A preliminary evaluation of the chemical character of water near the northwest shore of Topaz Lake, Douglas County, Nevada

The potential for intensive development of land in the study area has raised concern regarding the possible effect of septic-tank effluents on the quality of local ground waters and the lake. Analyses of samples from 13 wells, one spring, the lake, and an inflowing creek were examined for trends in chemical composition. Sampled ground waters from sites upgradient in the hydrologic system have higher concentrations of sulfate and dissolved solids than ground waters near the creek and the lake. Preliminary data suggest that the ground-water reservoir in downgradient areas is locally recharged by the creek and perhaps by the lake. Additional data on both ground-water levels and quality would be required to further define the hydrologic system.