Comparison the AHP and FUZZY-AHP Decision Making Methods in Underground DAM Site Selection in Taleghan Basin

In recent decades digging deep wells and a half deep flume was gradually replaced aqueduct that by the relative merits is attended the great environmental effects such as loss underground water level and creating subsidence phenomenon for most regions of interest. Recent studies have been accomplish in order to replace the underground dams instead of medium and small dams in order to optimize storage and use of water resources and reduce the environmental impacts. Site selection of underground dams quite complicated process due to geological, geomorphological and hydrological point of view. Determination of the role adjustment and importance of the variables is based on expert groups thoughts and usually this important is verbalize in linguistic variables form. Analytical Hierarchy process have possible in using the linguistic variables along quantitative variables and essentially is based on expert opinions. In recent years in order to increase the capability of AHP, this method combined with fuzzy method and in the Fuzzy-AHP algorithm is presented. In this paper two methods of AHP and Fuzzy-AHP were used in determining appropriate areas for underground dams. Buckley and Bonissone methodes was used for implementing Fuzzy-AHP method and Yager method was used for defuzzicating fuzzy utility values. From totale 56 outputs points of subbasine in AHP method, 26 points and in Fuzzy-AHP method, 15 points were overlapping with suitable and accessible areas. The results showed that the Fuzzy- AHP method has more flexibility and greater ability to determine appropriate areas dam.