Pavement Panel: The Big Gray Thing in the Room Accelerating GSI investment at the nexus of roads and toxic runoff The Problem: Toxic runoff can impact human health and ecological systems Stormwater runoff is largest source of pollution to Puget Sound • 75% of the toxic chemicals entering Puget Sound are carried by stormwater runoff • Despite the amount of polluted stormwater coming off bridges and roadways, very little is spent on retrofitting 25%-35% of an average city is Right of Way Most ROW was built before modern stormwater codes 75% of pollutants in Puget Sound are from hard urban surfaces Kids attend schools so close to busy roads that traffic exhaust poses a health risk. Urban heat islands are a double- whammy for health. The heat poses health risks to the elderly, people with heart disease and diabetes. The hottest places in the city are also more polluted. Southern Resident killer whales are on a course headed for extinction with key contributors being Chinook salmon prey shortage & high levels of toxic chemicals from stormwater runoff affecting Orca immune systems, health and reproductive rates. Multiple Benefits of Green Stormwater Infrastructure An analysis of green and grey infrastructure in Philadelphia revealed that the option including GSI was clearly the better financial choice for managing stormwater. Cost: $2.4 billion Co-Benefits: $2.85 billion Cost: $3.8 billion Co-Benefits: $0.122 billion Issues and Constraints to GSI Implementation Diverting Pollution from Community Assets Perceived GSI Limited Access Limited Performance to Funding Pollutant Data Risk Ongoing Constrained Maintenance right-of-way of GSI Response #1: Build a Movement • Cross-Sector Coalition of 125+ Partners • Accelerating collaboration at the watershed scale, with a focus on polluted stormwater runoff in the Puget Sound • Coordinate and communicate best available science • Engaging business community and private land owner; inspire voluntary action • Push for innovation – going above and beyond Response #2: Science-Based Approach Total Copper Polycyclic Total Suspended Minority and Low- Aromatic Solids Income Hydrocarbons Populations (combustion related pollutants) Ellen Southard, Salmon Safe Susan McLaughlin (SDOT) & Shanti Colwell (SPU), City of Seattle Peg Staeheli, MIG | SvR Q&A GREEN BRIDGES clean water @ the center of the universe CLEAN H20 FOR THE CENTER OF THE UNIVERSE SPECIES IMPACT Chinook Sockeye Coho Kokanee Steelhead Trout DATA ONE (PHASE 1) UNOCCUPIED ROOF RUNOFF BRIDGE RUNOFF WATERSHED OCCUPIED ROOF RUNOFF (PHASE 2) FREMONT BIOSWALE SITE (PHASE 3) HIGHWAY 99 RUNOFF HIGHWAY 99 RUNOFF HIGHWAY 99 RUNOFF HIGHWAY 99 RUNOFF HIGHWAY 99 RUNOFF HIGHWAY 99 RUNOFF WHAT’S IN THE WATER? Aurora Bridge Stormwater Quality in Comparison to Other Stormwater Datasets 2000 1800 1600 1400 Aurora Bridge Median 1200 Aurora Bridge Mean 1000 I-5 Hwy 520 Median NSQD Median 800 California Hwy Mean 600 400 200 0 TSS (mg/L) Total Zinc (µg/L) Total Copper (µg/L) Total Lead (µg/L) DATA 1 IMPACT MIGRATION OF SALMON 6 total bridges Ballard Bridge Ballard Bridge Composite Decking with Gutter Ballard Bridge Ballard Bridge Fremont Bridge Composite Decking with North Gutter South Fremont Bridge I-5 North Ship Canal Bridge I-5 North Ship Canal Bridge I-5 South Ship Canal Bridge I-5 South Ship Canal Bridge I-5 South Ship Canal Bridge I-5 South Ship Canal Bridge University Bridge University Bridge Composite Decking with Gutter University Bridge Montlake Bridge Composite Decking with Gutter North South Montlake Bridge 3M 11M 4M 98M 1M 200K Relative Average Annual Runoff Volumes Next Steps? • Understand Ecology • Public Awareness / Engagement • Refine Costs / Feasibility • Identify Funding Sources • Advance Design THANK YOU BOEING & TNC www.salmonsafe.org [email protected] Green Stormwater Infrastructure Urban Street Design in