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.

California Water Dashboard

California Water Dashboard

View California's real-time stream, lake, reservoir, precipitation, water quality, and groundwater stations in context with current weather and hazard conditions.

Current Conditions

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: 292
Date published: February 8, 2021

Water chemistry data for samples collected at groundwater sites near the Oxnard oil field, June 2017-August 2017, Ventura County, California

In cooperation with the California State Water Resources Control Board's oil and gas Regional Monitoring Program, the U.S. Geological Survey collected and analyzed groundwater and associated quality control (QC) samples during June 2017 - August 2017.

Date published: January 26, 2021

Database of Geomorphic Features, Klamath River, California 2010

The USGS, in cooperation with the U.S. Fish and Wildlife Service and the National Fish and Wildlife Foundation, compiled a map of geomorphic features along a 140-km segment of the main stem Klamath River below Iron Gate Dam, CA. Flood disturbance within the study reach is produced by the combined effect of natural flows and reservoir releases.

Date published: January 25, 2021

Diets and Stable Isotopes of Fishes in Rodeo Lagoon, California, 2016-2017

This dataset includes lab data for fish, fish diets, and stable isotopes for fish tissue, vegetation, and invertebrates collected during daylight hours in the Rodeo Lagoon and Lake in Golden Gate National Recreation Area at the Pacific Coast, USA during 2016 and 2017. This data release includes all animal taxa, and isotope values included in the analysis.

Date published: January 25, 2021

The Basin Characterization Model - A regional water balance software package (BCMv8) data release and model archive for hydrologic California, water years 1896-2020

This data release accompanies the USGS Techniques and Methods report titled: "The Basin Characterization Model - A Regional Water Balance Software Package", and includes all necessary Basin Characterization Model version 8 (BCMv8) inputs and outputs for water years 1896 to 2020. The BCMv8 was refined from the previous BCMv65 version to improve the accuracy of the water-...

Date published: January 21, 2021

Hydrogeology of the Adelaida Area, San Luis Obispo County, CA

The USGS is conducting a comprehensive evaluation of groundwater resources of the Adelaida area. Use this map to explore the hydrogeology of the area, including land use, geology, and USGS hydrologic data by watershed or water management district. 

Date published: January 19, 2021

Electrical Resistivity Tomography Data at Elizabeth Lake, Los Angeles County, California, 2019

The Santa Clara River Lakes, located along the San Andreas fault 19 miles northwest of Palmdale, California, were placed on the state’s “303(d) List” or “Impaired Water List” in 1996 for eutrophic conditions, high pH, and low dissolved oxygen. In 2016, the state adopted a Total Maximum Daily Load (TMDL) for nutrients (nitrogen and phosphorus) in the Santa Clara River Lakes. This study focuses...

Date published: December 28, 2020

California Groundwater Ambient Monitoring and Assessment (GAMA) Program Shallow Aquifer Assessment Study Unit Boundaries and Grid Cells for Assessment of Groundwater Resources

The California Groundwater Ambient Monitoring and Assessment Program (GAMA) is a statewide assessment of groundwater quality designed to help better understand and identify risks to groundwater resources. GAMA is implemented by the California State Water Resources Control Board. The U.S. Geological Survey (USGS) is the technical lead for the Priority Basin Project (PBP), one of the

Date published: December 28, 2020

California Groundwater Ambient Monitoring and Assessment (GAMA) Program Shallow Aquifer Assessment Study Unit Boundaries and Grid Cells for Assessment of Groundwater Resources

The California Groundwater Ambient Monitoring and Assessment Program (GAMA) is a statewide assessment of groundwater quality designed to help better understand and identify risks to groundwater resources. GAMA is implemented by the California State Water Resources Control Board. The U.S. Geological Survey (USGS) is the technical lead for the Priority Basin Project (PBP), one of the

Date published: December 28, 2020

Zooplankton Survey of the Northern Sacramento-San Joaquin Delta, California, 2016-2018

This data set contains information on zooplankton and associated environmental parameters for sampling conducted in California's northern Sacramento-San Joaquin Delta between May 2016 and April 2018. Macrozooplankton were sampled with horizontal tows (water surface) of a 50 cm-diameter conical plankton net that was 150cm long with 102µm mesh. Samples were preserved in the field in 10%

Date published: December 22, 2020

Potential Explanatory Factors for Groundwater Quality in the Northern Sierra Nevada Foothills Domestic-Aquifer Assessment Study Units, 2015-2017: California GAMA Priority Basin Project

This data release codifies and attributes explanatory factors that could potentially impact groundwater quality at 142 groundwater sites (wells or developed springs) used for domestic water supply and 310 groundwater sites used for public water supply in the northern Sierra Nevada foothills. Water quality from domestic groundwater sites was assessed as part of the California State Water Resou...

Date published: December 14, 2020

Model archive for analysis of long-term annual yields of highway and urban runoff in selected areas of California with the Stochastic Empirical Loading and Dilution Model (SELDM)

This model archive describes approaches used by the U.S. Geological Survey in cooperation with CalTrans for assessing long-term annual yields of highway and urban runoff in selected areas of California with version 1.1.0 of the Stochastic Empirical Loading and Dilution Model (SELDM). 

Date published: November 25, 2020

Aquifer test data for the Belridge multiple-well monitoring site (BWSD), Kern County, California

To determine aquifer characteristics, pneumatic slug tests were performed on selected zones and aquifers at a monitoring site near the North and South Belridge oil fields in the Southern San Joaquin Valley in Kern County. On November 19th and 20th, 2018, pneumatic slug tests were performed at five monitoring wells located at the multiple-well groundwater-monitoring site BWSD (28S/21E-08