Data

Edwards Air Force Base (EAFB) is located about eight kilometers (km) northeast of the city of Lancaster, California. In 1990 EAFB was placed on the U.S. Environmental Protection Agency's National priorities list due to the presence of contaminated soil and groundwater. The base was divided into Operable Units (OU) based on location and similar contaminant types (Lahontan Staff Report, 2010). The A

To better understand the potential pesticide exposure, samples were collected from locations along two creeks in Pinnacles National Park and four creeks in nearby Bureau of Land Management (BLM) lands. Silicone bands were used as passive sampling devices (PSD) staked in the creek and above in the air (above the water line). Sampling was conducted in the summer from 2019 to 2021. PSDs were deployed

Zooplankton samples were collected at a site in the Yolo Bypass in Northern California 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 biweekly in the summer/fall 2017 and 2018, and from May 2019-March 2020. Samples were collected by towing a 150-micron conical plankton net

The U.S. Geological Survey collected groundwater samples from 71 wells used for domestic and small system drinking water supplies in Stanislaus and Merced counties of California during 2020-2021. The wells were sampled for the Modesto-Turlock-Merced Domestic-Supply Aquifer Study Unit of the State Water Resources Control Board Groundwater Ambient Monitoring and Assessment (GAMA) Program Priority Ba

Seven model data sets are archived for this groundwater study. One simulation for the Los Angeles Coastal Plain groundwater model and six scenario simulations to evaluate the effects of future production well rate increases to reach maximum adjudicated rates and construction of new well fields. Simulations were run with MODFLOW-USG.

The U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (Water Board) collected produced water and casing gas samples from petroleum wells and other oil-field sites in selected oil fields in the southern San Joaquin Valley in Kern County in 2016 and 2017. The samples were collected as part of the Water Boards Regional Groundwater Monitoring Program

Due to declining water levels and increasing salinity in the Salton Sea which may increase the hazards to wildlife, the U.S. Geological Survey and U.S. Bureau of Reclamation are re-evaluating selenium concentrations in the region. As part of this work, selenium concentrations in water and sediment samples and selected other inorganic constituents were compiled from published reports, public databa

The Petaluma Valley integrated hydrologic model (PVIHM) was developed by the U.S. Geological Survey (USGS) in cooperation with the Sonoma County Water Agency and the City of Petaluma. The PVIHM simulates the 99,000-acre Petaluma valley watershed and includes 54,000 acres where groundwater flow is active. The model simulates 56 years of historical hydrology (water years 1960–2015) that includes a r

This data release contains digital data generated by the U.S. Geological Survey under cooperative agreements with San Bernardino Valley Municipal Water District to characterize the three-dimensional hydrogeology of the Yucaipa groundwater subbasin, located east of Los Angeles in southern California. This dataset contains borehole lithologic data, and geospatial data of a three-dimensional hydrogeo

The San Antonio Creek Valley watershed (SACVW) is located in western Santa Barbara County about 15 miles (mi) south of Santa Maria, California and 55 mi north of Santa Barbara, California. The SACVW, is about 140 square miles and encompasses the San Antonio Creek Valley groundwater basin. Since the late 1800s, groundwater has been the primary source of water for agricultural, military, municipal,

To better understand the exposure of wild bees to pesticides in an agricultural landscape, samples were collected from fields in northern California. Hedgerows are known to provide habitat for wild bees, but these bees may also be exposed to pesticides from nearby agricultural fields. The study included eight hedgerow sites located in an intensively managed agricultural landscape that includes alm

Model archive summary (MAS) describing the development of a suspended-sediment concentration (SSC) surrogate regression model for the Mad River Slough near Arcata, CA water quality station (USGS site ID# 405219124085601). A 15-minute SSC record was computed using this regression model for the period of record (03-04-2016 to 09-10-2019). The computed SSC record can be found on NWIS Web at https://w