UTAH GEOLOGICAL SURVEY'S WEST DESERT GROUND-WATER MONITORING PROJECT

In response to increased current and future demand on water resources in Utah's west desert, the Utah Geological Survey has undertaken a large-scale ground-water monitoring-well drilling project to establish baseline conditions and better understand local and regional ground-water flow systems. Currently, we have 64 new piezometers located at 26 sites throughout Snake Valley and in surrounding valleys. Wells are in the basin-fill and carbonate aquifers, and are located along range fronts, basin centers, and at regional discharge areas. The majority of these have been sampled for chemical data. We also have over 50 transducers and barometric loggers installed both in our wells and in previously existing wells. Future work includes installing discharge gages at several regional springs, additional chemical sampling with the USGS, and conducting two aquifer tests, with additional drilling added as funding allows. Water levels confirm the potential for regional northeast ground-water flow for over 100 miles from the recharge area along the eastern flank of the Snake Range in Nevada to the main regional discharge point at Fish Springs National Wildlife Refuge. Preliminary data show progressive chemical evolution toward Na-Cl, higher TDS, and warmer water from SW to NE along the regional flow path. Modern ground-water ages are found in the upper 100 feet of the alluvial aquifer and in both aquifers near range fronts. Mixed modern and ancient ground-water ages are found deeper in basin centers, in the carbonate aquifer far from the recharge area, and at regional springs.