Levels of water access provided by sand dams were assessed by measuring water presence and use in a repre-sentative sample of 97 dams in Kenya. Most dams were filled with sediment capable of holding water, with a 25% median reduction of water capacity due to siltation when using a high estimate for sediment specific yield. Multiple sediment cores taken from each dam indicated the presence of water in over half of sediment cores from 57% of dams. Although there is individual variation, generally dams in the region were therefore capable of accumulating water. Analysis of Landsat satellite images indicated that this did not translate into an average increase in vegetative greening and moisture indices at dam sites compared to controls sites. Observational data on activities at dams indicated variable levels of water use; only 43% of dams had active water harvesting present, and only 39% of dams had current agricultural activities adjacent to the sand dam site. Cross-sectional comparison of data did not indicate consistently higher levels of water harvesting or agricultural use at dams with more water. Results point towards a high level of community understanding of sand dam benefits, but a lower rate of actually realizing those benefits.
Neufeld, DG; Muli, J; Muendo, B; Kanyari, J
Assessment of water presence and use at sand dams in Kenya
Journal Of Arid Environments