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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: 446

Cyanotoxins in the California Sacramento-San Joaquin Delta: Whole Water Cyanotoxin Samples Cyanotoxins in the California Sacramento-San Joaquin Delta: Whole Water Cyanotoxin Samples

This dataset is comprised of cyanotoxin concentrations from whole water cyanotoxin samples collected at water quality stations in the Sacramento-San Joaquin Delta, beginning in 2020. Cyanotoxin congeners were measured from whole water cyanotoxin samples within the cyanotoxin classes: microcystins, anatoxins, cylindrospermopsins, saxitoxins, anabaenopeptins, and nodularin. Concentrations...
By
California Water Science Center

Data for Per- and Polyfluoroalkyl Substances (PFAS) in groundwater samples collected by the California Groundwater Ambient Monitoring and Assessment Priority Basin Project, 2019-2024 Data for Per- and Polyfluoroalkyl Substances (PFAS) in groundwater samples collected by the California Groundwater Ambient Monitoring and Assessment Priority Basin Project, 2019-2024

The California Groundwater Ambient Monitoring and Assessment Program Priority Basin Project (GAMA-PBP) analyzed per-and polyfluoroalkyl substances (PFAS) in groundwater samples collected from domestic and public drinking water supply wells in California. GAMA-PBP is a cooperative program between the U.S. Geological Survey and the California State Water Resources Control Board. This...
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California Water Science Center

California Agricultural Land Use Estimates Derived from Pesticide Use Reporting Data California Agricultural Land Use Estimates Derived from Pesticide Use Reporting Data

Agricultural land use estimates are vital to understanding agricultural production, economic contributions, and water demands. A method to estimate spatially and temporally distributed agricultural land use was developed for California. Pesticide application records were processed to develop annual statewide estimates of agricultural land use at approximately 1-square mile resolution...
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California Water Science Center

Water quality and nutrient data from San Joaquin River and Stockton Waterfront, April and August 2024 Water quality and nutrient data from San Joaquin River and Stockton Waterfront, April and August 2024

This dataset records diel changes to water quality parameters, nutrients, and phytoplankton biomass in the south-eastern region of the Sacramento-San Joaquin Delta. Sampling occurred in August 2024 in the Stockton Waterfront (City of Stockton, San Joaquin County, California, USA) and San Joaquin River. Data was collected from approximately 6am to 9pm Pacific Standard Time on August 6, 13...
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California Water Science Center

Russian River Integrated Hydrologic Model: an integrated hydrology and river operations model used to evaluate water use and climate change scenarios in the Russian River watershed Russian River Integrated Hydrologic Model: an integrated hydrology and river operations model used to evaluate water use and climate change scenarios in the Russian River watershed

The Russian River watershed, situated in coastal, northern California, experiences hydrologic extremes, including periodic droughts and flooding. Water managers are working to maintain sustainable water supplies and environmental flows, while mitigating flood risks. This data release documents an integrated hydrology and river operations model for the Russian River watershed. This model...
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California Water Science Center

Russian River Integrated Hydrologic Model (RRIHM): Streamflow-Routing Package (SFR) Russian River Integrated Hydrologic Model (RRIHM): Streamflow-Routing Package (SFR)

The Russian River Watershed (RRW) covers about 1300 square miles (without Santa Rosa Plain) of urban, agricultural, and forested lands in northern Sonoma County and southern Mendocino County, California. Communities in the RRW depend on a combination of Russian River water and groundwater to meet their water-supply demands. Water is used primarily for agricultural irrigation, municipal...
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California Water Science Center

Russian River Integrated Hydrologic Model (RRIHM): Agricultural Water Use Package (AG) Russian River Integrated Hydrologic Model (RRIHM): Agricultural Water Use Package (AG)

The Russian River Watershed (RRW) covers about 1300 square miles (without Santa Rosa Plain) of urban, agricultural, and forested lands in northern Sonoma County and southern Mendocino County, California. Communities in the RRW depend on a combination of Russian River water and groundwater to meet their water-supply demands. Water is used primarily for agricultural irrigation, municipal...
By
California Water Science Center

Laboratory-based optical measurements for water samples collected from Clear Lake, California Laboratory-based optical measurements for water samples collected from Clear Lake, California

Clear Lake, located within the Coast Range west of California's Central Valley, is the largest natural freshwater lake contained fully within the state. The lake has three arms: a large open-water region to the northwest (Upper Arm), a smaller and narrower region to the southeast (Lower Arm), and the smallest and narrowest region to the east (Oaks Arm). Water quality in Clear Lake is...
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California Water Science Center

Sorption Coefficients (Kd) for Perfluorooctanoic acid (PFOA) and Perfluorooctanesulfonic acid (PFOS), and supporting soil properties at a 250-meter resolution, based on 30-meter resolution data from the Polaris Soils database Sorption Coefficients (Kd) for Perfluorooctanoic acid (PFOA) and Perfluorooctanesulfonic acid (PFOS), and supporting soil properties at a 250-meter resolution, based on 30-meter resolution data from the Polaris Soils database

Per- and polyfluoroalkyl substances (PFAS) chemicals are known to strongly sorb onto soils when being transported downward through the vadose zone. The degree to which this sorption occurs depends on the length of the specific PFAS molecular chain and the properties of the soil. The properties with greatest influence on the soils PFAS sorption potential are percent silt and clay, and...
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California Water Science Center

Water Chemistry Data for Samples Collected at Groundwater Sites in the Santa Fe Springs Oil Field Study Area, April 2021 to April 2024, Los Angeles County, California Water Chemistry Data for Samples Collected at Groundwater Sites in the Santa Fe Springs Oil Field Study Area, April 2021 to April 2024, Los Angeles County, California

The California State Water Resources Control Board (State Water Board) initiated the Oil and Gas Regional Monitoring Program (RMP) to assess effects of oil and gas development on groundwater designated for any beneficial use. The U.S. Geological Survey (USGS) is the technical lead in conducting the RMP through the California Oil, Gas, and Groundwater (COGG) Program, working in...
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California Water Science Center

Data for evaluating sustainable management of groundwater-quality and trends for groundwater basins in the Gilroy-Hollister Valley and northern San Joaquin Valley, California Data for evaluating sustainable management of groundwater-quality and trends for groundwater basins in the Gilroy-Hollister Valley and northern San Joaquin Valley, California

This data release documents five tables and one geographic information systems shapefile feature used to evaluate groundwater quality and concentration trends for groundwater basins in the Gilroy-Hollister Valley and northern San Joaquin Valley, California. This dataset provides a framework for evaluating groundwater quality data at the spatial scale of groundwater basins and the...
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California Water Science Center

Potential Explanatory Variables for Groundwater Quality in California Potential Explanatory Variables for Groundwater Quality in California

This data release codifies and attributes values for potential explanatory factors to groundwater well locations and to groundwater basins in California. The groundwater sites are 282,000 wells that have water-quality data and are listed in the California State Water Resources Control Boards' Groundwater Ambient Monitoring and Assessment Program Groundwater Information System (GAMA GIS)...
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California Water Science Center
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