Wadi Al-Fedan is a major corridor for running water and rainwater from surrounding areas on a large scale, for this reason the construction of Wadi Al Fedan Dam has been initiated with the aim of collecting and using water resources mainly for agricultural irrigation and domestic use -Al-Fedan dam is a Rock fill dam with reinforced concrete slabs at upstream side, The reservoir capacity is 3,400,000 m3, a 100m length spillway with a level of 20m from the Wadi bed over the crest of the dam and a concrete stilling basin. The spillway is designed to carry a flood peak of at least 200-year flood which is 767.78 m3/s, in addition to a minimum freeboard above the flood flow surface not less than 1 m. Depth of water above spillway crest at reservoir is 2.73 m and the dam crest should be at 24.50 masl with approximately 1.27 m of free board. The diversion tunnel (L= 160 m, b/h = 3.50/3.00 m, slope 1.8%) is designed to drain flood safely with minimum damage to dam body during construction period. The same structure will accommodate the outlet works and the bottom outlet. Outlet steel pipe of 600 mm diameter is installed through the diversion tunnel to provide the required yield of water for the downstream.