PONTCHARTRAIN COASTAL LINES OF DEFENSE PROGRAM

The coast has always been our first line of defense against hurricanes for southeast Louisiana. Recognizing this, Pontchartrain Conservancy (PC) developed the Multiple Lines of Defense Strategy designed to help save our coast. In the simplest terms, this strategy highlighted below shows how natural features of our coast (like barrier islands, marshes, and ridges) compliment manmade features (like levees) to protect the Greater New Orleans area from hurricanes.

Applying this strategy, PC looked to its Comprehensive Habitat Management Plan. The CHMP consists of over 100 projects and is the blueprint for restoration of the habitats in the Pontchartrain Basin. The CHMP projects were prioritized choosing the 10 habitat restoration projects that would also provide flood protection for the Greater New Orleans area. These projects became known as the Pontchartrain Coastal Lines of Defense Program.

You can access a copy of the Pontchartrain Coastal Lines of Defense brochure here.

The Multiple Lines of Defense Strategy was developed in 2006 by PC. It describes the various features on the landscape that reduce the risk of damage from storm surge to local communities, infrastructure, and economy.

A SET OF 10 WETLAND RESTORATION PROJECTS

1. Maintain the Lake Borgne Landbridge 2. Restore the Bayou la Loutre Ridge (includes constriction of MRGO to GIWW dimensions) 3. Restore the Chandeleur Barrier Islands 4. Construct the Jefferson Parish fringe marsh buffer 5. Construct the Violet Reintroduction to maintain target salinity in LA and MS 6. Maintain and restore the Biloxi Marsh Landbridge and reefs - South 7. Maintain and restore Breton Landbridge with Caernarvon and marsh creation 8. Maintain critical marsh shorelines and ridges of the East Orleans Landbridge 9. Maintain and restore Biloxi Marsh Landbridge and barrier reefs -North 10. Maintain and enhance the Maurepas Landbridge with Maurepas Reintroduction

1. Maintain the Lake Borgne Landbridge

What: Extensive Rock armoring, local marsh creation, Intermediate marsh
Who: US Army Corps of Engineers, EPA, LSU Hurricane Center, St. Bernard Parish, DNR, Pontchartrain Conservancy
Estimated Cost: $80,000,000

Performance Goals

Flood Protection: Wetland buffer to St. Bernard levees and minimize encroachment of Lake Borgne into the MRGO
Habitat Restoration: Typical intermediate marsh nursery and fringe marsh benefiting recreational and commercial fishing

Status

March 2009 - Excellent
The Corps has completed a shoreline protection project on Lake Borgne and has plans and funds for several small marsh creation projects on the land bridge. Other CWPPRA or CIAP projects are forthcoming.

To obtain archived (no hyperlink) material email info@ScienceForOurCoast.org

Resources

• CIAP Submittal
• CWPPRA PO-30 shoreline protection project - EPA Lead
• CWPPRA PO-32 shoreline protection project - USACE Lead

2. Restore the Bayou la Loutre Ridge (includes constriction of MRGO to GIWW dimensions)

What: Constrict MRGO channel (GIWW dimensions or smaller), rebuild and re-forest natural ridge, natural ridge and intermediate marsh
Who: US Army Corps of Engineers, LSU SRC, LSU Hurricane Center, St. Bernard Parish, The Nature Conservancy, DNR, Pontchartrain Conservancy
Estimated Cost: $150,000,000

Performance Goals

Flood Protection: Impede northward movement of storm surges and reduce surge water elevation north of Bayou la Loutre ridge with soil foundation and ridge forest
Habitat Restoration: Restore the natural ridge and hydrologic barrier between the Borgne-Biloxi estuary and the Caernarvon-Terre aux Boeufs estuary, restore the Natural levee ridge habitat of oak, black willow providing refuge of indigenous ridge species

Status

March 2009 - Excellent
The Corps is currently constructing the plug in the MRGO at Bayou la Loutre, which will reduce saltwater intrusion. Shaw (engineering firm) is under Corps contract, and is now building the surge barrier at the MRGO funnel, which will reduce flood risk.  The barrier includes a floodwall across the MRGO at Bayou Bienvenue. Both the plug and floodwall should be completed this summer. Although the restoration of the Bayou la Loutre ridge is widely recognized as significant, specific restoration projects have not been developed by the state or Corps. Rebuilding the ridge is in the State's Master Plan and should be required given the Governor’s Executive Order to implement the State Master Plan. The Corps is considering ridge restoration in the MRGO Ecosystem Restoration Feasibility Study. A draft of that study is due next summer.

