Planning sustainable optimal groundwater yield for the Utah part of Cache Valley

SOMO1, a simulation/optimization model for groundwater development, is used to compute sustainable optimal groundwater yield pumping strategies for the Utah part of Cache Valley. SOMO1 employs the response matrix method of representing system response to stimuli as constraint equations within an optimization problem. Maximum sustained yield pumping strategies are computed for three groups of optimization scenarios. Each group has a different set of constraints (restrictions). Scenarios considered new candidate well locations for each municipality. Results show that maximum sustainable pumping could be as much as 38% greater than the non-optimal steady state pumping of 1990, if applying the most relaxed set of constraints. The optimal pumping rates are very sensitive to river/aquifer seepage. Another scenario applies the most restrictive seepage constraints while examining the possibility of increasing pumping from existing wells rather than constructing new wells.