Skip to main content
Advanced Search

Filters: Tags: National Water Quality Program (X) > partyWithName: Water Resources (X) > Types: OGC WMS Service (X) > Types: Citation (X)

5 results (7ms)   

View Results as: JSON ATOM CSV
thumbnail
Ecological assessment data from the USGS National Water-Quality Assessment Program and the USEPA National River and Stream Assessment were reviewed and records were retained from sampling sites co-located with active USGS stream gages. A limited amount of ancillary data, including location, physical watershed features, and basic water chemistry data for each site were also retained.
thumbnail
This dataset is comprised of water quality data and benthic macroinvertebrate data collected from basins in Colorado, USA, and Finland. The data includes ancillary water quality characteristics but also a suite of trace metals observed at each site. Also included are modeled outputs that characterize the bioavailability of each trace metal to a biotic ligand. These data were used to explore the importance of metal toxicity and pH as stressors on benthic macroinvertebrates characterized as the number of unique Ephemeroptera + Plecoptera + Trichoptera genera observed at each site. An interpretive summary of the work follows. One of the primary goals of biological assessment of rivers is to identify whether contaminants...
thumbnail
Groundwater-quality data were collected from 559 wells as part of the National Water-Quality Assessment Project of the U.S. Geological Survey National Water-Quality Program from January through December 2014. The data were collected from four types of well networks: principal aquifer study networks, which assess the quality of groundwater used for public water supply; land-use study networks, which assess land-use effects on shallow groundwater quality; major aquifer study networks, which assess the quality of groundwater used for domestic supply; and enhanced trends networks, which evaluate the time scales during which groundwater quality changes. Groundwater samples were analyzed for a large number of water-quality...
thumbnail
Widespread nitrate contamination of groundwater in agricultural areas poses a major challenge to sustainable water resources. Efficient analysis of nitrate fluxes across large regions also remains difficult. This study introduces a method of characterizing nitrate transport processes continuously across regional unsaturated zones and groundwater based on surrogate, machine-learning metamodels of an N flux process-based model. The metamodels used boosted regression trees (BRTs) to relate mappable variables to parameters and outputs of a “vertical flux method” (VFM) applied in the Fox-Wolf-Peshtigo (FWP) area in Wisconsin. In this context, the metamodels are upscaling the VFM results throughout the region, and the...
thumbnail
The ascii grids represent regional probabilities that groundwater in a particular location will have dissolved oxygen (DO) concentrations less than selected threshold values representing anoxic groundwater conditions or will have dissolved manganese (Mn) concentrations greater than selected threshold values representing secondary drinking water-quality contaminant levels (SMCL) and health-based screening levels (HBSL) for water quality. The probability models were constrained by the alluvial boundary of the Central Valley to a depth of approximately 300 meters (m). We utilized prediction modeling methods, specifically boosted regression trees (BRT) with a Bernoulli error distribution within a statistical learning...
    map background search result map search result map Probability distribution grids of dissolved oxygen and dissolved manganese concentrations at selected thresholds in drinking water depth zones, Central Valley, California Datasets from Groundwater-Quality Data from the National Water-Quality Assessment Project, January through December 2014 and Select Quality-Control Data from May 2012 through December 2014 Disentangling the effects of low pH and metal mixture toxicity on macroinvertebrate diversity: data sets Matched ecological assessment and stream gaging data for the CONUS Data Release for Metamodeling and Mapping of Nitrate Flux in the Unsaturated Zone and Groundwater, Wisconsin, USA Data Release for Metamodeling and Mapping of Nitrate Flux in the Unsaturated Zone and Groundwater, Wisconsin, USA Probability distribution grids of dissolved oxygen and dissolved manganese concentrations at selected thresholds in drinking water depth zones, Central Valley, California Matched ecological assessment and stream gaging data for the CONUS Datasets from Groundwater-Quality Data from the National Water-Quality Assessment Project, January through December 2014 and Select Quality-Control Data from May 2012 through December 2014 Disentangling the effects of low pH and metal mixture toxicity on macroinvertebrate diversity: data sets