Optimal investment in reservoirs and tail-water recovery for economic returns and groundwater conservation.
We examine the economic effectiveness of conjunctive water management with on-farm reservoirs and tail-water recovery to address groundwater scarcity in the Mississippi River Delta region of Arkansas. We find that reservoirs should be built when the depth to the aquifer exceeds 60 feet, and the average share of productive land in a reservoir should be about 2%. Soybean intensive areas use reservoirs sparingly to support shallow groundwater pumping depths, but groundwater remains the primary source of irrigation. Rice intensive areas use reservoirs to supplant groundwater with reservoir surface water when the depth to groundwater increases.