Experimental study on recharge capacity of a mixed well injection in Xi’an

Abstract

The over-exploitation of groundwater can be controlled and prevented by using mixed well to recharge groundwater. A seepage model of semi-confined aquifers was established for simulating recharge well in a cone of depression. Two mathematical expression formulas were proposed for estimating recharge capacity. To analyze the response of recharge capacity, stepwise injections were introduced. It can be pointed out that recharge capacity increases with that of injection flow; moreover, it tends to attenuate during steady injection, which is closely related to injection flow. An attenuation equation of recharge capacity was constructed finally. Recharge capacity was not related to injection mode. The results indicate that under similar conditions, recharge capacity of a mixed well was about one-third of pumping capacity. A minimum value of recharge capacity was maintained with constant injection. Mixed wells were used to recharge and recover groundwater from the cone of depression.