Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Skip to content

SPARROW model datasets for total nitrogen and total phosphorus in North Carolina, including simulated stream loads

Metadata Updated: October 29, 2023

To better understand the influence of human activities and natural processes on surface-water quality, the U.S. Geological Survey (USGS) developed the SPARROW (SPAtially Referenced Regressions On Watershed attributes) (Schwarz and others, 2006; Alexander and others, 2008) model. The framework is used to relate water-quality monitoring data to sources and watershed characteristics that affect the fate and transport of constituents to receiving surface-water bodies. The core of the model consists of using a nonlinear-regression equation to describe the non-conservative transport of contaminants from point and nonpoint sources on land to rivers, lakes and estuaries through the stream and river network. In North Carolina, excessive sediment loadings have contributed to the degradation of surface-water quality, and point and nonpoint nutrient sources are recognized as major contributors of this degradation in rivers, lakes and estuaries. The SPARROW model was configured for North Carolina to predict total nitrogen and total phosphorus loads in streams and to evaluate the relative importance and contributions of nitrogen and phosphorus sources and other landscape characteristics. The model time period is 1999 to 2014, centered at 2012. This data release includes model input (, model predictions ( and that represent simulated stream load, model catchment shapefile (, and a brief methodology (Methodology_TNTP.pdf). See the 'Methodology_TNTP.pdf' file for model documentation.

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.

Downloads & Resources


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:5bb4dd11e4b08583a5da3a8b
Data Last Modified 20200827
Category geospatial
Public Access Level public
Bureau Code 010:12
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id e90bbbd2-4840-49f3-a9d8-54ec91ebbc23
Harvest Source Id 52bfcc16-6e15-478f-809a-b1bc76f1aeda
Harvest Source Title DOI EDI
Metadata Type geospatial
Old Spatial -84.418945312729,33.760518252617,-75.278320313094,36.773742030525
Publisher Hierarchy White House > U.S. Department of the Interior > U.S. Geological Survey
Source Datajson Identifier True
Source Hash 8665c52944de589f94b5b174fbc3383732ceb485630b3864f5214fdacab4681e
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -84.418945312729, 33.760518252617, -84.418945312729, 36.773742030525, -75.278320313094, 36.773742030525, -75.278320313094, 33.760518252617, -84.418945312729, 33.760518252617}

Didn't find what you're looking for? Suggest a dataset here.