Sand Dams

When it rains the dam captures soil laden water behind it which eventually fills the dam. However the sand holds a lot of water which can be drawn out by a tap at the base of the dam, providing a source of clean water for a long time after the annual rains. The water trapped in the sand also percolates into the surrounding are which can be planted with crops. This is a simple way to improve health and food supply and is very cost effective as only the basic materials are needed and the local residents provide the work to build the dam.