Lake Raleigh Wetland Creation Feasibility Study

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Lake Raleigh Wetland CreationFeasibility Study

• NC State Centennial Campus
• Melanie Carter, Jennifer Burdette, Amanda Jones

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Project Description

• Purpose
• Determine if a wetland could be
• created in a designated open space
• on Centennial Campus
• Proposed Project
• Riverine Wetland Creation
• -- Groundwater, stormwater, and
• overbank flow inputs
• -- Native wetland vegetation
• -- Wildlife Habitat
• Pedestrian Greenway and Access
• History
• Stormwater pond and proposed
• wetland location built in early 1990s

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Feasibility Study Components

• Existing Conditions
• Site Description and Land Use
• Physical Natural Resources
• Soils
• Hydrology
• Vegetation
• Geology
• Flood Hazard
• Cultural Resources

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Feasibility Study Components (contd)

• Chain-of-Title
• Environmental Hazard Assessment
• Jurisdictional Issues
• Waters of the US (Section 404)
• Protected Species
• Riparian Buffers
• Constraints

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Existing Site Conditions
Site Description Land Use

• Study Site (2 acres)
• Semi-natural landscape with
• planned pedestrian trail
• West Boundary
• Perennial Stream and Forebay
• East Boundary
• Herbaceous Upland Slope

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Existing Site Conditions Soils
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Existing Site Conditions Soils
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Existing Conditions -- Hydrology
DETAIL
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Existing Site Conditions
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Jurisdictional Issues

• Area of construction located above ordinary high
  water mark of perennial stream and does not
  contain jurisdictional wetlands
• No Section 404/401 permit from US Army Corps of
  Engineers or NC Division of Water Quality
  required
• Area for proposed wetland creation located within
  Neuse River Basin Riparian Buffer
• No Neuse River Riparian Buffer Compliance
  required from NC Division of Water Quality

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ConceptualWetland Design
DETAIL
Proposed Levee

• Create level area east of
• stream channel
• Divert ephemeral
• drainage through
• constructed wetland
• Build a low levee along
• perennial channel to
• detain portion of
• ephemeral drainage

Area to be Leveled
Ephemeral Drainage
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Conceptual Wetland DesignCross-section
Pedestrian Trail
Existing Grade
Proposed Grade
Seasonal High Water Table
Perennial Stream
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Suggested Wetland Plants
Lizards Tail
Buttonbush
Spicebush
Jack-in-the-Pulpit
Swamp Rose
Photos courtesy of USDA PLANTS Database http//pla
nts.usda.gov/
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Project Constraints

• FEMA 100-yr Floodplain
• Boundary (Red)
• Sewer Line Amendments
• (Blue)
• Grading Costs (Gray)
• Pedestrian Greenway
• Access
• Maintenance