Field investigation of aquifer storage and recovery (ASR) technique to recharge groundwater: a case study in Punjab province of Pakistan

Fast decline of groundwater levels in Pakistan requires the use of artificial recharging techniques to minimize the adverse effect of over pumping. A study was conducted in the Toba Tek Singh district, Punjab, Pakistan, to investigate aquifer storage and recovery (ASR) technology to recharge groundwater. The facility was developed by drilling a pumping/injection well and constructing the water storage tank along with developing the recharge mechanism. Three treatments of 51, 71, and 99 m(3) of treated canal water were injected into the aquifer under gravity and were retained for 7 days. Another three treatments of 100 m(3) each were injected for retention times of 14, 28, and 56 days. The recovery efficiency (RE) was found to be 83, 91, and 98% for injected volumes of 51, 71, and 99 m(3), respectively, for retention time of 7 days. Similarly, the RE for an injected volume of 100 m(3) was found to be 73, 62, and 52% for retention times of 14, 28, and 56 days, respectively. These results indicated that RE improved with increase in injected volume and decreased with increase in retention time; however, the technology was found to have potential for storing and recovering of water injected into the aquifer.