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• Optimized water recharge using infiltration galleries prevents groundwater depletion. • Surrogate-based simulation–optimization developed the recharge management model. • Simulation model output generated the input–output patterns for surrogate models. • Bayesian and ASHA optimizations automatically selected the best surrogate model. • Planned recharge aids optimized water injection and groundwater depletion control. The Mississippi River Valley Alluvial Aquifer (MRVAA) is the main irrigation source for the Lower Mississippi River Basin. Irrigation water abstraction to meet the demands for extensive agricultural practices has contributed to groundwater depletion in this area. A managed aquifer recharge (MAR) approach has been proposed in this geographic location to minimize the impact of pumping on groundwater depletion. However, it is essential to determine the optimal amount of water to be injected through a MAR technique to reduce the decline in groundwater heads. This paper utilizes a coupled simulation–optimization (S-O) approach to estimate the optimal recharge volume into the alluvial aquifer through infiltration galleries. The aquifer processes were simulated using a physically based, three-dimensional finite-difference numerical code, MODFLOW. The MODFLOW model was calibrated and validated using the recharge rates and available groundwater head data for 26 months (27 February 2020 to 27 May 2022). The calibrated and validated models were then deployed within the coupled S-O approach to develop an aquifer recharge management model to estimate optimal groundwater recharge rates to minimize groundwater decline. Computational efficiency of the aquifer recharge management model was achieved using surrogate models that accurately reproduced the groundwater heads calculated by MODFLOW. Our evaluation demonstrates that a planned transient groundwater recharge strategy, obtained as a solution of the surrogate model based coupled S-O approach, is a useful management strategy for optimized water recharge and groundwater depletion control. This study shows the promise of the surrogate model based coupled S-O approach to potentially reduce groundwater depletion in the MRVAA by utilizing optimized recharge rates at the infiltration galleries. This work has potential applications to other aquifers and geographic locations to mitigate groundwater depletion issues due to extensive agricultural practices. [ABSTRACT FROM AUTHOR]

• The counter-demand method effectively simulates water diversion and distribution. • Successfully resolve the simulation of water extraction-conveyance-use in the Karez. • The average annual groundwater overexploitation was 173 million m3 in the ALB. • Excessive extraction of groundwater poses a threat to nature vegetation survival. The long-standing, irrational development and exploitation of water resources in the Aiding Lake Basin (ALB), coupled with excessive groundwater extraction, have led to the gradual depletion of Aiding Lake, the disappearance of Karez wells, the depletion of spring water, and the deterioration of the ecological environment, all of which are serious threats to the economy and survival and welfare of inhabitants. To address the complexities associated with the staggered distribution of natural rivers and artificial canals within the agricultural irrigated region of the ALB, an inverse computation method to gauge canal water requirements was used in building an intelligent simulation of water diversion and conveyance, incorporating different water use methodologies for complex canal systems within the irrigated region. Additionally, this paper characterizes the interaction between the catchment and conveyance section of the Karez wells and the underground aquifer based on the seasonal river module to simulate the entire flow process of the Karez well system, from water extraction and conveyance to groundwater recharge by infiltration. This study presents a coupled simulation model of seasonal river–lake-groundwater interactions in the ALB, where groundwater is simulated under both steady and unsteady flows. The findings indicate that from 2013 to 2022, the annual average groundwater recharge within the ALB was approximately 1.048 billion m3, while the discharge was 1.221 billion m3, with an annual average groundwater overexploitation of 173 million m3. Furthermore, the long-term overexploitation of groundwater has had a direct impact on the ecological environment, resulting in a survival crisis for natural vegetation except in the upper vegetative zone of Aiding Lake, which has good groundwater recharge conditions. [ABSTRACT FROM AUTHOR]