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Gregory Hurst
Robert Peccia & Associates
Office Manager
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Credit language
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Requirements
Implement a stormwater management plan that reduces impervious cover, promotes infiltration and captures and treats the stormwater runoff from 90% of the average annual rainfall1 using acceptable best management practices (BMPs). BMPs used to treat runoff must be capable of removing 80% of the average annual postdevelopment total suspended solids (TSS) load based on existing monitoring reports. BMPs are considered to meet these criteria if:
- They are designed in accordance with standards and specifications from a state or local program that has adopted these performance standards.
- There exists infield performance monitoring data demonstrating compliance with the criteria. Data must conform to accepted protocol (e.g., Technology Acceptance Reciprocity Partnership [TARP], Washington State Department of Ecology) for BMP monitoring.
SITES-LEED Equivalency
This LEED credit (or a component of this credit) has been established as equivalent to a SITES v2 credit or component. For more information on using the equivalency as a substitution in your LEED or SITES project, see this article and guidance document.What does it cost?
Cost estimates for this credit
On each BD+C v4 credit, LEEDuser offers the wisdom of a team of architects, engineers, cost estimators, and LEED experts with hundreds of LEED projects between then. They analyzed the sustainable design strategies associated with each LEED credit, but also to assign actual costs to those strategies.
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Learn more about The Cost of LEED v4 »Frequently asked questions
See all forum discussions about this credit »Addenda
How can a project earn exemplary performance for Stormwater Quantity and Quality?
The exemplary performance requirements for SSc6.1 Stormwater Quantity and SSc6.2 Stormwater Quality listed in the LEED Green Building Design & Construction Reference Guide call for (1) a comprehensive approach to capture and treat stormwater runoff and (2) demonstrated performance above and beyond the credit requirements. To expand and clarify what these two requirements refer to, the following additional guidance is provided.SSc6.1 Stormwater QuantityTo demonstrate a comprehensive approach and performance above and beyond the credit requirements, the stormwater management strategies must:1. Address runoff from the entire development footprint of the site using Low Impact Development (LID) practices. 2. Achieve the following stormwater quantity performance:a. Case 1, Option 1: Achieve a post-development peak discharge rate and quantity that is equivalent to those calculated for the pre-Columbian site conditions.b. Case 1, Option 2: No EP available for his compliance path.c. Case 2: Achieve a 50% reduction in the volume of runoff during the 2-year 24-hour design storm.LID is defined as an approach to managing stormwater runoff that emphasizes on-site natural features to protect water quality by replicating the pre-development hydrologic regime of watersheds and addressing runoff close to its source. Examples include better site design principles such as minimizing land disturbance, preserving vegetation, minimizing impervious cover, and design practices like rain gardens, vegetated swales and buffers, permeable pavement, and soil amendments. These are engineered practices that may require specialized design assistance.SSc6.2 Stormwater QualityTo demonstrate a comprehensive approach and performance above and beyond the credit requirements, the best management practices employed must be non-structural, conforming to LID practices as defined above, and should be designed to remove at least 80% of the average annual total suspended solids (TSS) from twice the rainfall volume required for the base credit (i.e, runoff generated from 1 inch of rain in an arid climate, 1.5 inches of rain in a semiarid climate, and 2 inches of rain in a humid climate).To document compliance with these requirements, a detailed narrative or stormwater management plan summary should be provided that describes the exemplary performance approach and includes calculations that clearly highlight compliance with the exemplary performance requirements. As the exemplary performance requirements for these two credits overlap considerably, only one SSc6 EP point is available to projects.
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© Copyright U.S. Green Building Council, Inc. All rights reserved.
Requirements
Implement a stormwater management plan that reduces impervious cover, promotes infiltration and captures and treats the stormwater runoff from 90% of the average annual rainfall1 using acceptable best management practices (BMPs). BMPs used to treat runoff must be capable of removing 80% of the average annual postdevelopment total suspended solids (TSS) load based on existing monitoring reports. BMPs are considered to meet these criteria if:
- They are designed in accordance with standards and specifications from a state or local program that has adopted these performance standards.
- There exists infield performance monitoring data demonstrating compliance with the criteria. Data must conform to accepted protocol (e.g., Technology Acceptance Reciprocity Partnership [TARP], Washington State Department of Ecology) for BMP monitoring.
SITES-LEED Equivalency
This LEED credit (or a component of this credit) has been established as equivalent to a SITES v2 credit or component. For more information on using the equivalency as a substitution in your LEED or SITES project, see this article and guidance document.LEEDuser expert
Gregory Hurst
Robert Peccia & Associates
Office Manager
