Downspouts
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Background
Typically, rain falls on a roof, flows through downspouts and over impervious surfaces, then travels into off-site stormwater treatment systems. The diversion of downspouts to pervious areas creates the following improvements:
- Water that would be wasted as runoff is used to meet plant water needs.
- Water that would typically run off and burden the stormwater system infiltrates the soil and is treated on-site.
Requirements and certification
Downspouts shall be directed to pervious areas onsite two feet or more from foundation.
Silver | Gold | Commercial/Institutional |
NA | 15 | NA |
Program tip
The inspector must visually confirm presence of gutters, partial or complete. Downspout extenders may be used to achieve credit.