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New Additions to EPA’s Stormwater Calculator


The U.S. Environmental Protection Agency (EPA) just released phase II of its of the National Stormwater Calculator and Climate Assessment Tool package. This desktop application can be used to estimate the annual amount of rainwater and frequency of runoff from a specific location anywhere in the United States, including Puerto Rico. It measures soil conditions, slope, land cover, and historical rainfall records.

The Calculator now includes changes in seasonal precipitation levels, the effects of more frequent high-intensity storms, and changes in evaporation rates.

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 stormwater runoff. With this information, users can learn how adding green infrastructure can be one of the most cost-effective ways to reduce stormwater runoff.

Read EPA’s full press release.

Find more information on the stormwater calculator.