EPA Updates National Stormwater Calculator

Jan. 31, 2014
The updated calculator includes future climate vulnerability scenarios

The U.S. Environmental Protection Agency (EPA) released phase II of the National Stormwater Calculator and Climate Assessment Tool package. The updated calculator includes future climate vulnerability scenarios.

The calculator, a part of President Obama’s Climate Change Action Plan, is a desktop application that estimates the annual amount of storm water runoff from a specific location. The calculator now includes changes in seasonal precipitation levels, the effects of more frequent high-intensity storms and changes in evaporation rates based on validated climate change scenarios by the Intergovernmental Panel on Climate Change.

The updated calculator includes climate models that can be incorporated into the calculation of storm water runoff. This adds future climate scenarios to last year’s phase I release, which included local soil conditions, slope, land cover, historical rainfall records.

Users can enter any U.S. location and select different scenarios to learn how specific green infrastructure changes, including inexpensive changes such as rain barrels and rain gardens, can reduce storm water runoff. This information shows users how adding green infrastructure, which mimics natural processes, can be one of the most cost-effective ways to reduce storm water runoff.

Every year billions of gallons of raw sewage, trash, household chemicals, and urban runoff flow into our streams, rivers and lakes. Polluted storm water runoff can adversely affect plants, animals, and people. It also negatively impacts the economy—from closed beaches to decreased fishing in polluted areas. Green infrastructure can reduce the damage caused by climate change by improving water quality in streams and rivers, protecting groundwater sources, and enhancing recreational activities. Using the calculator to choose the best green infrastructure options for an area is an innovative and efficient way to promote healthy waters and support sustainable communities.

Source: EPA