Predictive Study of Silting and Durability of Tessa Planned Dam -Tunisia
Abstract:
The mobilization and exploitation of surface water are ancient practices in Tunisia. Solid inputs from upstream watershed threats the life of Dams that cause its siltation. Predicting the rate of erosion upstream the dam is very important in order to monitor and manage the siltation problem and to designate adequate means to reduce its extent. The main objective of this paper is to estimate the siltation rate of Tessa planned dam by RUSLE model (Revised Universal Soil Loss Equa-tion). To apply the model, the use of mapped field information requires the use of a Geographic Information System to properly plan the man-agement actions to be taken and to protect priority areas at erosion risk. The simulation of the thematic maps of the RUSLE factors, will allow a very efficient way to unravel the complexity and the interdependence of the factors, such as slope, soil erodibility, rain erosivity, land cover, and existing landscaping; to predict the volume of the vase the current rate of sediment according to the model is therefore (53 t/ha/year); the sediment rate in the dam is expected to be in the order of 950 Mm3. After integration and combination of scenarios, this rate will decrease by 10%.
