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Pollution Calculators

One of the best ways to ensure that communities are using the most effective combination of watershed management practices is through the evaluation of costs and pollution removal effectiveness. The Watershed Treatment Model and the Clean Water Optimization Tool are two tools developed by the Center that estimate pollution loads and reductions at the watershed or jurisdiction scale. These two spreadsheets allow a variety of customization by users and can be used alone and in combination depending on the information available and output desired. Both spreadsheets are free and downloadable from our site.

The Watershed Treatment Model (WTM) 2013 is a spreadsheet-based model that helps users calculate annual pollutant loads and runoff volumes and estimate benefits from a wide range of stormwater runoff and pollutant removal practices. There are two versions: an ”off-the-shelf” version that comes as-is and has a simple user interface, and a customizable version. Free downloads of the WTM and associated resources are provided below and can also be found in our Online Watershed Library (OWL) http://owl.cwp.org/mdocs-posts/watershed-treatment-model-wtm-2013/. To provide feedback, ask questions or report problems with the Tool, contact Deb Caraco at dsc@cwp.org.

The Clean Water Optimization Tool is a planning tool for Maryland communities to develop more cost-effective strategies for reducing stormwater pollution to meet nutrient and sediment reduction goals. Although the impetus for the Tool was the Chesapeake Bay TMDL, it can also be used to address local impairments for nutrients and sediment. The Tool was developed by the Center for Watershed Protection with funding from the Town Creek Foundation and it allows the user to optimize BMP selection based on cost-effectiveness for a particular pollutant, determine the practical limits of implementation, and evaluate progress towards water quality goals. The Tool also includes the most up-to-date crediting procedures approved by the Chesapeake Bay Program and allows the user to evaluate the impact of practices that have not yet been approved. Free downloads of the Tool and associated resources are provided below and can also be found in our Online Watershed Library (OWL). To provide feedback, ask questions or report problems with the Tool, contact Reid Christianson at rdc@cwp.org.

Both the Watershed Treatment Model and the Clean Water Optimization Tool are owned by the Center for Watershed Protection and were developed for educational, research, and non-profit purposes. Use of these tools, their components or derivations for profit is strictly prohibited.