Groundwater spring potential zonation using AHP and fuzzy-AHP in Eastern Himalayan region: Papum Pare district, Arunachal Pradesh, India

In the present study, the groundwater spring potential zone (GSPZ) was identified using an integrated approach of remote sensing (RS) and geographic information system (GIS), analytic hierarchy process (AHP), and fuzzy-AHP based on multicriteria decision-making (MCDM). Thus, ten associated factors with groundwater springs have been considered: slope, drainage density, lineament density, geomorphology, lithology, soil texture, land use and land cover, rainfall, groundwater level, and spring discharge. The analysis output was categorized into low, moderate, and high. The result of the AHP model shows the area under the high potential zone (16.61%), the moderate potential zone (60.42%), and the low potential zone (22.61%). The result of the fuzzy-AHP model shows that the area falls under the high potential zone (30.40%), moderate potential zone (41.29%), and low potential zone (22.61%). The validation results showed fuzzy-AHP with the area under the curve 0.806, which is slightly better than 0.779 of AHP. So, the resulting GSPZ map confirms that the thematic layers used in the study have a significant role in groundwater spring occurrence and distribution. It was recommended that any groundwater spring rejuvenation or protection activities must be implemented in medium to very high potential zones.