The sediment budgets of hill reservoirs in small catchments in North Africa and the Middle East

Global assessments place the loss of reservoir storage by sedimentation at 1% per year. The cost of recovering such storage may be prohibitive. In Mediterranean countries, the situation is worse due to widespread land degradation. Trapping the sediment that comes primarily from the upstream mountain zones in small and relatively inexpensive reservoirs is important. The construction of small dams at different points on the stream network also attenuates flood flows and reduces the erosion potential of storm events, which are often of high magnitude in the Mediterranean region. Within this framework, 32 artificial reservoirs situated in the Tunisian Atlas Mountains, the Rif Mountains of Morocco and the Homs basaltic plateau of Syria, were chosen to constitute a network for hydrological observations. This paper synthesizes the results obtained from this hydrological network. Guidelines relating to the effective assessment and management of the sediment budgets of small hill reservoirs in the Mediterranean region are provided.