Rapid population growth in Carson Valley, west- central Nevada, requires a dependable municipal water source. Artificial recharge of aquifers using available flow of the Carson River is one way to increase the amount of water in underground storage and maintain a dependable ground-water supply. Ground water can be artificially recharged by routing excess surface water or, after proper treatment, routing wastewater to infiltration basins or injection wells. Withdrawal wells would remove stored water when needed. As a first step, maps showing areas in Carson Valley with high, low, moderate and unknown potential for artificial recharge were developed on the basis of the distribution of geologic units, depth to water, specific yield, infiltration rate, and location of natural recharge and discharge. For recharge by means of infiltration, areas totaling 5,700 acres have high potential, 23,900 acres have moderate potential, and 6,200 acres have low potential. For recharge through injection, areas totaling 7,800 acres have high potential and 43,500 acres have moderate potential; 23,000 acres have unknown potential because data are lacking on subsurface conditions. A ground-water-flow model was used to assess the possible results of artificial recharge. Simulations with no accompanying ground-water withdrawal show that, when recharge by injection is simulated near the valley floor, heads in the semiconfined aquifer increase over much of the valley, floor; only about 20 percent of the recharged water is stored in the aquifer after 5 years and as much as 80 percent is lost to streamflow and evapotranspiration. When recharge is simulated on the eastern side of the valley, 80 percent of the recharged water remains in storage after 5 years. When recharge is simulated near the valley floor, more water is lost to discharge than when recharge is on the eastern side of the valley. When recharge is applied for long periods without accompanying withdrawal, recharged water moves downgradient to discharge areas. The recharge water that discharges to the surface-water system could in turn replenish base flow of the Carson River and benefit downstream users.
Additional Publication Details
USGS Numbered Series
Potential for, and possible effects of, artificial recharge in Carson Valley, Douglas County, Nevada
Water-Resources Investigations Report
87 p.; 7 maps on 4 sheets : col. ; 37 x 27 cm., sheets 61 x 102 cm., folded in envelope 30 x 24 cm.