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Water-quality and streamflow datasets used in Weighted Regressions on Time, Discharge, and Season (WRTDS) models to determine trends in the Nation’s rivers and streams, 1972-2017 (output data)

Metadata Updated: July 6, 2024

In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project. One of the major goals of the NAWQA project was to determine how river water quality has changed over time. To support that goal, long-term consistent and comparable monitoring has been conducted by the USGS on streams and rivers throughout the Nation. Outside of the NAWQA project, the USGS and other Federal, State, and local agencies also have collected long-term water-quality data to support their own assessments of changing water quality. In 2017, data from these multiple sources were combined to support one of the most comprehensive assessments to date of water-quality trends in the United States (Oelsner and others, 2017; De Cicco and others, 2017). This data release updates these water quality trends, which ended in 2012, with 5 more years of data and now end in 2017. These datasets contain the output from the WRTDS trend models that characterize changes in water quality in rivers and streams across the Nation. The "compiledResults_final" folder contains 3 output tables: "allAnnualResults.csv", "bootOut.csv", and "parisOut.csv". "allAnnualResults.csv" contains several types of estimates of annual mean concentration and fluxes for the entire calibration period for each combination of site and parameter. These estimates include "true condition" estimates determined using the original implementation of WRTDS ("_orig" suffix). "true condition" estimates determined using WRTDS_K (i.e. using a Kalman filter: "_K" suffix), flow normalized (FN) trend estimates ("FN prefix"), lower and upper 90% confidence intervals of FN trend estimates ("FN" prefix with "Low" or "High" suffix), and FN trend estimates assuming a stationary flow regime ("SFN" suffix). Water quality changes were calculated for up to six trend periods (1972-2017, 1982-2017, 1992-2017, 2002-2017, and 2007-2017) per site and parameter. "bootOut.csv" gives the results of the bootstrap trend test, including uncertainty estimates, by site parameter and trend period. "pairsOut.csv" gives the trend component estimates (concentration-discharge trend component (CQCT), also referred to as the "management" trend component (MTC)) and discharge trend component (QTC) and related information, by site, parameter, trend period, and estimate type (i.e. concentration or flux). Finally, the "eList" for each WRTDS model (site-parameter combination) is available in the zipped folder according to whether the model was accepted or rejected; "" and "", respectively. The output tables in "" contain results only for models that had acceptable fits, as determined by an estimated probability of acceptance or by manual evaluation of residual and diagnostic plots. eLists are compiled according to whether the model was accepted or rejected.

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 July 6, 2024

Metadata Source

Harvested from DOI EDI

Additional Metadata

Resource Type Dataset
Metadata Created Date June 1, 2023
Metadata Updated Date July 6, 2024
Publisher U.S. Geological Survey
Identifier USGS:60e61aafd34e2a7685cf637b
Data Last Modified 20221123
Category geospatial
Public Access Level public
Bureau Code 010:12
Metadata Context
Metadata Catalog ID
Schema Version
Catalog Describedby
Harvest Object Id 87bdd908-fb36-4d62-b30e-7e31c656b1e7
Harvest Source Id 52bfcc16-6e15-478f-809a-b1bc76f1aeda
Harvest Source Title DOI EDI
Metadata Type geospatial
Old Spatial -125.5078,17.3087,-64.5117,48.9225
Publisher Hierarchy White House > U.S. Department of the Interior > U.S. Geological Survey
Source Datajson Identifier True
Source Hash 06b7193fc6138c8336d4ab788c2966154b501e186c346b2321ab0713c6ada572
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -125.5078, 17.3087, -125.5078, 48.9225, -64.5117, 48.9225, -64.5117, 17.3087, -125.5078, 17.3087}

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