Data

California's Central Valley ranges from the mountain fronts toward a central trough, mainly defined by the San Joaquin and Sacramento Rivers, and the relative distance from trough to valley edges is of interest. This data release provides supplemental data for the USGS Professional Paper 1766, titled Groundwater Availability of the Central Valley Aquifer, California and provides geographic informa

An extreme gradient boosting (XGB) machine learning model was developed to predict the distribution of nitrate in shallow groundwater across the conterminous United States (CONUS). Nitrate was predicted at a 1-square-kilometer (km) resolution at a depth below the water table of 10 m. The model builds off a previous XGB machine learning model developed to predict nitrate at domestic and public supp

Data provided here describe the contribution of up to 7 different water sources to the major ion geochemistry of U.S. Geological Survey (USGS) and California State Water Resources Control Board Division of Drinking Water (CA-DDW) groundwater samples within the Indio Subbasin of the Coachella Valley, California. The Inverse Geochemical Modeling was performed in the USGS's PHREEQC ver. 3 program and

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 information about

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 pore water we

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 from Sacrame

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 towing a 1

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, hydrauli

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 from individ

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 about 255,000 well completion reports (WCRs) for water supply wells from Amador, Butte, Calaveras, Colusa, El Dorado, Glenn, Kern, Kings, Merced,

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 cooperation

This digital dataset contains the surface water operational data used for the Salinas Valley Operational Model (SVOM) including the time series data and the operational rules. While much of the input data is shared between the Salinas Valley Operational Model (SVOM) and the Salinas Valley Integrated Hydrologic Model (SVIHM), the SVOM has additional input data specific to the purpose and function o