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Data

Providing current data for analysis, forecasting, and research

Providing current data for analysis, forecasting, and research

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

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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

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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

California Water Data

Filter Total Items: 434

Insecticide and fungicide concentrations in irrigation runoff and soils from a lettuce field in the Salinas Valley, California, 2019 and 2020 Insecticide and fungicide concentrations in irrigation runoff and soils from a lettuce field in the Salinas Valley, California, 2019 and 2020

Irrigation runoff and soil samples were collected from a lettuce field located at the USDA-ARS Spence Research farm in the Salinas Valley, California to measure neonicotinoid insecticides (clothianidin and imidacloprid) and a fungicide (azoxystrobin) applied via coated seed and drench treatments. The field trial was designed to evaluate four treatments with replication: 1) control...
By
California Water Science Center

High-Resolution Measurements to Identify Effects of Aquatic Vegetation on Water Quality and Stratification High-Resolution Measurements to Identify Effects of Aquatic Vegetation on Water Quality and Stratification

The dataset documents the spatial and temporal variability of nutrients and related water quality parameters at high spatial resolution in the North Delta of the Sacramento-San Joaquin River Delta of California, USA. The dataset includes surface mapping, depth profile, and discrete data for nitrate, ammonium, phosphate, dissolved organic carbon, temperature, conductivity, dissolved...
By
California Water Science Center

Water chemistry data for samples collected at groundwater sites near the Oxnard oil field, June 2017-August 2017, Ventura County, California 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. Groundwater samples were collected from one public supply well, four monitoring wells, and nine irrigation wells located within a three-...
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California Water Science Center

Database of Geomorphic Features, Klamath River, California 2010 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. The physical response of the Klamath River...
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California Water Science Center

Diets and Stable Isotopes of Fishes in Rodeo Lagoon, California, 2016-2017 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.
By
California Water Science Center

The Basin Characterization Model - A monthly regional water balance software package (BCMv8) data release and model archive for hydrologic California (ver. 5.0, June 2025) The Basin Characterization Model - A monthly regional water balance software package (BCMv8) data release and model archive for hydrologic California (ver. 5.0, June 2025)

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 2024. The BCMv8 was refined from the previous BCMv65 version to improve the accuracy of the water-balance components
By
California Water Science Center

Electrical Resistivity Tomography Data at Elizabeth Lake, Los Angeles County, California, 2019 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...
By
California Water Science Center

Inorganic chemistry data for groundwater wells near selected oil fields in the southwestern San Joaquin Valley, central California Inorganic chemistry data for groundwater wells near selected oil fields in the southwestern San Joaquin Valley, central California

This digital dataset contains geochemical and other information for 1,209 samples of groundwater from 343 wells located within 3-miles of the Buena Vista, Elk Hills, Midway-Sunset, and North and South Coles Levee oil fields in the southwestern San Joaquin Valley of central California. Data were compiled by the U.S. Geological Survey (USGS) from preexisting datasets and transferred...
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California Water Science Center

Zooplankton Survey of the Northern Sacramento-San Joaquin Delta, California, 2016-2018 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 102um mesh. Samples were preserved in the field in 10...
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California Water Science Center

California Groundwater Ambient Monitoring and Assessment (GAMA) Program Domestic-Supply (Shallow) Aquifer Assessment Study Unit Boundaries and Grid Cells for Assessment of Groundwater Resources (ver. 3.0, July 2025) California Groundwater Ambient Monitoring and Assessment (GAMA) Program Domestic-Supply (Shallow) Aquifer Assessment Study Unit Boundaries and Grid Cells for Assessment of Groundwater Resources (ver. 3.0, July 2025)

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...
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California Water Science Center

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

SAR 2018 Native Fish Population and Habitat Study, Santa Ana and San Gabriel Rivers, California SAR 2018 Native Fish Population and Habitat Study, Santa Ana and San Gabriel Rivers, California

This dataset includes 2018 reach fish data and reach habitat data collected to support development of the upper Santa Ana River Habitat Conservation Plan for the Santa Ana Sucker (Catostomus santaanae) and the Arroyo Chub (Gila orcutti) in the Santa Ana and San Gabriel Rivers, California.
By
California Water Science Center
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