Skip to main content
U.S. flag

An official website of the United States government

Point-Source Load Estimation Tool (PSLoadEsT)

April 4, 2019

The Point-Source Load Estimation Tool (PSLoadEsT) was developed as a user-friendly method for estimating annual wastewater nutrient loads while managing the challenges of missing, duplicated, or erroneous nutrient concentration and effluent flow data for the purposes of model calibration and application. PSLoadEsT is written in the R programing language (R Core Team, 2016) with a push-button Microsoft Access® interface scripted in Visual Basic for Applications®. The tool is primarily based on the methods outlined in “Methods for Estimating Annual Wastewater Nutrient Loads in the Southeastern United States” (McMahon and others, 2007), and program steps and objectnames follow these methods closely.

User Guide:

Gorman Sanisaca, L.E., Skinner, K.D., and Maupin, M.A., 2019, Annual wastewater nutrient data preparation and load estimation using the Point Source Load Estimation Tool (PSLoadEsT): U.S. Geological Survey Open-File Report 2019-1025, 48 p., https://doi.org/10.3133/ofr20191025