Changes

[[Image:Sand dam.JPG|thumb|right|200px|Sand dam construction in Kitui, Kenya. Photo: M. Hoogmoed.]]

Regions with highly erratic rainfall often have rivers with temporary seasonal sandy bed streams. They only experience heavy water run-off for short periods of time after rain. During such periods of high flows, large quantities of sand are transported downstream. Some sand can get trapped on the upstream sides of rock outcroppings along the stream. The sand traps form natural water storing aquifers. Sand dam technology provides a means to reproduce this water collecting mechanism and to increase the size of existing aquifers.