Groundwater Dams, A reliable approach for reducing drought effects in arid and semiarid regions

Many developing countries are located in areas where the rainfall is seasonal and unpredictable. Necessary water prepare by saving water in wet seasons and years for applying in the dry seasons or years in these countries. One of the suitable methods to manage drought effects is applying of groundwater. But these water resources ending in the end of dry season in some arid regions. The use of groundwater dams is one of the water storage methods that have been considered in recent years. Compared to conventional storage dams,groundwater dams have many advantages. In this method, evaporation losses reduced or even completely disappear. Groundwater dams, once and for always being developed and the water storage is available for a long time while the volume of reservoir in surface dam reduced due to deposition of sediments and plant growth and also regularly subjected to evaporation or damage due to severe floods. In this way, the stored water is less polluted and health hazards such as malaria and snail fever outbreak there in surface reservoirs is excluded. Subsurface dams and sand storage dams are two groundwater dams which are being implemented. Subsurface dams are constructed below ground level and will block flow in the aquifer. But the sand storage dams, store water in the accumulated sediments behind the dam. This article is merely to examine various aspects of findingsites and buildings methods of sub-surface dams as a very useful tool for arid and semi-arid areas