Determination of artificial recharge location using analytic hierarchy process and Dempster–Shafer theory

Abstract

Groundwater is an essential and major source of water in semi-arid and arid regions, and thus, determining potential locations for groundwater recharge, via prompt and accurate techniques, is necessary. The aim of the research is finding the best artificial recharge location for injecting the excess surface water into aquifer in Shiraz watershed comparing fuzzy-AHP method and Dempster–Shafer theory (DST). The former employs membership functions to determine the importance of each factor in artificial recharge and generates fuzzy maps through analytic hierarchy process (AHP), whereas the later takes the level of confidence, management strategy and geographic conditions into account. The outcomes of this study demonstrate the applicability of the proposed methods for the artificial recharge location prediction. The DST is among the foremost tools, which produces an artificial recharge map at a given level of confidence. For Shiraz watershed, three levels of confident of 99.5%, 99%, and 95% were applied and the results were compared with fuzzy-AHP method. The fuzzy-AHP method identified ~ 19.76% and 6.02% of the study area as highly suitable and unsuitable classes, respectively. While in the DST, the method identified ~ 32% of the area as moderately suitable. The comparison of the two methods to determine the best location for artificial recharge showed that the fuzzy-AHP method had a lower accuracy than DST in determining suitable locations for artificial recharge. Additionally, the DST method can generate several maps with different confidence levels that suit the economic conditions and importance of the study area.