POTENTIAL SITE SELECTION FOR GROUNDWATER RECHARGE USING ADVANCED GEOSPATIAL TECHNIQUES

Abstract

Freshwater demand is increasing rapidly due to a significant increment in population day by day. Whereas, groundwater resources are depleting at high speed in fulfilling the water needs of different sectors. The world uses 67% of groundwater for agriculture, 22% for domestic and 11 % for the industrial sector Twenty-five percent (25%) of global groundwater withdrawals sustains agricultural productivity in Pakistan, India, Nepal and Bangladesh. Pakistan is the fourth largest user of groundwater among all countries (after India, the USA and China) Punjab is the largest populace province of Pakistan where around 90% of the population is dependent on groundwater to fulfil their domestic, agricultural industrial needs. It has been reported that in many parts of the country ratio of groundwater recharge to discharge is 0.8 which also results in a rapid decline in the water tables country. This study aimed at the assessment of the potential sites for groundwater recharge in Jand tehsil using a geospatial approach. Presently, the study area experiencing the seepage/mixing of wastewater with the groundwater due to poor drainage and sewerage network. Therefore, availability of fresh drinking water becomes a serious challenge in Jand and demands an artificial groundwater recharge system to fulfill the water needs. Several relevant criteria have been incorporated in this research to delineate the potential zones i.e. Drainage Density, Slope, Rainfall, land use/Landcover, Geology, and Soil. To precisely identify the sites, an Analytical Hierarchy Process has been employed to calculate the weight of each criterion. Subsequently, each factor is multiplied by its respective weights to develop the potential site suitability map. Results of the study revealed the three best groundwater recharge sites and classified the suitability of the study region as; high suitable (34%) moderate suitable (35%) and low suitable area around 31%. This research illustrates the strength of Geospatial techniques in proposing the potential ground recharge regions and hence rainwater and groundwater resources can be managed efficiently.