Salmon Safe and Stormwater LID Practices

Transcription

1 Salmon Safe and Stormwater LID Practices Tye Simpson, PE, LEED AP Director of Engineering /Principal

2 Only 22 of at least 37 historic Chinook populations remain. - State of the Sound 2007, Puget Sound Action Committee Puget Sound Ecosystem Overall trajectory continues to be one of decline, with continuing harm to our waters... - State of the Sound 2007, Puget Sound Action Committee 65 to 75% of native land cover needs to be preserved to retain proper conditions for salmonids DOE Stormwater Manual -Salmon are a key indicator species of the overall health of the health of the Puget Sound

3 Salmon Safe Salmon-Safe is an independent 501(c)3 nonprofit organization. Certification is based on rigorous ground inspection by independent expert certifiers. The Salmon-Safe label on a product means it was created using healthy practices that keep Pacific Northwest rivers clean enough for native salmon to spawn and thrive.

4 Salmon Safe Development Stages 1. Project inventory and assessment 2. Site planning 3. Site design 4. Site construction 5. Site maintenance and monitoring Collaborative effort at each phase between owner, designer and assessment team.

5 LID and Salmon-Safe Low Impact Development practices (LID) seeks to more closely mimic predevelopment hydrologic functions utilizing natural site features Shift from structural to source approach for stormwater management Goal is to prevent measurable harm to aquatic systems development Effective impervious area

6 PCC Market Existing site information Redevelopment site Discharges to Puget Sound Local code does not trigger stormwater treatment Salmon Safe Accreditation

7 Bioretention (rain garden) What is bioretention? Plant, soil, microbe mix filtering Absorbs runoff 30% of soil volume Infiltration and evapotranspiration LID Approach Rain Garden Stormwater Application Flow control Treatment

8 Bioretention Example Scope of work Replacing existing parking stalls with bioretention cells to achieve Salmon Safe accreditation. Center Rain Garden

9 Bioretention Project Example

10 Green Roof Growth medium, vegetation and drainage layers promote stormwater retention and evapotranspiration. Stormwater Design Application Flow control Reduce Peak Runoff (5-80%) Reduce runoff Volume (65-95%)

11 Green Roof Example New Townhome development in Seattle Met City of Seattle Flow Control Requirements using Green Roofs and Porous Pavement

12 Vegetated Roof Project Example Project benefits The reduction in surface runoff provided by the green roof and porous pavements will eliminate the need for an underground detention facility on the project site Replaced 70 of 48 diameter pipe ($15,000-$20,000) Approximate green roof cost ($35,000 - $40,000)

13 Cost Comparison Added Benefits/Long Term Savings Longer Roof Life (30 50 years) Heating(1%)/Cooling(6%) Costs Increase Property Value Incentives King County Incentives for Built Green Seattle Green Factor Requirements Portland Floor to Area Ratio Increase NYC - $4.50 /sf tax incentive = 25% of cost Germany Able to compete with traditional roofing due to tax incentives and an established green roof market.

14 Maluan Bay Wetland Restoration Xiamen, China 1.75 square kilometer site Bay is currently degraded with poor WQ and prone to floods Dam at bay limits seawater exchange Wetlands will serve as an educational and recreational resource Natural system of stormwater treatment and flow control Design for wetlands restoration work completed by Belt Collins in 2007 Estimated construction cost is US $10 million

15 Thank You Contact Tye Simpson at (206)