Reports

Executive Summary The purpose of this report is to provide the Marine Corps with an annual summary of the distribution, abundance, and breeding activity of the endangered Southwestern Willow Flycatcher (Empidonax traillii extimus; flycatcher) and to present results of management actions implemented to attract flycatchers and enhance flycatcher habitat at Marine Corps Base Camp Pendleton...

The U.S. Army Corps of Engineers, Jacksonville District, deepened the St. Johns River channel in Jacksonville, Florida, to accommodate larger, fully loaded cargo vessels. The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, monitored stage, discharge, and (or) water temperature and salinity at 26 continuous data collection sites in the St. Johns River...

Historical, future, and potential stream capture from groundwater pumping in the middle Humboldt River Basin (MHRB), Nevada, is estimated using a calibrated numerical groundwater flow model. The model was developed to estimate (1) stream capture, which is the change in flux between the groundwater system and the Humboldt River and tributaries, and (2) change in streamflow, which is the...

This report provides actionable guidance for scientists developing scientific tools that inform on-the-ground decision making. Scientific tools, in the context of this report, are technology or protocols that help practitioners collect and analyze their own data, and information products and web tools that practitioners could use to inform decisions. Engaging end-users and fellow experts...

The area surrounding the Salinas Valley groundwater basin in Monterey and San Luis Obispo Counties of California is a highly productive agricultural area, contributes substantially to the local economy, and provides a substantial portion of vegetables and other agricultural commodities to the Nation. This region of California provides about half of the Nation’s lettuce, celery, broccoli...

The City of Sioux Falls, South Dakota, requested the U.S. Geological Survey perform electrical resistivity surveys on three parcels of land north of the city. Electrical resistivity data were collected along a total of 22 transects during March 14–18, 2022, and November 17–21, 2025. Results from electrical resistivity surveys were used to delineate the top of glacial till deposits for...

This study was conducted by the U.S. Geological Survey, in cooperation with the Oklahoma Water Resources Board, to update the hydrogeologic framework and conceptual flow model for the panhandle and northwest parts of the High Plains (Ogallala) aquifer in Oklahoma, which together compose the Ogallala aquifer focus area. The study included the construction of a potentiometric surface, and...

Per- and polyfluoroalkyl substances (PFAS), including perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), have been detected at combined concentrations above 2,000 nanograms per liter (ng/L) at groundwater seep locations near the Coakley Landfill Superfund site, in North Hampton, New Hampshire. The landfill was active from 1972 to 1985. An impermeable cap was placed on...

No abstract available.

The U.S. Geological Survey, in cooperation with Idaho Power, developed streamflow- based regression models to estimate suspended sediment concentration (SSC) and loads on the Snake River at Weiser, Idaho site (U.S. Geological Survey streamgage 13269000; hereafter referred to as “Snake at Weiser site”). This site sits upstream from the dams and reservoirs of the Hells Canyon Complex and...

Introduction In September 2021, National Park Service staff, U.S. Geological Survey scientists, and an international team of researchers revealed evidence in the form of human footprints at White Sands National Park, New Mexico, that showed people were present in North America between 23,000 and 21,000 years ago. This time was during the Last Glacial Maximum, when large ice sheets...

The U.S. Geological Survey (USGS), in cooperation with the Louisiana Department of Transportation and Development, collected water-withdrawal and water-use data from a 2020 inventory of water withdrawals in Louisiana. In 2020, approximately 8,700 million gallons per day (Mgal/d) of water was withdrawn from groundwater and surface-water sources in Louisiana, which represented a 0.22...