Seattle SHANTI COLWELL, PE GSI PROGRAM MANAGER SUSAN MCLAUGHLIN, AICP URBAN DESIGN MANAGER Presentation Outline • NACTO Urban Street Stormwater Guide • Streets Illustrated – Seattle’s new street design manual • GSI Design Manual – Capital project tool • Policy support for GSI partnerships – Seattle Department of Transportation - Complete Streets – Seattle Public Utilities GSI program • Examples of SDOT-SPU partnership projects NACTO Urban Street Stormwater Guide • Collaboration between city transportation, public works and water departments to advance discussion about how to design and construct sustainable streets. • Provides national best practices for sustainable stormwater management in the public right-of- way • Sheds light on effective policy and programmatic approached to starting and scaling up green infrastructure 12 New Street Types Curbless Street Types & Alternative Sidewalk Design • Provide a barrier free, safe pedestrian route, • Minimize the removal of mature vegetation, • Enable green stormwater infrastructure above Stormwater code requirements and/or • Allow for more extensive sidewalk improvements (1 block minimum) compared to conventional concrete curb and sidewalk construction. Urban Curbless Residential Curbless 55 Green Stormwater Infrastructure- Design Guidance- Side slopes Green Stormwater Infrastructure- Design Guidance- walled bioretention Standard GSI Details & Specs . Standard details – Pervious concrete sidewalks – Bioretention sections (earthen slopes and vertical walls) – Bioretention curb cuts, presettling cells, pit drains, drilled drains . Specifications – Bioretention soil – Pervious cement concrete pavement – Slotted underdrain pipe and aggregate blanket 58 GSI Design Manuals . Manuals to support CIP design in the ROW – Volume I: Project Initiation Phase – Volume II: Options Analysis – Volume III: GSI Design Phase – Volume III: Construction – Volume IV: O&M – Volume V: Monitoring 59 Site Design - Bioretention with vertical walls vs side slope Downtown neighborhood Residential neighborhood Neighborhood Co-benefits water pollution prevention + Traffic Calming New Street Trees Beauty Sidewalk NDS Partnering Program Partner with SDOT, Internal SPU departments (Localized Flooding), Grassroots/Communities, and Private Entities, to identify opportunities and implement GSI Seattle’s Complete Streets policy • Complete Streets policy adopted by City ordinance in 2007 Insert image • “Transportation improvements will include an array of facilities and amenities that are recognized as contributing to Complete Streets, including: … street trees, landscaping and natural drainage” Long Term Control Plan Pipers Creek Watershed Thornton Creek - NDS Partnering Program Watershed Streets shown in pink are potentially technically feasible for a natural drainage system. IMPORTANT: SPU is funded to build projects on about 4% of these blocks. This means we will be able to build natural drainage systems on a small sub-set of potentially feasible blocks. Begin Begin Watershed Design Construction Longfellow 2017 2019 Thornton 2018 2019 Pipers 2019 2020 Longfellow Creek Watershed SEA Street – First Major Project Broadview Green Grid Natural Drainage System at 107th from Palatine facing west, Before construction Broadview Green Grid Natural Drainage System at 107th from Palatine facing west, After Construction Ballard Natural Drainage Systems Project – Shortened Crossings Schools Neighborhood Greenways 30th Ave NE Sidewalk and NDS Project Take advantage of the area under the sidewalk – Ballard NDS Discussion / Questions More information or follow-up questions: www.seattle.gov/util/naturaldrainage Shanti Colwell [email protected] Susan McLaughlin [email protected] 3rd Annual Puget Sound Green Infrastructure Summit Peg Staeheli MIG | SvR 3rd Annual Puget Sound Green Infrastructure Summit Q&A.