California Water Science Center

Measuring and Monitoring

Basic hydrologic data collection, processing, analysis, dissemination, and archiving are major parts of the California Water Science Center program. Streamflow data, for example, are used for flood and water-supply forecasts, planning and design, river regulation, streamflow statistics, and research investigations. Much of the data are available on a near-real-time basis by satellite telemetry.

Filter Total Items: 146
Date published: June 1, 2021
Status: Active

Biogeochemistry Group

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.

Date published: April 13, 2021
Status: Active

Continuous, Real-Time Water-Quality Monitoring of the Los Angeles River

As part of the Urban Waters Federal Partnership (UWFP) program, this project will bring enhanced water-quality monitoring to a stretch of the Los Angeles River slated for revitalization. The UWFP reconnects urban...

Contacts: Gregory Mendez
Date published: March 4, 2021
Status: Active

State of the Network: Long-Term, High-Frequency Flow and Water Quality Data in the San Francisco Estuary, California

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...

Date published: February 16, 2021
Status: Active

Scotts Creek Nutrient Erosion Study, Lake County, California

Clear Lake, the largest natural lake entirely within California, has a severe problem with harmful algal blooms which can be detrimental to aquatic life by depriving it of oxygen when the algae dies, sinks, and decays. A driving factor of these conditions are the nutrient loads being carried into the lake by soil erosion and...

Date published: November 2, 2020
Status: Active

Selenium Hazard in the Salton Sea Environment, Summary of Current Knowledge to Inform Future Science

The effect of selenium (Se) toxicity on wildlife has been known for more than 50 years. The threat of Se contamination gained greater attention from federal agencies in the 1980s due to the observation of embryo deformity and mortality in birds at a National Wildlife Refuge in California. Harmful effects from Se were determined to be connected to irrigation drainage water.

As a result,...

Date published: September 9, 2020
Status: Completed

Soil moisture datasets at five sites in the central Sierra Nevada and northern Coast Ranges, California

Soil moisture is a critical variable for understanding the impacts of drought on ecological, hydrological, and agricultural systems, as soil moisture content has a direct affect on runoff amounts. Runoff occurs as the result of precipitation (both rainfall and snowfall) that is in excess of the demands of evaporation from land surfaces, transpiration from vegetation, and infiltration into...

Contacts: Michelle Stern
Date published: August 26, 2020
Status: Active

High Resolution Temporal and Spatial Mapping of Mercury and Methylmercury in Surface Waters of the Sacramento – San Joaquin Delta

Mercury (Hg) is a contaminant of significant concern in the San Francisco Bay-Delta estuary and watershed (Bay-Delta). The formation, fate, and transport of methylmercury (MeHg), a particularly toxic organic form of Hg that readily bioaccumulates in wildlife, has been studied extensively throughout the system. However, there is widespread recognition of the need for more comprehensive...

Date published: August 5, 2020
Status: Active

Evaluating the effects of wastewater-derived nutrients on phytoplankton abundance and community structure in the San Francisco Estuary and Delta

Planned upgrades to the Sacramento Regional wastewater treatment plant (SRWTP) will substantially reduce nutrient discharge and also alter the types and amounts of nutrients being distributed across the San Francisco Delta and Estuary (Delta).

One highly anticipated outcome of lower nutrients is improved productivity in the phytoplankton communities that supply aquatic food webs, which...

Date published: July 15, 2020
Status: Active

Modeling Nitrogen Reduction Benefit to Invasive Aquatic Vegetation vs. Native Phytoplankton

Phytoplankton comprise the bottom of the aquatic food web and the abundance of phytoplankton serves as an indicator of healthy aquatic habitats. In the Sacramento-San Joaquin River Delta (Delta), competing with phytoplankton for required nitrogen, invasive aquatic vegetation (IAV) has increased exponentially in recent years. Once established, IAV can negatively impact local ecosystems and...

Date published: June 9, 2020
Status: Active

Effects of Wildfire and Fire Retardants on Nutrient Transport in California Watersheds

Large wildfires have increased in size and frequency in the western United States over the past several decades. This has led to increased soil erosion and the transport of sediment containing nutrients into streams and reservoirs. Excess nutrients typically lead to the increased production of algae which can then lead to low levels of dissolved oxygen. This degrades the habitat for fish and...

Date published: April 8, 2020
Status: Active

Evaluation of Groundwater Resources in the Adelaida Area of San Luis Obispo County, California

Stakeholders in San Luis Obispo County are concerned that the increased demand for water use has, and will continue to, affect groundwater levels and availability in the Adelaida area. To address stakeholder concerns, the County of San Luis Obispo Board of Supervisors has asked the USGS to conduct a comprehensive evaluation of groundwater resources of the Adelaida area. 

Date published: February 18, 2020
Status: Active

Evaluation of groundwater resources of the Anza-Terwilliger area, Anza, California

Groundwater is the sole source for water use to the rural community and two Native American tribes in the Cahuilla Valley and Terwilliger Valley groundwater basins, which are located approximately 35 miles southwest of Palm Springs, California. The characteristics and sustainable yield of the basins are not well understood and are threatened by increasing water use and potential changes in...