Addressing water scarcity requires innovative approaches, technological advancements, and sustainable water management practices. The main objective of the current study is to estimate the quantity of stored surface water to be used with the existing groundwater, which its locations and distributions were determined from the gathered field measurements and data, for reclaiming the new agricultural lands in Wadi Dihmit region. This study used Geographic Information System (GIS), Watershed Modeling System (WMS), and Remote Sensing (RS) to determine areas that are affected by flash floods and delineate the watersheds of Wadi Dihmit. GIS was used to assemble information from different maps, satellite images, and Digital Elevation Models (DEMs) to select the best location for constructing an obstruction dam. Wadi Dihmit is located in the Eastern Desert of Egypt and the eastern south region of Aswan. Wadi Dihmit is the largest Wadi in the Eastern Desert of Egypt after Wadi Al Allaqi. It starts at a distance about 25 kilometers southeast of the High Dam. The total area of Wadi Dihmit is 4925〖 km〗^2; more than 34% of this region is sandy and valley deposits, so the chance to reclaim this region is high. It is necessary to use modern irrigation methods in the reclamation lands of Wadi Dihmit. Based on the existing irrigated areas, which are surrounding Nasser Lake, it is possible to cultivate some kinds of plants, that can adapt to the high rates of temperature, evaporation, and salinity such as olives, dates, grapes, beat, corn, wheat, and medical plants.