Underground dam site selection using hydrological modelling and analytic network process

The location of Iran on the dry belt of the earth has caused the expansion of the desert in central and southern regions. One of the supply water methods in these regions is the underground water resources. Underground dam is one of hydraulic structures to storage and recharge water into the aquifer. The aim of this paper is to determine the best location to build underground dam using hydrologic and network process models. In determining the location of an underground dam, many factors can be considered. One of the most important ones is the subsurface flow in the area. In this study, hydrological modelling was done by SWAT to calculate the subsurface flow. At first, by using the Boolean logic method, seventeen suitable locations were selected. The selection process was based on criteria such as ground slope, land use, geology and hydrology. Then, the areas were modelled in SWAT and the subsurface flows and runoff volumes were calculated by SUFI2 (Sequential Uncertainty Fitting Ver. 2) algorithm. In the next stage, the locations were ranked using the Analytic Network Process (ANP). The decision criteria that were considered in ANP included reservoir volume, dam axis, and economic and social issues (drinkable water demand, Agriculture water demand, Distance from road Distance from village). Finally, 17 points were selected and prioritized for underground dam construction. The results of this study point that combination of SWAT modelling and ANP can be considered as a useful approach in the selection and ranking process in identifying optimum sites for underground dams. The results of this study made it possible to identify suitable places for the construction of underground dams by saving time and money by using the