California Water Science Center

Data and Tools

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.

Current California Streamflow Conditions

Current California Streamflow Conditions

Real-time streamflow data from automated equipment, representing the most current hydrologic conditions.

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California Groundwater Quality

California Groundwater Quality

This interactive webmap plots water-quality data from domestic and public-supply wells sampled by the USGS for the California GAMA Priority Basin Project, and allows users to download datasets.

Water Quality Data
Filter Total Items: 181
Date published: January 6, 2020

San Antonio Reservoir, California, bathymetric digital elevation model (DEM), NAVD88, (2018)

Dataset contains reservoir bathymetry collected using multibeam sonar and terrestrial lidar.

Date published: January 6, 2020

San Antonio Reservoir, California, 10-ft contours, NAVD88, (2018)

Dataset contains contours at 10-foot intervals of the San Antonio Reservoir, California, based on the bathymetric survey conducted in April of 2018. Files are provided as geospatial shapefiles and CAD (.dwg file extension) files.

Date published: January 6, 2020

San Antonio Reservoir, California, Stage-area and Stage-volume tables (2018)

Dataset contains a comma delimited (csv) file reservoir stage-area and stage-volume tables. Stage is provided in elevation (in ft NAVD88) in the first column in 0.1 ft increments. Reservoir surface area is in acres and volume in acre-feet at each of those 0.1 foot increments.

Date published: December 31, 2019

Geochemical, mineralogical, and grain-size data for in-situ solid materials and suspended sediment at Malakoff Diggins State Historic Park, Nevada County, California

This dataset includes data for in-situ solid materials and suspended sediments from surface-water samples, as well as surface-water chemistry from samples collected during storm events at Malakoff Diggins State Historic Park, Nevada County, California. In-situ solid samples were collected during 2015 along six vertical transects along the cliff walls of the mine pit. Surface-water samples w...

Date published: December 16, 2019

Pesticide Constituent Data from the California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project (GAMA-PBP), 2004 - 2018

The California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project (GAMA-PBP) submitted 2,994 samples in 2004-2018 to the USGS National Water Quality Laboratory (NWQL) for analysis of pesticide constituents on NWQL schedules 2003, 2032, or 2033, and 840 samples in 2004-2011 for analysis of pesticide constituents on NWQL schedule 2060. Fram and Stork (201

Date published: December 13, 2019

Historical Produced Water Chemistry Data Compiled for the Elk Hills Oilfield, Kern County, California

This dataset contains geochemical and other information for 340 samples of produced water from the Elk Hills Oil Field. Water that is produced as a byproduct of oil production is called produced water. The publicly available produced water chemistry data was compiled by USGS staff using historical DOGGR datasets and scanned images. The data were transferred manually into a numerical dataset...

Date published: December 4, 2019

Gillnet data for fishes of the upper San Francisco Estuary and Sacramento-San Joaquin Delta

This is the data release for gillnet data from a 2016-18 USGS Tidal Wetlands Study and a 2010-11 Sacramento Splittail Study targeting fish in the upper San Francisco Estuary and Sacramento-San Joaquin Delta. This data was used to analyze selectivity parameters of five gillnet mesh sizes (38.1, 50.8, 63.5, 76.2, 88.9 mm) on 15 fish species of the upper San Francisco Estuary and Sacrame

Date published: October 29, 2019

Diets of Striped bass and Sacramento pikeminnow at Ryer Island, Suisun Bay, California, 2018

This data set includes environmental and biological information on fishes collected using gill nets and otter trawls during day and night, as well as diet data for Striped bass and Sacramento pikeminnow obtained via gastric lavage. Sampling took place in and around Ryer Island, Suisun Bay, California during Winter and Spring of 2018.

Date published: October 25, 2019

Sediment Concentration and Velocity Data to Assess Trapping by Submerged Vegetation

The acoustic Doppler current meter (ADCP) used in this study outputs binary data files containing measurement scheme, location, time, velocity, backscatter, boat heading, depth, and other parameters. These data are provided here in the manufacturer's "classic ASCII" format, as described in READMEforADCP.txt file associated with this data release. We also collected water

Date published: October 4, 2019

Dissolved Noble Gas Concentrations and Modeled Recharge Temperatures for Groundwater from Northern Sierra Nevada Foothills Shallow Aquifer Assessment Study Units, 2015-2017: Results from the California GAMA Priority Basin Project

This data release documents 155 sets of dissolved noble gas analyses (neon, argon, krypton, xenon) and 153 modeled recharge temperatures for groundwater sampled from domestic water supply wells and springs throughout the northern Sierra Nevada foothills as part of the California State Water Resources Control Board’s Groundwater Ambient Monitoring and Assessment (GAMA) Progra

Date published: September 26, 2019

Data for assessing the susceptibility of groundwater used for drinking water supply from selected principal aquifers of the Western United States, 2004-2018

Groundwater age distribution and susceptibility to natural and anthropogenic contaminants were assessed for selected principal aquifers of the Western United States: the Central Valley aquifer system (CVAL), the Basin and Range basin-fill aquifers (BNRF), the Rio Grande aquifer system (RIOG), the High Plains aquifer (HPAQ), the Columbia Plateau basaltic-rock aquifers (

Date published: September 12, 2019

Surface Water Quality at Rodeo Lagoon on August 16th, 2016

Field data for a spatial water quality map, using Yellow Spring Instruments (YSI) EXO2 sondes over a span of 160 minutes in Rodeo Lagoon, CA, on August 16th, 2016. This data release includes all measured environmental parameters included in the analysis.