Conjunctive Use of Detention Dams and Off-Stream Reservoirs, A Tool for High Frequency Floods Management

In this paper the results of investigation on the combination and conjunctive use of Detention dams and Storage reservoirs are presented. Detention dams are basically In-Stream structures while Storage reservoirs canbe built beside streams. Experiments have shown that in areas where water scarcity is a major problem، ground water should not be considered as the only source for water supply. High frequency floods are not commonly recognized as a reliable water supply. This paper intends to reveal the fact that using such an unfamiliar source of water is essential and vital to resolve water scarcity problem in arid and semi arid regions. Combining flood control and water harvesting tasks، may justify Hydro projects from economic point of view. In the case study، it was illustrated that detention dams could effectively capture high frequency floods which leads to local flood control cost reduction. This provides the required investment for constructing off-Stream reservoirs to supply fresh water for different purposes especially for municipal consumption.