A view to rainwater utilization and its role in rural areas development in arid and semi-arid regions of Iran

One of the most important problem in arid and semi-arid regions is shortage of water. Low flow Springs and seasonal rivers, that usually flows in winter and spring time, are the most water sources in such areas, Seasonal floods that flow after heavy seasonal or cyclic precipitation are the most important indication for such rivers. Therefore, Make use of rainwater utilization system in these areas is necessary, because of they essential role on agricultural, civilization and social-economical development. One of the most common system for storing rainwater and low flow springs is cement and earth ponds in various sizes and shape that usually are constructing by local people. Filling these systems usually have done by two simple and economical methods as follow: 1- make use of slope runoff and seasonal rivers flow in gravitational method. 2- make use of subsurface flows that appear in low flow seasonal springs. In this paper introduce common rainwater harvesting system and then individually would be refer to rehabilitation role of these systems (above mentioned) and their problems and other characteristics in typical region in north west of Tehran (south of Alborz mountain) as follows: a) investigation of distribution, shape, size and technical problems of these systems in mentioned region. b) explain of watershed management activities and innovation systems have done by people for make use of harvested water by means of agricultural development. c) assessment of problems related to sedimentation. d) Investigation of slope instability risk under influence of loading by criterionless development of these structures on slope. e) Discussion, conclusion and suggestion for optimization of systems.