Data

The U.S. Geological Survey (USGS) derived soil-water distribution coefficients (Kd values) from per- and polyfluoroalkyl substances (PFAS) analytical chemistry data and soil properties based on soil and groundwater samples collected by the Maine Department of Environmental Protection between 2019 and 2024. Samples were collected at agricultural biosolid application sites in Maine. At...

In 2016, the United States Geological Survey (USGS) began development of a regional-scale numerical model of the Long Island aquifer system, as part of the National Water Quality Assessment (NAWQA) Program. The three-dimensional groundwater-flow model was developed to evaluate 1) responses of the hydrologic system to changes in natural and anthropogenic hydraulic stresses 2) the...

The U.S. Geological Survey, in cooperation with the Air Force Civil Engineer Center, developed a numerical, steady-state regional model, using MODFLOW-2005, to evaluate current (2010) conditions and the potential effects of future (2030) groundwater withdrawals on water levels, stream flows, hydraulic gradients, and advective transport near the Joint Base Cape Cod (JBCC). Two numerical...

We computed mean groundwater ages and age distributions at eight wells by calibrating lumped parameter models (LPMs) to concentrations of tracers (3H, CFCs, SF6) in samples using the computer program TracerLPM (Jurgens and others, 2012). We also measured 14C but all samples contained ancient carbonate from the limestone bedrock, and we were unable to resolve the atmospherically-derived...

The dataset presents 5- or 15-minute data for turbidity and Fluorescent Dissolved Organic Matter (FDOM) measured by in-stream sensors at the USGS gage Rio Icacos near Naguabo (50075000), Luquillo Experimental Forest, Puerto Rico. The measurement period was 10 March, 2017 to 1 March, 2019. The USGS sensors were co-located with sensors for nitrate and specific conductance operated by...

This data release supports publications on the Sleepers River Research Watershed near Danville, Vermont. Most of the research at Sleepers River takes place at W-9, the 40.5-hectare forested headwater site. Topics include understanding hydrologic flow paths, biogeochemical cycling, and organic carbon dynamics. Flow and precipitation data are integral to understanding these processes, for...

This data release presents water-quality and streamflow data from 12 streams on Cape Cod, Massachusetts, which were used to identify potential land areas that are sources of high nitrogen loading from groundwater directly to streams. The sources of nitrogen loading to groundwater in this region include wastewater from septic systems and fertilizer and stormwater runoff. Streamflow in the...

This dataset provides details from stream metabolism models for 11 stream sites in Connecticut that were monitored during 2015 to 2018 by the U.S. Geological Survey (USGS). Metabolism was estimated at each site using the streamMetabolizer package in the R computing environment. When data were collected for multiple years at a site, stream metabolism was separately estimated for each year...

This data release documents nitrate-nitrogen concentration, groundwater ages, age-weighted nitrogen loads, and aquifer and other characteristics that could be used to model time-varying nitrate concentration in groundwater on Long Island, New York. Concentration data consist of median annual nitrate concentrations at approximately 700 supply wells from 1988 to 2019 based on data provided...

The U.S. Geological Survey (USGS), in cooperation with the Vermont Agency of Transportation (VTrans), derived watershed boundaries for the State of Vermont at the 1-meter resolution using lidar Digital Elevation Models (DEMs). Geographic Information Systems (GIS) software was used to hydrologically enforce DEMs and delineate watershed boundaries at 402 selected ungaged pour point...

From October 2022 through September 2024, the U.S. Geological Survey (USGS) National Water Quality Network (NWQN) monitored 110 surface-water river and stream sites and about 700 groundwater wells for a large number of water-quality analytes, for which associated quality-control data and corresponding statistical summaries are included in this data release. The quality-control data—for...

This data release contains the Land Use/Land Cover (LULC) data available in the Neponset River Basin StreamStats application. The U.S. Environmental Protection Agency (EPA) used the hydrologic response unit (HRU) approach outlined in EPA (2023) to derive the LULC raster from Massachusetts 2016 LULC data from MassGIS (2019), and the Natural Resources Conservation Service Soil Survey...