Data

To support an investigation of the feasibility of measuring river bathymetry using remotely sensed data acquired from an unmanned aircraft system (UAS), several types of remotely sensed data and field measurements were collected from two cross-sections on the Blue River and two cross-sections on the Colorado River near Kremmling, Colorado, on October 17-18, 2018. This parent data release includes

Phytoplankton is an important and limiting food source in the Sacramento-San Joaquin Delta and San Francisco Bay; the decline of phytoplankton biomass is one possible factor in the pelagic organism decline and specifically in the decline of the protected delta smelt. The bivalves Corbicula fluminea and Potamocorbula amurensis (hereafter Corbicula and Potamocorbula, respectively) have been shown to

This data release contains annual peak-flow data through the 2013 water year, specification and output files from flood-frequency analysis of the annual peak-flow data in USGS PeakFQ software, a GIS shapefile of the basin polygons with attributes of site information, basin characteristics, results of flood-frequency analysis, and results of B-WLS/B-GLS analysis of skewness of the annual peak flows

The mission of the U.S. Geological Survey (USGS) involves providing reliable, impartial, and timely information that is needed to understand the Nation?s water resource. New techniques that aid in achieving this mission are important, especially those that allow USGS to do so more accurately or cost-effectively. To this end, a new method for selecting the optimum exposure time for velocity and dis

A boosted regression tree (BRT) model was developed to predict pH conditions in three-dimensions throughout the glacial aquifer system (GLAC) of the contiguous United States using pH measurements in samples from 18,258 wells and predictor variables that represent aspects of the hydrogeologic setting. Model results indicate that the carbonate content of soils and aquifer materials strongly controls

Lithium concentrations in untreated groundwater from 1,464 public-supply wells, 1,676 domestic-supply wells, and 1,560 monitoring wells distributed across 33 principal aquifers in the United States were evaluated for spatial variations and possible explanatory factors. For context, lithium concentrations are compared to a drinking-water only threshold (60 mg/L) and a Health-Based Screening Level (

This dataset includes data collected to validate a method of analysis for arsenic species As(III), As(V), dimethylarsinate (DMA), and monomethylarsonate (MMA) in surface water and groundwater samples. It also includes site information and water chemistry for samples used in the validation and used for other studies of arsenic species in groundwater. It includes speciation data measured at multipl

This groundwater-flow model archive contains heuristic model simulations evaluating the sustainability of groundwater withdrawals from public-water-supply wells on buried glacial aquifers. A total of 40 steady-state simulations and three transient simulations were run. The steady-state simulations were developed to assess the extent and connections between buried sand aquifers by varying three h

The U.S. Geological Survey is monitoring concentrations of metals and other trace elements in water, streambed sediment, and aquatic invertebrates at 6 locations in the middle and lower portions of the mainstem Klamath River from below J.C. Boyle dam in Oregon to near the mouth on the northwestern coast of California. Included are 3 tributary monitoring sites, one each on the Scott, Salmon, and Tr

This product provides tabular estimates of kilograms of nitrogen and phosphorus from a) fertilizer, and b) manure, for counties in the conterminous United States for the period 1950-2017. Data are generated for approximate five-year periods over the time, coinciding with U.S. Department of Agriculture Census of Agriculture census years. This data release also includes a model archive suitable for

Remotely sensed imagery is increasingly used by emergency managers to monitor and map the impact of flood events to support preparedness, response, and critical decision making throughout the flood event lifecycle. To reduce latency in delivery of imagery-derived information, ensure consistent and reliably derived map products, and facilitate processing of an increasing volume of remote sensing da

The distribution of permafrost in cold regions is subject to temporal and spatial changes influenced by climate, landscape disturbance, and ecosystem succession. Remote sensing from airborne and satellite platforms is increasing our understanding of landscape-scale permafrost distribution, but typically lacks the resolution to characterize finer-scale processes and phenomena, which are often bette