Sustainable Groundwater Decisions: Hydro-Economic Model Applications to Irrigation in Contrasting Environmental Conditions

Boyao Tian , Andrea Brookfield, Margaret Insley, David Rudolph

Groundwater is important for global agriculture but increasing populations and rising food demand are placing significant pressure on its sustainable use for irrigation. Effective, financially viable irrigation management strategies are urgently needed. This study applies a farm-level hydro-economic model to two contrasting sites: the High Plains Aquifer (HPA), a deep, overexploited, unconfined aquifer where overlying regions are almost entirely reliant on groundwater for irrigation; and the Saskatchewan River Basin (SRB), a relatively undepleted basin where overlying regions use both groundwater and surface water for irrigation. The model estimates groundwater availability and long-term land values while accounting for climate change impacts on crop production and irrigation practices. Using Conditional Value-at-Risk to assess economic risks, it offers robust recommendations for sustainable groundwater use. Results demonstrate distinct irrigation strategies: the HPA site faces greater potential economic and environmental impacts and requires increased irrigation to maintain productivity in the future; the SRB site experiences moderate impacts with little change needed to adapt to future climate scenarios. This divergence highlights how climate and water source variability shape trade-offs between economic returns and resource sustainability. This framework provides practical guidance for tailoring irrigation policies to regional conditions while managing risk under uncertain futures.