SILTATION OF THREE SMALL RESERVOIRS IN JORDAN

Siltation of three small dams in the north western part of Jordan was investigated. Two of the dams (Sharhabiel Bin Hasnah and Alghadeer Alabyadh Dams) were constructed 39 years ago (1966). The designed total reservoir storage capacities of these dams were 4.4 and 0.7 million cubic meters respectively. The third, Sad Wadi Alarab dam, was constructed in 1986 with a total storage capacity of 20 MCM. The actual storage capacities of the three reservoirs were calculated using echo-sounding traverses. The data obtained were used in special computer software to construct the bathymetric maps of each reservoir and consequently calculate the existing storage volume. This technique was used for each reservoir and the results showed that the reservoir storage capacities were reduced at an average annual rate of 0.046, 0.017206 and 0.446857 MCM respectively. Bottom sediments of the reservoirs were collected using van-veen grab and analyzed. In all the cases, sand, silt and clay were the main sediment components.