Development of a Coupled Hydro-Economic Model to Support Groundwater Irrigation Decisions

Abstract

This research develops an integrated hydro-economic modeling framework to support farm-level irrigation decision-making under hydrologic, economic, and climatic uncertainty. The model couples groundwater dynamics, including analytical representations of groundwater-surface water interactions, with crop yield response, and economic valuation to assess trade-offs between agricultural profitability, water use, and long-term sustainability. Conditional Value-at-Risk (CVaR) is incorporated to evaluate downside risk and capture extreme events often overlooked by traditional risk assessment methods. The framework is applied to two contrasting agricultural systems: the High Plains Aquifer (U.S.) and the Saskatchewan River Basin (Canada), representing unconfined and confined aquifers under differing climatic and hydrologic conditions. The results demonstrate that moderate water use strategies often achieve the best balance between profitability and groundwater sustainability, while excessive pumping leads to significant streamflow depletion and reduced long-term benefits. Multi-objective optimization using NSGA-II identifies Pareto-efficient solutions that balance land value, water depth, and streamflow impacts. The model’s simplicity and adaptability make it accessible to farmers, policymakers, and regulators, providing a practical decision-support tool without requiring intensive data or computational resources. Overall, this research contributes to advancing hydro-economic modeling, integrating risk assessment, and promoting sustainable groundwater irrigation management under increasing climate and market variability.