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Methods for computing water-quality loads at sites in the U.S. Geological Survey National Water Quality Network

January 1, 2017

The U.S. Geological Survey currently (2020) publishes information on concentrations and loads of water-quality constituents at 110 sites across the United States as part of the U.S. Geological Survey National Water Quality Network (NWQN). This report details historical and updated methods for computing water-quality loads at NWQN sites. The primary updates to historical load estimation methods include (1) an adaptation to methods for computing loads to the Gulf of Mexico; (2) the inclusion of loads and trends computed using the Weighted Regressions on Time, Discharge, and Season (WRTDS) and Weighted Regressions on Time, Discharge, and Season with Kalman filtering (WRTDS–K) methods; and (3) the inclusion of loads computed using continuous water-quality data. Loads computed using WRTDS and WRTDS–K and continuous water-quality data are provided along with those computed using historical methods. Various aspects of method updates are evaluated in this report to help users of water-quality loading data determine which estimation methods best suit their particular application.

Publication Year 2017
Title Methods for computing water-quality loads at sites in the U.S. Geological Survey National Water Quality Network
DOI 10.3133/ofr20171120
Authors Casey J. Lee, Jennifer C. Murphy, Charles G. Crawford, Jeffrey R. Deacon
Publication Type Report
Publication Subtype USGS Numbered Series
Series Title Open-File Report
Series Number 2017-1120
Index ID ofr20171120
Record Source USGS Publications Warehouse
USGS Organization Kansas Water Science Center