A Comparative Study on Precipitation and Groundwater Level Interaction in the Highly Urbanized Area and Its Periphery

Abstract

Precipitation is the primary source of freshwater. The availability of water in an area is largely dependent on precipitation that is further distributed into various components such as aquifer recharge, evapotranspiration and surface runoff etc. Aquifer recharge is one of the significant sources of groundwater that is affected because of increasing the urban sealed areas. Urbanization brings numerous artificial changes by altering natural earth surfaces into impervious areas that result in reducing infiltration. The changes in the urban land covers modify the natural drainage system and affect the groundwater recharge systems. As precipitation is the major source of groundwater, it is important to evaluate its influence on the aquifer recharge. Thus, this study is conducted to explore the interaction between precipitation and groundwater level. A comparative analysis is performed between urban and suburban environments. The results show that both urban and suburban areas experience groundwater depletion but the rate of depletion is high in urban areas compared to its suburban. The results also demonstrate that during monsoon, the groundwater level changes in the urban periphery but the water level remains static in the urban areas. The urban areas include more sealed areas that prohibit direct recharge, therefore, in urban areas, no significant relationship is observed between precipitation and groundwater level. In contrary, the influence of precipitation on groundwater level is observed in the suburban area therefore, relatively a high correlation is observed.