Assessing artificial groundwater recharge on irrigated land using the MODFLOW model

Abstract

Water-resource deficits have led to the need for artificial groundwater-recharge techniques to provide drinking water for rural communities in southeastern Kazakhstan, especially those with a small number of inhabitants. The Kishi-Tobe settlement located in the Karatal agricultural area on the right bank of the Karatal River in southeastern Kazakhstan has severe water-supply shortages. In this study, the groundwater-flow model MODFLOW was used to simulate complex hydrogeological and irrigation conditions for a quantitative assessment of artificial groundwater recharge from infiltration pools. The aim of these pools was to solve the water shortage in the Kishi-Tobe settlement. New findings showed that the maximum rate of artificial groundwater recharge from the infiltration pool can reach 1000 m3 day−1, corresponding to an infiltration rate of 0.2 m day−1, which creates a groundwater mound with a radius of around 500 m from the center of the pool. The groundwater mound also serves as a hydrodynamic barrier, preventing inflow of contaminated groundwater from irrigated fields and rice checks to the pumping wells. The potential rate of groundwater pumping from two water-supply wells can reach up to 7350 m3 day−1 over 10 years, providing a maximum drawdown in the wells of about 24 m. The water required by the Kishi-Tobe settlement can be supplied at a rate of 864 m3 day−1, achieving both available drawdowns by the end of the forecast period and balanced provision of the groundwater resource.