Assessment of Temporal and Spatial Variations of Excess Water in Some Watersheds the ProvinceofArdabil

Assessment of quantitative variationsof the surface water resources in the temporaland spatial scale in some watersheds the province of Ardabil will provide the possibility of balancing and optimal allocationof water resources in the current and future situations. Water resource managers need to have access to reliable information about the amount of available water and costs to decide on the allocation of this resource. The purpose of this study is to evaluate the temporal and spatial variations of excess volume in surface waters in some watersheds the provinceof Ardabil. The data collected at 23 hydrometry stations during the 1989–2014 periodin 21 watersheds were evaluated. The Water Stress Indicators (WSI and WSIef) were calculated. Excluding the Mashiran, Buran, Dostbeiglou and Samian stations, the remaining stations do not have too much excess water in most of the months and seasons, especially during the warm months. The difference between the results of the WSI and WSIef indexes indicate that in order to meet the needs of different sectors of agriculture, drinking and industry the province of Ardebil, not only the discharge of the rivers are consumed, but also the environmental flow is taken from the rivers. By exploiting the environmental flow,thus not considering it in thewater resources management system, the survival of surface-dependent ecosystems is at stake.