Kari Mackenbach, Green Initiatives Practice Leader, URS Christine Worley, URS Flood and Stormwater Mitigation Using Green Infrastructure

Incorporate Green Infrastructure What is Green Infrastructure? How does it relate to stormwater and flood management? What are the site selection criteria? What are costs and operation and maintenance concerns?

Natural and managed green areas in both urban and rural settings,Natural and managed green areas in both urban and rural settings, Strategic connection of open green areas,Strategic connection of open green areas, Treating rainwater as a resource and not as trash to be discarded as quickly as possible,Treating rainwater as a resource and not as trash to be discarded as quickly as possible, Transforming “grey” infrastructure to green through restoration of watersheds to slow and store water, andTransforming “grey” infrastructure to green through restoration of watersheds to slow and store water, and Providing multiple benefits for people.Providing multiple benefits for people. Green Infrastructure

What Else Can Green Infrastructure Do? Help communities come closer to attaining their requirements (CWA, MS4, NPDES, CSO, Chesapeake Bay TMDL, etc.)Help communities come closer to attaining their requirements (CWA, MS4, NPDES, CSO, Chesapeake Bay TMDL, etc.) Enhance public perception (sustainable cities)Enhance public perception (sustainable cities) Leverage State and Federal program dollars (brownfield redevelopment)Leverage State and Federal program dollars (brownfield redevelopment) Opportunity to “marry” two forms of public work effort (street, sidewalks, stormwater management)Opportunity to “marry” two forms of public work effort (street, sidewalks, stormwater management)

Street Stormdrain House Driveway Even your home has a big impact on stormwater runoff

Street Stormdrain 1,500 s.f. house (& patio) x 1” rain = 925 gallons of runoff 1,000 s.f. driveway x 1” rain = 617 gallons of runoff 2,500 s.f. “impervious” x 1” rain = 1,542 gallons of runoff + “Green Concrete” Compacted Lawn 8,390 s.f. “impervious” x 1” rain (if infiltrates first ¼” of rain) = 3,880 gallons of runoff In a 1” rainfall Potential Runoff: 5,422 gallons

Where can rain soak in?

Q - How Do We Protect Our Streams? A - Manage How Stormwater Runs Off the Landscape Photo: Rusty Schmidt

Distributed Stormwater Features Regional Traditional Techniques Distributing Stormwater Controls Close to Runoff Sources

Green Roof Applications

Pervious Infrastructure

Rain Gardens & Bio-Infiltration Devices

Green Infrastructure in Your Backyard! Local Challenges Local Opportunities

CONSTRUCTING GREEN SOLUTIONS ON EVERY STREET

RESIDENTAL RETROFIT VISUAL

RESIDENTIAL RETROFIT RAINGARDEN

RESIDENTIAL RETROFIT- PERVIOUS PAVERS

Green infrastructure does not replace gray infrastructure. Green infrastructure does not replace gray infrastructure. $ $ $ Can reduce the capital costs and O & M costs of gray technology. Can reduce the capital costs and O & M costs of gray technology.

The Green Behind the “Green” Green Infrastructure Type Installation Costs Operation and Maintenance Life Cycle Costs Life Cycle Costs Rain Gardens$5-7 sq. ft. $12-15 sq. ft. minimal Annual Mulching and Weeding $ sq. ft Pervious Pavement$20-35 sq. ft.minimal Fewer repairs, longer overall lifespan, yearly vacuuming/ pressure washing $0.15 sq. ft Green Roof Applications$30 sq. ft. $12-15 sq. ft. great to minimal Conventional roof yrs, green is double or triple that life cycle, watering needed until established. Rain Barrels$35-75great No maintenance, reduce water bills Constructed Wetlands$6-20 sq. ft.minimal Replace pretreatment components 3-5 yrs, weed invasive plants $ yr

RIGHT-SIZING STRATEGY Downspout Disconnection Infiltration Trenches & Dry Wells Bio-infiltration Swales Rain Gardens Pervious Pavers Green Roofs High Cost Effectiveness Lower Cost Effectiveness

Burnsville, MN Paired Study of Residential Street Runoff Control Diagram courtesy of the City of Burnsville, MN from their Burnsville Stormwater Retrofit Study

17 Rain Gardens Installed Burnsville, MN Diagram courtesy of the City of Burnsville, MN from their Burnsville Stormwater Retrofit Study 5.3 acres treated and 7.5 acres controlled Average treated lot <.5 acres Average total rain gardens < 1 acre

Burnsville, MN AFTER BEFORE Photos Courtesy of Rice Creek Watershed District Residential Neighborhood Rain Garden Retrofits Long-Term Monitoring Neighborhood Application

Burnsville, MN Blue: Control Red: With Rain Gardens Diagram courtesy of the City of Burnsville, MN from their Burnsville Stormwater Retrofit Study

Create a “First of its Kind”Create a “First of its Kind” Municipal scale rain gardenMunicipal scale rain garden Educate the publicEducate the public Design model for rain gardensDesign model for rain gardens Balances security and opennessBalances security and openness Low impact/low maintenanceLow impact/low maintenance Use innovative design measuresUse innovative design measures Site Specific/Neighborhood Application FEMA Supported, FEMA Funded.

Regional Applications Large Cities Initiatives Opportunities, Incentives & Regulatory

Educating the public about water quality, sewer and stormwater concernsEducating the public about water quality, sewer and stormwater concerns Promoting green solutionsPromoting green solutions Encouraging funding for required sewer and stormwater improvementsEncouraging funding for required sewer and stormwater improvements Kansas City, MO

Montgomery County, MD RainScapes Program Provides rebate rewards to property owners for LID practices

LOUISVILLE, KY. OVERVIEW Flood Protection Wastewater Treatment Stormwater Management

EVALUATION OF GREEN VS. GRAY  Develop Case Study Template  Cost per Gallon  Gallons Removed  Long-term Trends  Standardize Design Criteria and O&M  Standardize Green Modeling Parameters  Target Pilot CSO Basins for Right-Sizing CLEAN, GREEN, GROWING COMMUNITY

GREEN TOOLS

COLLABORATION ON GREEN

FIRST CRADA COMMUNITY 3 Year Effort-potential for up to 10 years EPA’s involvement in Green Infrastructure validation process Establish gallons removed compared to gray Evaluate and establish long term trends Standardize Design Criteria/O&M Standardize Modeling Parameters Other Ancillary Benefits Partner with University of Louisville

US EPA ORD PARTNER Monitoring Lead GMP Selection QA/QC

MONITORING IN LOUISVILLE

CSO 130 RESULTS OptionGray CostGreen Cost Total CostPOST AAOV POST # OF / YR Gray Only$1,077,000$0$1,077, MG 8 Green Only (Option 1 – GMPs 0, 10, 11, 13, 21) $0$129, MG 7 Green Only (Option 2 – GMPs 0, 10, 11, 12,13, 14, 17,19, 21 ) $0$342,000 *Pendi ng Final Model Run Existing AAOVExisting # OF / YR 0.84 MGD9

Wrap UP Green Infrastructure can: Be implemented on a site, neighborhood, or regional level Help manage flooding and stormwater Protect our streams Be cost effective Provide multiple benefits Help communities meet environmental requirements Improve public perception

Questions? Christine Worley – Kari Mackenbach –