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Point-Source Nutrient Loads to Streams of the Conterminous United States, 2012

Metadata Updated: October 29, 2023

The U.S. Geological Survey (USGS) developed a spatial water-quality model called SPAtially Referenced Regressions On Watershed attributes (SPARROW) to estimate the major sources and environmental factors that affect the long-term supply, transport, and fate of contaminants in the Nation’s streams. The SPARROW model relates in-stream water-quality data to spatially referenced characteristics of watersheds, including contaminant sources and factors influencing terrestrial and aquatic transport. Based on SPARROW modeling, one of the main nutrient sources to streams is point-source facilities such as municipal waste-water treatment plants that discharge directly to streams. This dataset was developed to assist with SPARROW models developed to assess supply, transport and fate of total nitrogen and phosphorous in streams of the conterminous United States (2012). This dataset documents discharge information from point sources in the conterminous United States and was obtained from the EPA Integrated Compliance Information System (ICIS) and Permit Compliance System (PCS). When available, nutrient concentrations were used to calculate point source loads. However, in many cases measured concentration data were not available in the ICIS or PCS data base and so “typical pollutant concentrations” (TPC’s) were developed using data from similar facilities. A new method for calculating TPC’s was implemented that allows varying amounts of nutrient concentration data and/or varying numbers of facilities to determine TPC’s. This dataset contains the EPA facility, flow, and concentration data and all updates to the data, along with the TPC tables and resultant total nitrogen and phosphorous loads calculated from the input datasets.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

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Metadata Created Date June 1, 2023
Metadata Updated Date October 29, 2023

Metadata Source

Harvested from DOI EDI

Additional Metadata

Resource Type Dataset
Metadata Created Date June 1, 2023
Metadata Updated Date October 29, 2023
Publisher U.S. Geological Survey
Identifier USGS:5ba54362e4b08583a5c9d4e5
Data Last Modified 20200820
Category geospatial
Public Access Level public
Bureau Code 010:12
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id 205216a2-4df6-4058-b289-f20c759e6f16
Harvest Source Id 52bfcc16-6e15-478f-809a-b1bc76f1aeda
Harvest Source Title DOI EDI
Metadata Type geospatial
Old Spatial -124.6625,25.7456,-66.982966624,48.977133183
Publisher Hierarchy White House > U.S. Department of the Interior > U.S. Geological Survey
Source Datajson Identifier True
Source Hash 3d387d2fd35542b725259e72f79a394d25b9ad0a59253c0966df3ca974eddbb8
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -124.6625, 25.7456, -124.6625, 48.977133183, -66.982966624, 48.977133183, -66.982966624, 25.7456, -124.6625, 25.7456}

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