Planning for Stormwater: Parking Lots

Storrs, CT (2002)- Paved parking lots are typically designed to collect and concentrate large areas of stormwater runoff, which can impact a receiving stream’s hydrography as well as water quality. Paved parking lots can generate heat, raising the surrounding areas air temperature and the temperature of the first flush of stormwater, creating significant ecological impacts.


In Washington, the City of Olympia’s Public Works Department found that parking lots account for 53% of imperviousness on a commercial site and 15% of multi-family sites. These figures are typical of most communities. Therefore, careful attention to their design will go a long way toward protecting your community’s water resources.
The University of Connecticut’s Planning for Stormwater website includes an overview of paved parking areas and their impact on stormwater runoff. This NEMO (Nonpoint Education for Municipal Officials) website focuses on the site planning concepts presented in Connecticut’s Stormwater Quality Manual.
For more information, visit the UConn Stormwater Nonpoint Education for Municipal Officials.
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