Water Quality

Over the last several decades, both the incidence of large wildfires and the duration of the wildfire season across much of the United States have increased (Westerling and others, 2006, American Water Works Assn, 2008; Finco and others, 2012). Future wildfire projections based on forecasted climate scenarios indicate both an increase in the expected severity of wildfires, and an expansion of...

As part of the Urban Waters Federal Partnership (UWFP), this project will enhance water-quality monitoring on a reach of the Los Angeles River slated for revitalization. The UWFP reconnects urban communities—particularly those that are overburdened or economically distressed—with their waterways by improving coordination among federal agencies.

The effect of selenium toxicity on wildlife has been known for more than 50 years. This issue drew particular attention in the 1980s when embryo deformity and mortality was observed in birds at a wildlife refuge in California. Harmful effects from selenium were determined to be connected to irrigation drainage water. As a result, an effort began to monitor levels of selenium in irrigation drainage...

John Izbicki, PhD, a Research Hydrologist with the U.S. Geological Survey (USGS) California Water Science Center (CAWSC), led a five-year scientific study to determine the range of natural and anthropogenic (human-caused) hexavalent chromium concentrations, also referred to as chromium-6 or Cr(VI), in Hinkley Valley. The study was cooperatively funded by the Lahontan Regional Water Quality Control...

Drought is making the Delta Saltier. Less freshwater coming from watershed runoff and reservoir releases means that more salty water flows into the Sacramento San Joaquin Delta (Delta) from the Pacific Ocean. Changes in Delta salinity have far-reaching impacts, affecting the water supply for agriculture, drinking, wildlife, and Delta ecosystems.

The USGS California Water Science Center conducts a variety of research activities at Clear Lake, California, including surface-water monitoring and water quality and aquatic habitat studies.

The USGS seeks to increase understanding of the groundwater system in the vicinity of the Lower Colorado Water Supply Project well field and to estimate future groundwater levels and total dissolved solids concentrations in the wells and the long-term viability of the Lower Colorado Water Supply Project.

Keswick Reservoir, on the Sacramento River, receives both water and contaminants from the Spring Creek Debris Dam. The term contaminants refers here to different kinds of chemicals that are in some instances delivered to lakes and rivers. These chemicals can have a detrimental effect on drinking water supplies and the health of humans, fish, and other aquatic species.

The Biogeochemistry (BGC) Group uses an interdisciplinary approach to address surface water quality issues and food web dynamics throughout California, particularly in the Sacramento-San Joaquin Delta and San Francisco Bay.

The San Francisco Bay and Sacramento-San Joaquin Delta form one of the largest estuaries in the United States. Water flow and water quality in the San Francisco Bay-Delta Estuary are important to the economies of both California and the nation. The Bay-Delta system provides water to more than 25 million California residents and vast farmlands, as well as key habitat for birds, fish, and other...

Sediments represent an important pool of nutrients in the Sacramento-San Joaquin Delta (Delta). The exchange of nutrients between the water column and the benthos impacts water quality and effects phytoplankton, harmful algal blooms, aquatic vegetation, and drinking water quality. To date, there is very limited information about nutrient pools in Delta sediments, nor how these nutrients are...

Sediment supply is important to the health of the Sacramento-San Joaquin River Delta and San Francisco Bay (Bay-Delta) ecosystem. Sediment eroded from upland source areas in the Sacramento and San Joaquin watersheds is transported through the rivers to the Bay-Delta where it is deposited in mudflats and tidal wetlands, which in turn helps protect against the effects of sea-level rise. Sediment...