Transcript Staten Island Bluebelt

Staten Island Bluebelt
NYC Department of Environmental Protection
July 2,2010
Staten Island Bluebelt
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Staten Island Bluebelt Watersheds
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Project Background
South Richmond, Staten Island:
• Last large unsewered part of
New York City.
• Last significant stand of wetlands.
• Failing septic systems and street
flooding.
• Need for new drainage plans that:
– Provide necessary infrastructure.
– Preserve wetlands.
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Project Background
South Richmond, Staten Island:
• Drainage plans dating from the
1960’s assumed full sewering
eliminating all wetlands.
• Public policies to protect wetlands:
– NYSDEC freshwater and tidal
wetland regulations.
– SSRDD enacted Open Space
Network.
– City and state parks created.
• How to preserve wetlands while
providing drainage infrastructure?
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Staten Island Bluebelt Program: Overall Strategies
• Develop storm water management
system utilizing existing wetlands.
• Collect street runoff in storm
sewers; improve capacity of
hydraulic structures.
• At sewer-wetland interface, use
BMP's to mitigate impacts of urban
runoff and local flooding.
• Build separate sanitary sewer
system.
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Typical Schematic of Bluebelt Drainage Plan with BMP's
1. Extended Detention
Basin
Storm Sewers
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Outlet
Stilling
Basin
Extended
Detention
2. Pocket Wetland
Existing Pond
Sand Filter
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3. Sand Filter
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State
Wetland
Boundary
NYCDEP
Bluebelt
Boundary
Micropool
4. Retrofit of Existing
Pond
NYC Park Boundary
Lower
Pool
Micropool
5. Outlet Stilling Basin
Forebay
Upper
Pool
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6. Culvert
Reconstruction
Forebay
Micropool
Constructed
Wetland
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7. Meandering Stream
8. Stream Restoration
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Staten Island Bluebelt Program: Planning Process
Evaluation of
Alternatives
Interagency
Coordination
Drainage Plan
Public
Presentations
Impact Analysis
Draft Environmental
Impact Statement
Public
Review
Final Environmental
Impact Statement
Regulatory
Agency
Review
Final
Designs
Permitting
Construction
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BMP RC-4: Construction Sequence
Step 1: The site is cleared of debris and brush.
Step 2: The land is excavated and graded to form the
desired topography for the new wetlands.
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BMP RC-4: Construction Sequence
Step 3: For subsurface preparation, a Claymax
liner, subsoil and topsoil are overlaid.
Step 4: Erosion control mat and wetland plantings
are installed.
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BMP RC-4: Construction Sequence
Step 5: Storm water is introduced into the
constructed wetland.
Functioning constructed wetland after one growing
season.
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Bluebelt Field Management
• Vactor Operations
• Maintenance Accessways
• Perimeter Treatments
• Field Operations
• Adopt-A-Bluebelt
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Vactor Operations
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Maintenance Accessways & Perimeter Treatments
Maintenance Accessways
Perimeter Treatments
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Adopt-A-Bluebelt Program
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