GIS based Spatial Groundwater Recharge estimation in the Jafr basin, Jordan – Application of WetSpass models for arid regions

Abstract

The spatial variation of groundwater recharge depends on distributed land-use, soil type or texture, slope, groundwater level, and meteorological conditions. This study was initiated to estimate groundwater recharge using the WetSpass spatially distributed water balance model. The groundwater recharge in Jafr basin takes place primarily in the outcrop area of the western highlands by direct and indirect infiltration of rainfall. Due to sparseness of vegetation and steep topography, most of the recharge occurs by infiltration of runoff accumulating in the wadi beds during rainstorms. The long-term temporal and spatial average annual rainfall of 53.5 mm was distributed as 2.61 mm (4.9%) of surface runoff, 50.6 mm (94.6%) of evapotranspiration, and 0.27 mm (0.5%) of recharge. This recharge corresponds to 3.67 Mm3 for the Jafr basin. Analysis of the simulated results reveals that WetSpass works well to simulate the components of the hydrological balance for the Jafr basin.