Evaulting Positive and Negative Impact of Sand Dam Constrcted in Cadadley

Abstract

In dry land areas like Somaliland shortage of water is very common. People have to travel for long distances to find water, and after it rains, most of the water is lost to evaporation or surface run off. The challenge in arid and semi-arid climates is how to harvest rainwater; most of villages in Somaliland need how to harvest rainwater and running water through their dry valleys. This study aimed to evaluate the positive and negative impact of existing water infrastructure (sand dams) in dry rivers in Cadadley district and to compare these with appraisal of sites yet to be developed that can be constructed sand dams in Cadadley region Somaliland. This study employs a method known as probing, which involves hammering a rod into the middle of the riverbed until it makes contact with the floor beneath the sand, producing a dull sound. The level of the sand is then marked on the rod, which is subsequently pulled straight up without any twisting. The crucial factor in determining the location for constructing a sand storage dam is the depth of the basement or impermeable layer relative to the riverbed surface. Ideally, the dam should be built where the impermeable layer is closest to the riverbed surface. The result shows that sand dam need reconstruction because of short of their spill ways and there is poor choice location.