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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.

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Water Quality Samples for USGS 11092450 LOS ANGELES R A SEPULVEDA DAM CA

Water-quality data collected for various parameters at USGS monitoring site 11092450 (Los Angeles River at Sepulveda Dam).

Basin Characterization Model (BCMv8) monthly recharge and runoff for the Anza-Cahuilla Groundwater Basin, California

This dataset provides monthly and average annual long-term estimates (water years 1981-2010) of gridded recharge and runoff from water years 1896-2018 for the Anza-Cahuilla Groundwater Basin in southern California. Gridded data are available in flat ASCII files (*.asc) in the NAD83 California Teale Albers projection. This dataset also includes streamflow calibration basins and stations as shape fi

Data sets for: Sampling for Per- and Polyfluoroalkyl Substances (PFAS) by the Groundwater Ambient Monitoring and Assessment Priority Basin Project (GAMA-PBP)

The U.S. Geological Survey Groundwater Ambient Monitoring and Assessment-Priority Basin Project (USGS GAMA-PBP) collected samples to be analyzed for per-and polyfluoroalkyl substances (PFAS) from domestic and public supply wells from May 2019 to September 2020. The datasets presented here include identification of the 28 PFAS constituents monitored by the project, Identification and brief characte

Historical groundwater and produced water chemistry data compiled for the San Ardo Oil Field and vicinity, Monterey County, central California

This digital dataset includes 255 samples from 41 groundwater wells and 271 samples of produced water from 143 sites (including 101 wells) located within 3 miles of the San Ardo Oil Field in Monterey County, central California. Historical geochemistry data were compiled from multiple data sources for selected water-quality indicators, major and minor ions, nutrients, and trace elements. Ancillary

Pesticide detections in streams throughout the foothills of the Sierra Nevada range using passive samplers from 2017 to 2019

This dataset was produced from analyzing Affinisep SDB-RPS, Affinisep HLB, and Restek Resprep C18 disks that were deployed with the use of Chemcatcher� passive sampling devices. Silicone bands were also deployed and used for exploring economical methods of sampling for pesticides in surface water. Sampling assemblies were deployed in streams throughout the foothills of the Sierra Nevada range and

Mud logs from the Oxnard Oil Field, Ventura County, California

The U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB) compiled and digitized mud logs from oil and gas wells in the Oxnard Oil Field area. Scanned copies of the mud logs were downloaded from the California Geologic Energy Management Division (CalGEM) online data and were digitized. Thirteen available mud logs associated with the Pliocene T

Fluid levels in the Oxnard Oil Field, Ventura County, California

The U.S. Geological Survey (USGS), in cooperation with the California State Water Resources Control Board (SWRCB), compiled Fall 2017 fluid level elevation data from idle oil and gas wells in the Oxnard Oil Field to estimate vertical hydraulic head difference between oil production and overlying groundwater aquifer zones. Fluid elevations came from two sources, measurements in idle oil and gas wel

Vertical Distribution of Longfin Smelt in the San Francisco Estuary (ver. 2.1, August 2020)

Field data for fishes sampled using mid-water trawls, otter trawls, and the SmeltCam during day and night in San Pablo Bay, CA. This data release includes all measured environmental parameters and fish taxa included in the analysis.

Erodibility Data from Gust Erosion Chamber Experiments in Grizzly Bay and San Pablo Bay, California, Summer 2019

A Gust erosion chamber was used to apply horizontal shear stress to sediment cores obtained from San Pablo and Grizzly (within Suisun) Bays in California. A pair of sediment cores were collected from the same approximate locations in each bay six times between June 12th, 2019 and August 15th, 2019 for a total of 12 experiments and 24 sediment core results. Locations were chosen to capture the bent

Verified Irrigated Agricultural Lands for the United States, 2002-17

The spatial extents of verified irrigated lands were compiled from various federal and state sources across the nation and combined into a single Geographic Information System (GIS) geodatabase for the purpose of model training and validation. In cooperation with U.S. Geological Survey (USGS), researchers at the University of Wisconsin (UW) generated a nation-wide map of irrigated lands using remo

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, untreated seed,

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 oxygen, and chl