Delineation of groundwater potential zones using GIS and multi influence factor (MIF) techniques: a study of district Swat, Khyber Pakhtunkhwa, Pakistan

The efficient groundwater utilization, planning and management, is inconceivable without the proper recognition of potential zones. The present study aimed to assess the groundwater potentiality in district Swat, Khyber Pakhtunkhwa Province, Pakistan. The weighted overlay analysis methodology is used in this paper. A total of seven influence factors were used in the present study, viz. slope, drainage density, geology, rainfall, soil, land use/land cover and lineament density. The weight and score of each influencing factor is computed using multi influence factor (MIF) techniques. Within each influencing factor the subclasses were assigned a weightage of (A) (major effect) and (B) (minor effect) depending upon their effectiveness to the recharge of aquifers and groundwater potentiality. The combined weightage of both major and minor effects (A + B) was considered for computing the relative effect which was used to compute the score of each subclass within each influencing factor. The thematic layers were then integrated with weighted overlay using ArcGIS 10.2.1 and groundwater potential zone were delineated. The delineated groundwater potential zones were classified into four categories, i.e., (1) poor, (2) good, (3) high and (4) very high potentiality. The findings revealed that very high groundwater potential zone cover an area of 342.57 km(2) (6.7%), high 1506 km(2) (29%), good 2384.8 km(2) (45.91%) and poor 960.28 km(2) (18.48% of total area). The results of this paper are believed to be useful for effective groundwater harvesting and management and can also be used as helping material for future research work.