Simulated changes in ground-water flow caused by hypothetical pumping in east Carson Valley, Douglas County, Nevada

An existing ground-water model of Carson Valley was used to simulate changes in ground-water flow on the east side of Carson Valley, Nevada, in response to hypothetical increases in ground-water pumpage. Pumpage scenarios that reflect State ground-water permits and pending applications were used in four different simulations to estimate the effect of hypothetical development on ground-water levels and storage, ground-water flow to the Carson River, and ground water consumed by evapotranspiration over a 45-year period. The four simulations were based on pumpage rates ranging from 0.13 to 6.4 cubic feet per second (92 to 4,590 acre-feet per year). Changes in ground-water flow and water levels caused by the lowest rate were minimal and at the limit of accuracy of the ground-water model. The highest pumping rate caused water-level declines as much as 15 feet, decreased ground-water storage by 27,000 acre-feet, decreased ground-water flow to the Carson River by 4.3 cubic feet per second (3,100 acre-feet per year), and reduced evapotranspiration losses by about 1,200 acre-feet per year.