EPA Pollutant Load Estimation Tool

<p><strong>Open the Data Resource:</strong> <a target='_blank' href='https://www.epa.gov/nps/plet' rel='nofollow ugc noopener noreferrer'>https://www.epa.gov/nps/plet</a></p><p>The Pollutant Load Estimation Tool (PLET) is a planning level web-based model used to estimate long-term nutrient and sediment loads from different land uses and the load reductions resulting from the implementation of best management practices.&nbsp;</p><p>PLET provides a user-friendly web interface to create a customized model at the watershed, field , or site scale. For the HUC 12 watershed scale data inputs are auto populated by the input data server.</p><p>PLET considers urban, cropland, pastureland, feedlot, forest and user defined land uses. The nonpoint sources include cropland, pastureland, farm animals, feedlots, urban runoff, and failing septic systems. In addition to estimating annual load reductions as a result of BMP implementation, PLET estimates nutrient and sediment loads prevented as a result of forested land protection.</p><p>PLET employs simple algorithms to compute surface runoff, nutrient loads and sediment delivery based on various land uses and best management practices. The annual nutrient loading is calculated based on the runoff volume and the pollutant concentrations in surface runoff as influenced by factors such as the land use distribution and management practices. The annual sediment load from sheet and rill erosion is calculated based on the Revised Universal Soil Loss Equation Version 2 (RUSLE2) methodology and the sediment delivery ratio. &nbsp;</p><p>Input Data Server for PLET: The input data server provides initial model input data that can be used as a starting point in populating the PLET model. It provides information on land use acreages, agricultural animals, septic systems, and hydrological soil groups at the HUC12 scale. These data can be downloaded for use in other applications, or the data can be applied automatically to a PLET model as it is developed.&nbsp;</p>