Karen Wiggen, RLA PGM/Planning Bob Harrington, P.E. PGM/CPIS Michael Clar, P.E. - ECOSITE

Transcription

1 Karen Wiggen, RLA PGM/Planning Bob Harrington, P.E. PGM/CPIS Michael Clar, P.E. - ECOSITE

2 Presentation Highlights Background of Grant Award What are the County s grant requirements? Maryland Stormwater Management Act of 2007 What does the Act require of local jurisdictions? Environmental Site Design (ESD) How is ESD different from current stormwater management?

3 How we got here Grant award by the National Fish and Wildlife Foundation Partners: Charles County Government (Department of PGM) Town of La Plata, and Town of Indian Head Grant objective: Wide scale implementation of low impact development practices in Charles County. Basis: U.S. Army Corps of Engineers Mattawoman Creek Watershed Management Plan; Port Tobacco River Watershed Restoration Action Strategy; and Maryland Stormwater Management Act of 2007

4 Final Products Stormwater Management Ordinance (needs Commissioner adoption) Separate Storm Drainage Ordinance (needs Commissioner adoption) SWM Review Polices and Procedures (MNCBIA/PGM Advisory Board) Charles County Environmental Site Design Manual (MNCBIA/PGM Advisory Board)

5 Timeline Public Kick-off Meeting (January 2009) Focus Groups in 2009 to Review Discuss Draft: June 24 th at La Plata Town Hall, July 15 th at Indian Head Village Green Pavilion & July 30 th at County Govt. Building Submittal to Maryland Department of the Environment for their review ( November 11, 2009) Public Adoption Process (public meetings & work sessions) Engineer & Inspector Training (February 19, 2010) (to be held at College of Southern Maryland for Charles County as well as private engineers and inspectors) Effective Date of new Ordinance / Regulations May 4, 2010* *Applies to all new and redevelopment plans that do not have final Erosion and Sediment Control and Stormwater Management plan approval

6 Requires that all projects design stormwater management using Environmental Site Design (ESD) techniques to the Maximum Extent Practicable (MEP) Requires all projects to follow a stepwise (3 step) plan review process Applies to all projects that do not have stormwater management and erosion and sediment control plan approval on or before May 4, 2010.

7 ESD means using small-scale stormwater management practices, nonstructural techniques, and better site planning to mimic natural hydrologic runoff characteristics and minimize the impact of land development on water resources ESD implementation accomplishes Low Impact Development (LID) ESD includes: Optimizing conservation of natural features, such as, drainage patterns, soils, and vegetation Minimizing use of impervious surfaces, such as paved surfaces, concrete channels, roofs, and pipes Slowing down runoff to maintain discharge timing and to increase infiltration and evapotranspiration

8 MAXIMUM EXTENT PRACTICABLE (MEP) - Means designing stormwater management systems so that all reasonable opportunities for using ESD planning techniques and treatment practices are exhausted and, only where absolutely necessary, a structural best management practice (i.e. pond) is implemented

9 All projects must follow a stepwise (3 step) process Concept Plan Site Development Plan Final Stormwater Management Plan Reviews must be coordinated with local agencies to include: Soil Conservation District Planning & Growth Management Public Facilities

10 ESD Practices ESD practices will change the look of stormwater management Move from use of large end of pipe pond technology to many microscale practices that are integrated into the site s landscape Separated Stormwater New look will be more environmentally friendly and sustainable and also be more aesthetically pleasing Integrated Stormwater

11 ESD Practices Group 1: Alternative Surfaces Green Roofs/ Permeable Pavements Group 2: Nonstructural Practices Disconnection of rooftop runoff / Disconnection of non-rooftop runoff / Sheetflow to conservation area Group 3: Micro-scale Practices Rainwater Harvesting / Submerged Gravel wetlands Landscape Infiltration / Infiltration Berms Dry wells / Micro-bioretention / Rain gardens Swales / Enhanced Filters

12 Group 1: Alternative Surfaces- Green Roofs MDE Building in Baltimore National Aquarium (Balt Sun Photo) BP Gas Station (Baltimore Sun Photo) Eastern Village Condos in Silver Spring

13 Group 1: Alternative Surfaces - Permeable Pavement O.C. McDonald s brick pavers La Plata Starbucks porous asphalt Leonardtown Public Parking Lot brick pavers Waldorf Old Line Center - porous pavement St. Mary s City -honeycomb pavers

14 Group 2: Non-Structural Practices Disconnection of Rooftop Runoff and Non-Rooftop Runoff Disconnected rooftop runoff Connected downspout flowing onto pavement Disconnected non-rooftop runoff

15 Group 2: Non-Structural Practices Sheetflow to Conservation Area Development Stream Buffer Stream

16 Group 3: Micro-Scale Practices Rainwater Harvesting (Cisterns & Rain Barrels) Cisterns for large scale collection and reuse Chesapeake Bay Foundation, Annapolis Rainbarrels for residential use

17 Group 3: Micro-Scale Practices Submerged gravel wetlands and Landscape Infiltration Submerged Gravel Wetland These practices fit into limited spaces, typically set aside for landscaping and roadway medians. Good for areas with high water tables and poor soils. Landscape Infiltration

18 Group 3: Micro-Scale Practices Infiltration Berms and Dry Wells Infiltration Berm Dry Well PA Dept of Env Protection

19 Group 3: Micro-Scale Practices Micro-Bioretention and Enhanced Filters Tacoma Park, Photo by AMT Photo of urban planter boxes by Liptan, Portland Curb-cuts allow water into biorention area

20 Group 3: Micro-Scale Practices Rain Gardens Prince George s County Functional Landscaping

21 Tacoma Park, MD Photo by AMT Group 3: Micro-Scale Practices Swales Seattle, WA Grass Channel Charles County

22 ESD Case Study: Office

23 ESD Case Study: Small Commercial

24 l ESD Case Study: Hotel

25 ESD Case Study: High Density Residential

26 Comments / Questions SWM Ordinance/ESD Manual/Storm Drainage Ordinance