Water Quality

Migratory wildlife need to balance the benefits of migration and reproduction with the physiological costs. This is particularly challenging in dynamic environments like wetlands, where food levels can vary greatly from year to year. For shorebirds in the Great Basin region, saline or terminal lakes provide essential habitats during their annual life cycle. To understand how changes in hydrology...

The USGS Nevada Water Science Center is collaborating with the Bureau of Land Management and PolyAnalyltik Laboratory in Ontario, Canada to evaluate the potential migration of butyl acrylate vinyl acetate (dust palliative) in soil and storm runoff from areas of application in southern Nevada. There is concern regarding the exposure of the desert tortoise and other wildlife to palliative chemicals...

The Lake Tahoe Interagency Monitoring Program (LTIMP) is an essential part of integrated science in the Lake Tahoe Basin and has provided long-term, consistent, reliable, and accessible tributary monitoring data for decades.

The Colorado River is one of the most intensely used rivers in the western United States, providing recreational watercraft activities and domestic drinking, industrial, and irrigation water for over 22 million users in the desert southwest. The quality of this water must be maintained to guarantee a reliable and safe resource for its many uses. The Colorado River provides an estimated 97 percent...

From 2007 to 2021, the U.S. Geological Survey (USGS) collaborated with the Nevada Bureau of Mines and Geology on evaluating the forms of arsenic in Nevada groundwater resources. A total of 190 groundwater samples were collected from wells and springs throughout Nevada. Concentrations of arsenic ranged from <1.6 to 2,408 micrograms per liter (µg/L); in most cases, arsenate was the dominant species...

Periphyton, a type of algae, is growing on bottom sediment and rocks along nearshore areas of Lake Tahoe. Periphyton is seen as a nuisance and negatively impacts the recreational value of the lake. Periphyton biomass (PB) data collected along the nearshore of Lake Tahoe exhibit increasing trends over the last decade. However, the mechanisms that have caused these changes are not well understood.

USGS Nevada Water Science Center (NVWSC) is sampling for Volatile Organic Compounds (VOCs) in 2019 in order to confirm previous data collection efforts at Lake Tahoe. The Tahoe Regional Planning Agency (TRPA) requested sampling in targeted locations and at times when petroleum constituents are most likely to be detected in the lake.

Since the late 1980’s, the USGS has collected discharge, sediment, and water quality data at seven major drainages under the Lake Tahoe Interagency Monitoring Program (LTIMP). Recently, continuous, real-time measurements of turbidity were added to the LTIMP. These data can be combined with in situ, model simulations, and remotely-sensed datasets available from the USGS, National Aeronautics and...

High concentrations of phosphorus (P) and nitrogen (N) are responsible for excessive, or nuisance algal blooms in many ecosystems world-wide, and climate change is predicted to exacerbate the problem1,2. Excessive nutrients supplied to the nearshore zone of Lake Tahoe may have significant consequences to ecological communities, water clarity, and water quality. The nearshore zone represents the...

The Nevada Water Science Center (NVWSC) is increasing the spatial understanding of the distribution of arsenic and important geochemical information in groundwater resources near select water-supply wells in southern Carson Valley by collecting groundwater samples to complement the existing dataset (2006 – 2015).

The USGS Nevada Water Science Center (NVWSC), in partnership with the National Park Service (NPS), is evaluating and monitoring the basic water quality and sediment chemistry of two proposed refugia and three established habitats for the endangered Mohave Tui Chub over the course of the year. NVWSC will also compare and evaluate findings to U.S. Environmental Protection Agency screening levels and...

The USGS Nevada Water Science Center (NVWSC), in collaboration with the U.S. Environmental Protection Agency (EPA), monitored mercury in the Carson River from 1997 to 2013. To preserve this long-term dataset, NVWSC is monitoring mercury concentrations and suspended sediment in the Carson River above and below Lahontan Reservoir. NVWSC also is beginning process-based sampling above and below...