Using Integration GIS and Remote Sensing Techniques by Decision Support System to Locate Suitable Areas construction of Underground Dam (The Case Study of Qazvin province)

There are numerous criteria which should be assessed in order to locate potential underground dam sites، and that’s what makes the location process difficult. Therefore، in this study، in order to create a link between these criteria and thus to make an accurate decision and to save time and money، we use a method which combines GIS (Geographic Information System) and RS (Remote Sensing) with SDSS (Spatial Decision Support System). This method was implemented in three steps. In the first step، unsuitable areas for underground dam construction were omitted through applying GIS and RS with regard to exclusionary criteria، and ultimately 9 sites were identified suitable for the construction. In the second step، the best gorge of each selected area in the first step was chosen by using a terrain map and was considered as dam axis. In the third step، we used the criteria derived from expert opinion to compare and evaluate the axes against the criteria through AHP method (Analytical Hierarchy Process) and to rank the axes by each axis’s final fit index. Eventually through field visits and complementary experiments such as geophysical studies، mapping، permeability tests and etc. the model accuracy was studied in three first priorities including the axes number 2، 4 and 1. These studies showed that the results of the model presented in this study، are consistent with the results of complementary studies، and the accuracy of the model was confirmed.