Delaware Bay Main Channel Deepening Project

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Delaware Bay Main Channel Deepening Project

• Kelly Island
• Restoration Project

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Location Map Location Map Location Map Location
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Map Location Map Location Map
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High marsh
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• Project Objectives
• Restore intertidal wetland acreage
• Protect existing marsh
• Create habitat
• Avoid ecological impacts
• Protect Mahon River entrance
• Use dredged sediments
• Create a stable long-term project

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• Project Features
• 60 acre wetlands (240K cy silt 460K cy sand)
• Offshore Dike (1.7 M cy sand) 5000 ft of sandy
  beach
• Geotextile tube core for overwash protection

Sheetpile Groins
Groins to limit transport away from
site Protection of southern tip of island North
outlet possible south outlet
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Distorted vertical-scale profile
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Undistorted profile
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Sheetpile Groins
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• Maintenance Areas

Sheetpile Groins
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• Maintaining Habitat Areas
• Marsh
• Topographic contouring for habitat
• Channels, ponds, mounds, flats

• Adaptive management
• water flow, plantings, or eradication
• Beach
• Obstructions or hindrances to crabs shorebirds
  

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• Maintaining Structures
• Offshore dike
• Replace sand every 10 years
• Breach repairs (to bury geotextile tube)
• Outlet works
• Clogging, deterioration
• Groins
• Repair as necessary
• Dredging Mahon River Channel
• 40,000 cubic yards every 3 years

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• Monitoring Plans
• Annual visual inspections
• Beach survey
• Profiles along length of dike
• Aerial photographs
• Habitat
• Vegetation
• Fisheries
• Birds
• Other