To obtain archived (no hyperlink) material email info@ScienceForOurCoast.org

Resources

• CIAP Submittal
• PC conceptual illustrations Bayou la Loutre ridge restorations

3. Restore the Chandeleur Barrier Islands

What: Beach nourishment with sand and shell, saline habitat
Who: US Fish & Wildlife Service, National Marine, Fisheries Service, USACE (Mobile District), Minerals Management Service, US Geological Survey (Tampa Bay Office), St. Bernard Parish, Pontchartrain Institute for Environmental Sciences, DNR, MS Dept. of Marine Resources, Pontchartrain Conservancy
Cost: PC Request $150,000,000 (Due to Hurricane Katrina this may be insufficient)

Performance Goals

Flood Protection: Reduce wave heights and wave energy entering Chandeleur Sound (fair weather and storm generated) and impacting the Biloxi Marsh, reduce storm surge elevations east of barrier islands
Habitat Restoration: Barrier Island dune and lagoon habitats, Saline marsh, bid rookery, recreational and commercial fishing, maintain benefits of National Wildlife Refuge.

Status

March 2009 - Fair
Restoration planning for the islands needs a good scientific base. The USGS, USFWS and UNO are expected to complete their study of the Chandeleur Islands this summer. We are optimistic that this study will quickly help move forward planning and construction of restoration projects for the Chandeleur Islands.

To obtain archived (no hyperlink) material email info@ScienceForOurCoast.org

Resources

• CIAP Submittal
• CWPPRA PO-27 Chandeleur Island Marsh Restoration: NMFS lead

4. Construct the Jefferson Parish fringe marsh buffer

What: Rock armoring, marsh creation, SAV habitat, reef balls, Intermediate marsh
Who: National Marine Fisheries Service, US Army Corps of Engineers, LSU Ag Center, LSU - SRC, Jefferson Parish, DNR, Pontchartrain Conservancy
Cost: PC request $62,500,000

Performance Goals

Flood Protection: Wetland buffer to levees in East Jefferson Parish by reducing risk of levee failure and reducing shoreline or berm erosion lake ward of the levee
Habitat Restoration: Establish intermediate, fringe marsh providing critical marsh nursery, recreational fishing, birding and other outdoor activities

Status

March 2009 - Fair
Jefferson Parish is reviewing alternatives to address the lake shoreline adjacent to the Jefferson Parish levee.   They are considering options to rebuild some coastal buffer with offshore breakwaters and wetland restoration.  This study is to be completed in a couple of months.  Also, PC is applying for a grant for a shoreline restoration project at the base of the Causeway Bridge (south shore).  UNO is assisting with the survey and design work.

To obtain archived (no hyperlink) material email info@ScienceForOurCoast.org

Resources

• CIAP Submittal
• East Jefferson Levee District Board morning, the Board Resolution 12-21-06
• LSU Jefferson Parish Shoreline Restoration 2006

5. Construct the Violet Reintroduction to maintain target salinity in LA and MS

What: Reintroduce Mississippi River water to achieve habitat goals of baseline, reestablish cypress forest, Swamp, intermediate to saline marsh
Who: National Marine Fisheries Service, EPA, MS Dept. of Marine Resources, St. Bernard Parish, DNR, Pontchartrain Conservancy
Cost: PC request $135,000,000

Performance Goals

Flood Protection: Maintain salinity targets to develop a denser and more mature wetland forest east of Chalmette to buffer to St. Bernard levees, and to enhance oyster growth in the outer Biloxi marsh to maintain marsh reduce surge into Mississippi Sound and Lake Borgne

Habitat Restoration: Reduce salinity intrusion into swamp or fresh marsh habitat, increase primary and secondary productivity including commercial species such as shrimp, blue crab and oysters. Typical intermediate marsh nursery and fringe marsh benefiting recreational and commercial fishing

Status

March 2009 - Good
The Violet Diversion was authorized by Congress in 2007. The State has selected Arcadis Consultants to model the diversion at Violet, Louisiana. UNO recently completed hydrologic modeling in the Pontchartrain Basin with multiple diversions in operation, including the Violet Diversion. Unfortunately, planning is slow. The State Draft 2010 Plan does not propose a start for construction until after 2012.

