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National Stormwater Calculator (Fact Sheet)

This fact sheets provides information on EPA's National Stormwater Calculator (SWC). The SWC was developed to help support local, state, and national stormwater management objectives and regulatory efforts to reduce runoff through infiltration and retention using green infrastructure practices as low impact development (LID) controls. The primary focus of the SWC is to inform site developers on how well they can meet a desired stormwater retention target with and without the use of green infrastructure. It can also be used by landscapers and homeowners. 

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