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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: 435

Assessing spatial variability of nutrients, phytoplankton and related water-quality constituents in the California Sacramento-San Joaquin Delta at the landscape scale: 2020-2021 High-resolution mapping surveys Assessing spatial variability of nutrients, phytoplankton and related water-quality constituents in the California Sacramento-San Joaquin Delta at the landscape scale: 2020-2021 High-resolution mapping surveys

The dataset documents the spatial and temporal variability of nutrients, phytoplankton, and related water quality parameters at high spatial resolution in the Sacramento-San Joaquin River Delta and Suisun Bay of California, USA. The dataset includes nitrate, ammonium, orthophosphate, dissolved organic carbon, temperature, conductivity, dissolved oxygen, and chlorophyll as well as...
By
California Water Science Center

Geochemical data for water, sediment, and biota in Lake Combie, California, 2017-2021 Geochemical data for water, sediment, and biota in Lake Combie, California, 2017-2021

This dataset includes field measurements and laboratory analyses of surface water, bottom water (sediment-water interface), surficial (0-2 cm) sediment, pore water (0-2 cm), and biota collected in Lake Combie, California, from September 2017 through August 2021. The study area includes six sites within the reservoir where discrete samples of surface water, bottom water, sediment, and...
By
California Water Science Center

Assessing spatial variability of nutrients, phytoplankton, and related water quality constituents in the California Sacramento-San Joaquin Delta during treated wastewater effluent holds: August and September 2019 high resolution mapping surveys Assessing spatial variability of nutrients, phytoplankton, and related water quality constituents in the California Sacramento-San Joaquin Delta during treated wastewater effluent holds: August and September 2019 high resolution mapping surveys

The study is comprised of daily survey data consisting of high resolution mapping and discrete sample collection of nutrients, phytoplankton, and related water quality constituents conducted in the Sacramento River, Georgiana Slough, and the North and South Forks of the Mokelumne River on August 28 and September 10-12, 2019, coincident with planned holds of treated wastewater effluent...
By
California Water Science Center

Pesticide Concentrations Measured in Zooplankton Samples Collected from the Sacramento River and Yolo Bypass, California, 2021 Pesticide Concentrations Measured in Zooplankton Samples Collected from the Sacramento River and Yolo Bypass, California, 2021

Zooplankton samples were collected at one site upstream of the Yolo Bypass in Northern California, three sites within the Bypass, and at a comparison site on the Sacramento River below the city of Sacramento and analyzed for a large suite of current-use pesticides and degradates. Samples were collected every two weeks from early August 2021 to mid-October 2021. Samples were collected by...
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California Water Science Center

Oil well annular cement and casing damage data in mature oil fields undergoing hydraulic fracturing, South Belridge and Lost Hills Oil Fields, California Oil well annular cement and casing damage data in mature oil fields undergoing hydraulic fracturing, South Belridge and Lost Hills Oil Fields, California

This data release contains oil well annular cement and casing damage data from parts of the South Belridge and Lost Hills Oil Fields in western Kern County, California. The study area coincides with where groundwater with less than 10,000 milligrams per liter total dissolved solids and outside an exempt aquifer are located overlying oil-producing zones in these fields. In the study areas
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California Water Science Center

Groundwater elevation data and models in and around select California oil fields (ver. 3.0, September 2025) Groundwater elevation data and models in and around select California oil fields (ver. 3.0, September 2025)

This data release contains groundwater elevation data and the associated model/code used to create groundwater elevation surfaces in and around select oil fields in California. The data and model provided here are intended to supplement interpretative manuscripts. Specific study areas will be added as Child Items found in this data release. Groundwater elevations are usually collected...
By
California Water Science Center

Attributed California Water Supply Well Completion Report Data for Selected Areas, Derived from CA WCR OSCWR Data (ver. 6.0, December 2025) Attributed California Water Supply Well Completion Report Data for Selected Areas, Derived from CA WCR OSCWR Data (ver. 6.0, December 2025)

This Well Completion Report geospatial dataset represents an index to a subset of records available from the California Department of Water Resources' (DWR) Online System for Well Completion Reports (OSWCR). This version of the release contains data from 292,976 well completion reports (WCRs) for water supply wells from Amador, Butte, Calaveras, Colusa, Contra Costa, El Dorado, Fresno...
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California Water Science Center

Environmental chemistry from selected sites in Lakeport, Lake County, California (version 1.1, August 2023) Environmental chemistry from selected sites in Lakeport, Lake County, California (version 1.1, August 2023)

This data release documents chemical analyses of environmental samples collected by the U.S. Geological Survey (USGS) in Lakeport (Lake County, California) during July 11-12, 2022. Environmental samples were collected at selected sites to assess the effects of lead-based paint on soil chemistry. This sampling was made as part of a broader study to attribute sources of lead in soils in...
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California Water Science Center

Lower Salinas Valley Hydrologic Models: Agricultural and Municipal Water Supply and Groundwater Data (ver. 2.1, August 2024) Lower Salinas Valley Hydrologic Models: Agricultural and Municipal Water Supply and Groundwater Data (ver. 2.1, August 2024)

This digital dataset contains the datasets related to agricultural and municipal water supply and groundwater in the Lower Salinas Valley Hydrologic Models (LSVHM), including the Salinas Valley Operational Model (SVOM) and the Salinas Valley Integrated Hydrologic Model (SVIHM). Groundwater inflow and outflow data include reported groundwater pumpage and groundwater elevations obtained...
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California Water Science Center

Water Quality and Biological Data from Ponds on Islands of the Sacramento-San Joaquin Delta Water Quality and Biological Data from Ponds on Islands of the Sacramento-San Joaquin Delta

This data includes information on water quality, zooplankton, and fish sampled in ponds on delta islands in San Joaquin County, California. The islands include Bacon (North and South ponds), Bouldin (East and West ponds), Holland Tract (Middle, North, and South ponds), and Webb Tract (East, Middle, and North ponds). Discrete water quality parameters were measured bimonthly and continuous
By
California Water Science Center

Model Archive Summary for Turbidity Derived Suspended-Sediment Concentrations at USGS Station 11336680; South Mokelumne River at New Hope Bridge near Walnut Grove, California (2011 - 2015) Model Archive Summary for Turbidity Derived Suspended-Sediment Concentrations at USGS Station 11336680; South Mokelumne River at New Hope Bridge near Walnut Grove, California (2011 - 2015)

Continuous 15-minute time-series suspended-sediment concentration (SSC) data computed from USGS instream turbidity data using a YSI 6-series multi-parameter water quality sonde for the South Mokelumne River at New Hope Bridge near Walnut Grove, California station (SMR; USGS #11336680). A model archive summary describes the development of a continuous 15-minute SSC time-series regression...
By
California Water Science Center

Model Archive Summary for Turbidity Derived Suspended-Sediment Concentrations at USGS Station 11336685; North Mokelumne River near Walnut Grove, California (2011 - 2015) Model Archive Summary for Turbidity Derived Suspended-Sediment Concentrations at USGS Station 11336685; North Mokelumne River near Walnut Grove, California (2011 - 2015)

Continuous 15-minute time-series suspended-sediment concentration (SSC) data computed from U.S. Geological Survey (USGS) instream turbidity data using a YSI 6-series multi-parameter water quality sonde for the North Mokelumne River near Walnut Grove, California, USGS station #11336685. A model archive summary describes the development of a continuous 15-minute SSC time-series regression...
By
California Water Science Center
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