To obtain archived (no hyperlink) material email info@ScienceForOurCoast.org

Resources

• CIAP Submittal
• PC map Historic oyster reefs circa 1912 - 1932
• PC Memorandum Violet Diversion & model status
• UNO Violet Diversion modeling report - 2007
• USACE Bonnet Carre & Violet modeling report - 2007

6. Maintain and restore the Biloxi Marsh Landbridge and reefs - South

What: Salinity management, Oyster reef propagation (reef balls, etc.), rock armoring, marsh creation, terracing, brackish to saline
Who: US Fish and Wildlife Service, Natural Resource Conservation Service - Lead agency, St. Bernard Parish, LSU SC&E, LSU Ag Center, LA Dept. of Wildlife & Fisheries, DNR, MS Dept. of Marine Resources, Pontchartrain Conservancy
Cost: PC request $60,000,000

Performance Goals

Flood Protection: Maintain integrity of the marsh landbridge and natural ridges preventing Bay Boudreaux developing into a tidal pass or merging into Chandeleur sound which would increase storm surges in Mississippi Sound and Lake Borgne
Habitat Restoration: Preserve and restore brackish marsh including robust oyster beds throughout the outer Biloxi marsh. Develop oyster barrier reefs within the or along the Fishing Smack Bay

Status

March 2009 - Poor
Restoration of this area is recommended within the State Master Plan.  However, there are no specific projects proposed for the land bridge. In 2006, PC proposed a project with the National Marine Fisheries Service for CWPPRA, but that project was not selected.

To obtain archived (no hyperlink) material email info@ScienceForOurCoast.org

Resources

• CIAP Submittal
• PC map Historic oyster reefs circa 1912 - 1932
• PC Memorandum Violet Diversion & model status
• TNC, NOAA document value of shellfish & Reefs
• NMFS proposed CWPPRA PPL 17 project Conkey Cove

7. Maintain and restore Breton Landbridge with Caernarvon and marsh creation

What: Marsh creation (Sediment trap), land building (diversions), reefs, Intermediate to brackish marsh
Who: US Army Corps of Engineers, Natural Resource Conservation Service, US Fish and Wildlife Service, Caernarvon Inter-Agency Advisory Committee, Plaquemines Parish, St. Bernard Parish, LSU SC&E, DNR, Pontchartrain Conservancy
Cost: PC request $40,000,000 (Due to Hurricane Katrina this may be insufficient)

Performance Goals

Flood Protection: Wetland buffer to levees in St. Bernard and Plaquemines Parish by reducing storm surge height and energy
Habitat Restoration: Typical intermediate to brackish marsh nursery benefiting recreational and commercial fishing

Status

March 2009 - Fair
Several projects are being designed in the Caernarvon outfall area. A CWPPRA project which combines outfall management and marsh creation near Lake Lery is moving forward. The Corps intends to start their project using $10,000,000 appropriated in 2006  for the Caernarvon area. PC is testing the impact of nutria on marsh creation by deploying cages which prevent nutria from eating patches of marsh grass.  Additional restoration projects are needed.

To obtain archived (no hyperlink) material email info@ScienceForOurCoast.org

Resources

• CIAP Submittal

8. Maintain critical marsh shorelines and ridges of the East Orleans Landbridge

What: Conservation, local rock armoring, marsh creation for critical areas of shoreline, Intermediate marsh
Who: US Army Corps of Engineers, LSU SRC, LSU Hurricane Center, UNO – Social Sciences, Orleans Parish, St. Tammany Parish, DNR, Pontchartrain Conservancy
Cost: PC request $87,500,000

Performance Goals

Flood Protection: Reduce storm surges into Lake St. Catherine and Lake Pontchartrain by maintaining or enhancing landbridge elements of marsh and Pine Island natural ridges
Habitat Restoration: Typical intermediate marsh nursery benefiting recreational and commercial fishing, Maintain natural ridge habitat of the Pine Island ridges

Status

March 2009 - Excellent
Several projects have been approved and are being designed.   CWPPRA and CIAP projects will be built on the Lake Borgne shoreline.  Another CWPPRA project was proposed this year.  The State is considering using some of the Interstate 10 bridge concrete to stabilize the shoreline around the land bridge.  PC and the SE Flood Protection Authority East are developing a project near the Rigolets Pass.   In addition, Brazallier Island was purchased in 2008 and is now part of the Bayou Sauvage National Wildlife Refuge.

