Eawag: Water Resource Quality: Filter Technologies and Implementation

Due to a lack of alternative water resources in the Rift Valley, treating fluoride-contaminated groundwater is currently the only viable option for reducing the risk of fluorosis. Treatment technologies need to be cost-effective and affordable for the local population and ideally involve locally available materials.

Fluoride removal filters based on animal bone char combined with calcium phosphate pellets (contact precipitation) have been develpoed and implemented in Kenya by the Water Quality section of the Catholic Diocese of Nakuru (CDN). These types of filters are now being tested in the Ethiopian Rift Valley. CDN has supplied initial filter material and is supporting the local NGO OSHO (Oromo Self-Help Organisation) to set up a bone char kiln in Ethiopia in a project funded by Swiss Interchurch Aid (HEKS).

The project kick-off meeting in Ethiopia in May 2009 was used to identify key stakeholders, to set criteria for field-site selection, tariffs and an exit strategy for the project. In collaboration with local woreda (county), kebele (village) and our field partner OSHO, a contact precipitation community filter was constructed in Weyo Gabriel (Oromia region, between Meki and Ziway) and opened on 9th May 2010.

		The water price of this filter was set at 0.50 Ethiopian Birr (around 3 US cents) per jerry can (20 L). With this income, the responsible water committee is able to pay around 50% of the filter material replacement costs, the salary of the caretaker and the costs for pumping of raw water.