Process Based Integrated Models for Managed Aquifer Recharge and Aquifer Storage Treatment and Recovery

Process based semi-analytical models for surface and ground water management of a recharge basin, based on the concept of managed aquifer recharge (MAR) and aquifer storage treatment and recovery (ASTR), are presented. The model for simulation of aquifer responses due to recharge and extraction of recharged water is developed by integrating the hydrologic components into basic water balance equation; and the models for simulation of contaminants' fate in the recharge basin and through the soil column beneath are developed by considering: (i) in-basin mass balance with decay of contaminant and, (ii) 1-dimensional advection-dispersion-decay equation coupled with linearized sorption isotherm equation, respectively. The estimate of hydrologic components included: inflow to the recharge basin from its catchment by SCS-CN model, water surface evaporation by combination of Priestley-Taylor and Penman method, recharge by Hantush's analytical equation for water table rise due to recharge from a rectangular spreading basin in absence of pumping well, and drawdown due to pumping by Theis's well function equation. The contaminant's fate estimate included: time varying changes in concentration due to assimilation and detention of contaminant in the recharge basin and transport of assimilated materials through saturated soil column until they reached the groundwater table. The performances of recharge-pumping and contaminants' transport models are illustrated by examples. These models can successfully be used and upscale as potential tools for MAR and ASTR.