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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: 439

Produced water chemistry data collected from the Oxnard Oil Field, Ventura County, and the Placerita Oil Field, Los Angeles County, 2018, California Produced water chemistry data collected from the Oxnard Oil Field, Ventura County, and the Placerita Oil Field, Los Angeles County, 2018, California

The U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board collected produced water and gas samples in the Oxnard Oil Field in Ventura County in August 2018 and the Placerita Oil Field in Los Angeles County in December 2018. Sampled sites included oil wells; injectate from tanks, pipelines, and injection wells where produced water from many...
By
California Water Science Center

Optical measurements for surface water samples collected within the Neshaminy Creek basin during November 2021 Optical measurements for surface water samples collected within the Neshaminy Creek basin during November 2021

Here we report optical data collected as part of a collaborative study between USGS Pennsylvania Water Science Center, Pennsylvania Department of Environmental Protection and Water Mission Area Proxies Project. The optical measurements reported here were collected to aide in the characterization of water sources and mixtures and establish proxies (surrogates) for per- and poly...
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California Water Science Center

Geochemical data for water, sediment, and biota in areas affected by historical mining, northwestern Sierra Nevada and Trinity Mountains, California Geochemical data for water, sediment, and biota in areas affected by historical mining, northwestern Sierra Nevada and Trinity Mountains, California

This dataset includes data for water, sediment, and biota samples collected at 250 locations in the northwestern Sierra Nevada and the Trinity Mountains during 1999–2012. The locations were chosen to assess potential effects from historical mining, with a focus primarily on mercury contamination associated with placer gold mines in the Sierra Nevada and the Trinity Mountains, and a hard...
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California Water Science Center

Geochemical data for post-fire surface water, streambed sediment, and soils from areas affected by the 2018 Camp Fire, Butte County, California Geochemical data for post-fire surface water, streambed sediment, and soils from areas affected by the 2018 Camp Fire, Butte County, California

During November 2018, the Camp Fire burned more than 150,000 acres in Butte County, California. The fire was the deadliest and most destructive in California history, destroying more than 18,000 structures and causing at least 85 fatalities. The U.S. Geological Survey sampled surface water in areas affected by the Camp Fire, plus an unburned control site, during two post-fire sampling...
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California Water Science Center, Geosciences and Environmental Change Science Center, Denver Radiogenic Isotope Lab

Pesticides in small volume plasma samples Pesticides in small volume plasma samples

Pesticides are widely applied and can enter the environment, potentially effecting non-target organisms. To better evaluate pesticide exposure using non-lethal techniques, a method was developed for the extraction of pesticides and their degradates from small (100 µL) volume plasma samples. Solid phase extraction was used for lipid removal after plasma samples were protein precipitated...
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California Water Science Center

Groundwater-quality data in the Gilroy Hollister basin and surrounding areas Domestic-Supply Aquifer Study Unit, 2022: Results from the California GAMA Priority Basin Project Groundwater-quality data in the Gilroy Hollister basin and surrounding areas Domestic-Supply Aquifer Study Unit, 2022: Results from the California GAMA Priority Basin Project

The U.S. Geological Survey collected groundwater samples from 33 wells used for domestic and small system drinking water supplies in Santa Clara and San Benito Counties, California in 2022. The wells were sampled for the Gilroy Hollister basin and surrounding areas Domestic-Supply Aquifer Study Unit of the State Water Resources Control Board Groundwater Ambient Monitoring and Assessment...
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California Water Science Center

Turbidity and Suspended Sediment Concentration Data from a Laboratory Mixing Tank Experiment 2023 (ver. 1.1, November 2024) Turbidity and Suspended Sediment Concentration Data from a Laboratory Mixing Tank Experiment 2023 (ver. 1.1, November 2024)

Four dams on the Klamath River that created Iron Gate Reservoir and Copco Lake in Siskiyou County, California, and John C. Boyle Reservoir, in Klamath County, Oregon, are scheduled for removal in early 2024. The U.S. Geological Survey (USGS) will deploy high-range turbidity sensors to compute continuous suspended sediment concentration (SSC) before, during, and following the scheduled...
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California Water Science Center

Analysis of Polyphenols in Water Primrose (Ludwigia hexapetala) Plants from the Sacramento-San Joaquin Delta of California Analysis of Polyphenols in Water Primrose (Ludwigia hexapetala) Plants from the Sacramento-San Joaquin Delta of California

Water primrose (Ludwigia hexapetala) is an invasive aquatic plant that has rapidly increased in coverage throughout the Sacramento-San Joaquin Delta. Water primrose has invaded wetlands and may contribute towards mortality of tules (Schoenoplectus spp.) and cattails (Typha spp.). Little research has been completed on the mechanisms responsible for marsh loss, but previous studies have...
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California Water Science Center

Water chemistry data for samples collected at groundwater sites in the Santa Maria Valley Oil Field study area, July 2018–March 2019, Santa Barbara County, California Water chemistry data for samples collected at groundwater sites in the Santa Maria Valley Oil Field study area, July 2018–March 2019, Santa Barbara 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

Water Chemistry data for samples collected at groundwater sites in the Poso Creek Oil Field study area, February 2020-December 2021, Kern County, California Water Chemistry data for samples collected at groundwater sites in the Poso Creek Oil Field study area, February 2020-December 2021, Kern 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

Geochemical and mineralogical data for mine waste from Sulphur Bank Mercury Mine, Lake County, California (ver. 2.0, February 2026) Geochemical and mineralogical data for mine waste from Sulphur Bank Mercury Mine, Lake County, California (ver. 2.0, February 2026)

This data release presents geochemical and mineralogical data for mine waste at Sulphur Bank Mercury Mine (SBMM). This work is performed in cooperation with the US Environmental Protection Agency (EPA) to characterize sources of contamination at the SBMM cleanup site. A total of 23 samples were collected: 15 samples were collected by USGS from various waste piles during 2020-21 (14...
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California Water Science Center

Water quality, nutrient, and phytoplankton data from Franks Tract, Mildred Island, and neighboring channels in the California Sacramento-San Joaquin Delta: 2022 and 2023 High-resolution mapping surveys Water quality, nutrient, and phytoplankton data from Franks Tract, Mildred Island, and neighboring channels in the California Sacramento-San Joaquin Delta: 2022 and 2023 High-resolution mapping surveys

Surface water quality, water isotope, and phytoplankton enumeration data were collected to evaluate the impact of an Emergency Drought Barrier (EDB) in False River in the Sacramento-San Joaquin Delta. Data were collected on six days during 2022 and 2023 (June 7, June 21, July 27, August 9, October 12, November 30, 2022, and February 21, 2023). Sampling occurred in Franks Tract, Mildred...
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California Water Science Center
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