Thinking About Clean Water and Development
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The document discusses the impact of development on clean water, emphasizing the importance of watershed management and low impact development (LID) practices. It highlights the negative effects of urbanization, including increased runoff and water quality issues, and outlines strategies for responsible land use planning, construction, and management of existing developments. The presentation aims to provide decision-makers with insights on promoting sustainable practices to protect water resources and mitigate environmental impacts.
Thinking About Clean Water and Development
- 1. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Anne Kitchell Horsley Witten Group, Inc. April 2, 2014 2014 Decision Makers Workshops: Construction and Clean Water Thinking about Clean Water & Development
- 2. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 3. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 4. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 5. Horsley Witten Group, Inc.Horsley Witten Group, Inc. A quick trip to www.savebuzzardsbay.org
- 6. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 7. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 8. Horsley Witten Group, Inc.Horsley Witten Group, Inc. On today’s agenda • The impacts of development • Watershed decisions for decisions makers − Where to build − How to build − How to manage “the built” • What is coming…
- 9. Horsley Witten Group, Inc.Horsley Witten Group, Inc. The visible impacts from existing development
- 10. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Urbanization results in increased surface runoff BEFORE AFTER
- 11. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Watershed impacts at~10% impervious are well documented: • Water quality issues • Impacts to biological communities • Increased flooding • Stream erosion • Loss of recreational uses • Shellfish bed closures • Reduced recharge & baseflow • Wetland & contiguous forest loss • Increased % managed lawn
- 12. Horsley Witten Group, Inc.Horsley Witten Group, Inc. % Impervious cover is an indicator
- 13. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Impervious Cover at the Community Scale
- 14. Horsley Witten Group, Inc.Horsley Witten Group, Inc. 8-10% 20% 30%> 65% < 5% As seen in the stream % impervious
- 15. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Time (hrs) Runoff(cfs) Post-development More runoff volume Arrives faster Pre-development Runoff Hydrograph
- 16. Horsley Witten Group, Inc.Horsley Witten Group, Inc. 2 great (but dated) references
- 17. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Runoff WQ data from~3,800 storm events, 17 states
- 18. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 19. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Streams with <50 sq miles drainage upstream 0 10 20 30 40 50 60 70 80 90 100 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 % IC Upstream %ofReference Community n=125 Meet WQC Fail WQC 12% IC Threshold % of Reference Community compares 7 metrics- Taxa Richness, Modified HBI , Scraper/Filterer, EPT/Chironomidae, % Dominant Taxa, EPT Index, Community Loss Bellucci, CTDEP Linking the Bugs to IC
- 20. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Note: Data averaged from existing Massachusetts Estuaries Project Reports Contour plots of modeled total nitrogen concentrations (mg/L) in Three Bays. Source: MEP 2006 Pre-colonial Present Day Future Buildout
- 21. Horsley Witten Group, Inc.Horsley Witten Group, Inc. David Johnson and Kate Morkeski load a device that feeds fertilizer into the salt marsh on Plum Island. BOSTON GLOBE OCTOBER 18, 2012 http://www.mbl.edu/tide/data/
- 22. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 23. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 24. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Watershed Decisions • Where we build – Land use planning – Land conservation – Buffers for protected areas • How we build – Site Design – Construction – Stormwater/Wastewater • How we manage what has been built – Retrofit/Redevelopment – Pollution prevention
- 25. Horsley Witten Group, Inc.Horsley Witten Group, Inc. How would you rate your land use planning from a water resource protection perspective?
- 26. Horsley Witten Group, Inc.Horsley Witten Group, Inc. How valuable are your local wetlands? Source: Buzzards Bay Coalition website
- 27. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Do you rely on minimal state protections or more stringent local bylaws?
- 28. Horsley Witten Group, Inc.Horsley Witten Group, Inc. What are your disturbance thresholds for ESC?
- 29. Horsley Witten Group, Inc.Horsley Witten Group, Inc. The problem with how we build • More and more marginal sites are in play • Not enough consideration for existing site topography • Lack of respect for native vegetation and topsoil • Cramming as much on site as possible based on lot lines and zoning rather than site constraints • Over-reliance on engineered black boxes
- 30. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Conventional LID/New Urbanism Is consideration of LID required in your local regs?
- 31. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Time (hrs) Runoff(cfs) Post-development More runoff volume Arrives faster Pre-development Runoff Hydrograph Post-development with detention basins to “match the peak” Post-development (with LID)
- 32. Horsley Witten Group, Inc.Horsley Witten Group, Inc. BMPs used at this site eliminated offsite runoff Bioretention Bioretention Permeable Paver Infiltration Chambers
- 33. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Take a look when its raining…
- 34. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 35. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Notable Local Porous Asphalt Applications
- 36. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 37. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Which of these best exhibits the LID spirit? A B C D
- 38. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Lacey & Arrowhead LanesConventional vs LID?
- 39. Horsley Witten Group, Inc.Horsley Witten Group, Inc. GI practices
- 40. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 41. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 42. Horsley Witten Group, Inc.Horsley Witten Group, Inc. How is stormwater managed here?
- 43. Horsley Witten Group, Inc.Horsley Witten Group, Inc. cluster layout Jordan Cove, CT -12 lots clustered on 6.9 acres - Designed to minimize site runoff Low- mow areas Bioretention cul-de-sac grassed swales pervious & shared drivewaysRain gardens Low Impact Development Does it really work?
- 44. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Low Impact Development Does it really work? Conventional LID Cluster Glen Brook Green (Jordan Cove) Research/Demo Project
- 45. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Are you settling for last year’s Big Box?
- 46. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Grants Block Retrofit - Providence, RI Morris Beacon Design Are you taking advantage of redevelopment opportunities?
- 47. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Cottages on Greene, East Greenwich, RI Union Studio, Morris Beacon Design
- 48. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Which wastewater systems are you promoting?
- 49. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 50. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 51. Horsley Witten Group, Inc.Horsley Witten Group, Inc.
- 52. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Are PRBs in your future?
- 53. Horsley Witten Group, Inc.Horsley Witten Group, Inc. What’s Coming? • Cape Cod Commission 208 Project • Draft Small MS4 Stormwater Permits for Massachusetts: – Evaluate development codes for LID barriers – Annual tracking of impervious cover – Retrofit inventory for municipal properties – Program linked to impaired waters – Stormwater standards for entire MS4, not just within wetland jurisdiction • Trends in new Stormwater Manuals • Stormwater Utilities? • Local LID by-laws?
- 54. Horsley Witten Group, Inc.Horsley Witten Group, Inc. City of Attleboro – Site Design Criteria A. Use LID measures to the Max Extent Practicable B. Document Planning Process 1. Identify and map critical resources 2. Delineate potential building envelopes that avoid these resource areas C. Document % Natural Open Space Retained D. Minimize Impervious Surfaces and Document % of Site Imperviousness E. Disconnect Impervious Surfaces and Document % of Effective Impervious Cover F. Document Use of Applicable Site Design Features
- 55. Horsley Witten Group, Inc.Horsley Witten Group, Inc. How can you require LID??!
- 56. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Can we have it all? • Where to build • How to build • How to manage what’s been built
- 57. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Us at night from space (NASA, 2012)
- 58. Horsley Witten Group, Inc.Horsley Witten Group, Inc. Anne Kitchell Horsley Witten Group, Inc. April 2, 2014 2014 Decision Makers Workshops: Construction and Clean Water Thinking about Clean Water & Development Questions?