Prioritization of potential areas for construction of underground dam using geometric average method in geographical information system

Exploitation of underground water resources is a way to modulate the shortage of seasonal water. In this regard, proper site selection for constructing underground dam to reserve waters is a challenging issue. Thus, using an approach with minimum error is essential. The purpose of this paper was optimum selection of potential sites for constructing underground dam in Hamedan-Bahar catchment basin using a new GIS-based approach to reduce the error. For this, the efficient criteria of a proper site to make underground dam were first recognized. These criteria include density of drainages, separation of the aqueducts, spring and wells, geological appropriate, slope, fault density, proximity to roads and villages and special conditions of land use. Then, different evidence layers were weighted in [0, 1] range using logistic function in geographic information system. Finally, the weighted evidence layers were integrated using geometric average function. Thus, a model representing favorable areas for making underground dam was generated. The results obtained introduced less than 10% of the streams (respecting the whole streams in the study area) as suitable, and demonstrated that the method applied can be used efficiently to delimit the study area and to recognize suitable streams for construction of underground dam.