by ECVM, compared to direct funding is that they generate the structural and logistical conditions from which local communities can benefit. This includes creating employment.
The value of PVC
PVC sewage pipes have numerous benefits; they are tough, light-weight, stiff, have a high tensility and hoop strength, and good creep characteristics. This unique combination, coupled with excellent corrosion resistance and the ability to make reliable pipe joints easily, results in a product that compares favourably with competitive materials.
The service performance of PVC sewage pipes is outstanding. They have low failure rates and deterioration is minimal.
Challenges and benefits
The project was not without challenges. Local engineers and workers had to deal with broken, old sewer pipes, which allowed water to enter the trenches, and water entering the main discharge tunnel, which slowed down the embankment construction. A high water table throughout the construction period meant ground water seepage into the ponds, delaying the excavation of the sites, anaerobic ponds and wetland.
Ultimately these challenges were overcome. The new waste water system will reduce marine pollution, empower the local community to take responsibility for their waste management and increase public education and awareness on waste water management issues, leading to the reduction in risks associated with waterborne diseases. It will also improve the local municipality’s environmental management processes.
A partnership approach
ECVM was one of a number of international and local Pemba Island organisations that helped to make the 185,000 euro project a reality.
These included Aqua4All, the Dutch NGO which combines money and expertise from the Dutch water sector for the facilitation of water and sanitation projects in developing countries with commercial organizations, and the United Nations Environmental Protection section of the Global Programme for Action for the Protection of the Marine Environment. WIOLAB, a regional African initiative in reducing pollution activities in the West Indian Ocean and the Tanzania Social Action Fund were also involved.
Key local stakeholders in Pemba included the Municipal Council WIOMSA, the Department of Environment of Pemba, the District and the Institute for Marine Science (IMS) from Dar es Salaam.
Public and private partnerships between international and local organisations are becoming increasingly popular as water utility companies struggle to serve a growing population, particularly in poor regions of the world.
“Our ECVM-Aqua4All partnership focused on developing new services in favor of the local populations by taking on additional risks and filling in gaps in the financial market. Our input helped to overcome the limits the local organizations initially faced to ensure that this project happened”, said Jean-Pierre De Grève, Communication & Advocacy Director, PlasticsEurope. He also added that the project demonstrated that PVC is a sustainable product, ideally suited to use in developing countries, as it remains in place for more than 50 years.