To obtain archived (no hyperlink) material email info@ScienceForOurCoast.org

Resources

• CIAP Submittal
• CWPPRA PO-22 Bayou Chevee Shoreline Protection USACE lead
• CWPPRA PO-34 Alligator Bend Marsh creation and Shoreline USACE lead

9. Maintain and restore Biloxi Marsh Landbridge and barrier reefs -North

What: Salinity management, Oyster reef propagation (reef balls, etc.), rock armoring, marsh creation, terracing, brackish to saline
Who: Natural Resource Conservation Service, US Fish and Wildlife Service, St. Bernard Parish, LSU SC&E, LSU Ag Center, LA Dept. of Wildlife & Fisheries, DNR –Coastal Restoration Division, MS Dept. of Marine Resources, Pontchartrain Conservancy
Cost: PC request $60,000,000

Performance Goals

Flood Protection: Maintain integrity of the marsh landbridge preventing Bay Boudreaux developing into a tidal pass and merging into Mississippi Sound which would increase storm surges in Mississippi Sound and Lake Borgne
Habitat Restoration: Preserve and restore brackish marsh including robust oyster beds throughout the outer Biloxi marsh. Develop oyster barrier reefs within Mississippi Sound shoreline of the Biloxi marsh

Status

March 2009 - Poor
Only one project has been proposed for this area. PC proposed that the state use Interstate 10 bridge spans for shoreline stabilization and for oyster reef restoration.   We believe this project has great promise and have informally been told the state is still considering this option.

To obtain archived (no hyperlink) material email info@ScienceForOurCoast.org

Resources

• CIAP Submittal
• PC map Historic oyster reefs circa 1912 - 1932
• PC Memorandum Violet Diversion & model status
• TNC, NOAA document value of shellfish & reefs

10. Maintain and enhance the Maurepas Landbridge with Maurepas Reintroduction

What: Conservation, River reintroductions, hydrologic restoration, marsh creation, swamp & fresh marsh
Who: EPA, Southeastern Louisiana University, Tangipahoa Parish, St. John the Baptist Parish, LA DWF, DNR, DNR – Coastal Management Division, Pontchartrain Conservancy
Cost: PC request $50,000,000 for conservation L. Pont. rim, LCA request $80,000,000

Performance Goals

Flood Protection: Reduce storm surges into Lake Maurepas and adjacent shoreline regions by maintaining or enhancing landbridge elements of swamp and fresh marsh
Habitat Restoration: Develop mature swamp and swamp canopy by increasing primary productivity. Increase productivity of fresh marsh. Enhance recreational and commercial fishing. Increase detrital export into Lake Pontchartrain

Status

March 2009 - Good
Conservation of the Maurepas Land Bridge is a prime strategy to maintain the integrity of the land bridge as a ‘line of defense’.   This is primarily to sustain the cypress forest.  Several purchases over the past few years have placed large tracts into State Wildlife Management Areas.   Most of the land bridge is now in state conservation.   Once built, the Maurepas Diversion (river reintroduction) will influence the southern end of the Maurepas Land Bridge.  Design will be complete by early 2010, however funding for construction has not been appropriated.   PC is very concerned about nutria preventing cypress re-growth in this area and may propose that the state eliminate alligator hunting on the WMA’s so that nutria will be eaten by large alligators.

To obtain archived (no hyperlink) material email info@ScienceForOurCoast.org

Resources

• CIAP Submittal
• CWPPRA PO-29 River Reintroduction into Maurepas Swamp - EPA lead

 

Resources

Maps

Map of proposed restoration habitat goals

Program Endorsements

LA WLF Resolution to Support PCLOD

Reports

Pontchartrain Coastal Lines of Defense Summary Report-Feb 2006
Pontchartrain Coastal Lines of Defense Report Version 1-Sep 2009
Pontchartrain Coastal Lines of Defense Report Card -October 2009
Pontchartrain Coastal Lines of Defense Report Card -September 2012