Abstract
Groundwater recharge is a complex phenomenon to understand and describe because it cannot be seen with open eyes. We have to depend on some theoretical assumptions to understand this complicated hidden natural underground water movement process. There are many factors affecting and controlling the water movement in soil profile. Groundwater use in district Chakwal is of a fundamental importance to meet the rapidly expanding drinking and agricultural water requirements. The main factors contributing to groundwater recharge in Chakwal are rainfall, evapotranspiration and geology. Due to the semi-arid climatic conditions of the area, this resource is almost the only key to economic development. There are a number of dug wells in the area where water is getting stored during rainy season. Sources and processes of recharge in humid areas are different compared with semi-arid areas. Due to the main source of available water in the area, the potential groundwater recharge estimation could be good exercise to visualize the amount of rainwater entering the ground. For groundwater recharge estimation there are a number of simple and advanced techniques available. In the present study simple methods were used to estimate potential recharge due to available limited resources. Rainfall runoff, gravimetric and water table fluctuation methods were used to quantify rainfall recharge during the monsoon season. The average potential recharge estimated was 60% of the rainfall of 148 mm. Rainfall runoff and gravimetric methods were found to be comparable for short period potential recharge estimation while water table fluctuation method gives actual recharge and require longer period data. Potential recharge values were higher for area having grassland type vegetation and low for area covering shrubs and thick vegetation.
Keyword(s)
Semi Arid, Plateau, Gravimetric, Rainfall Runoff, Water Table Fluctuation