RestoringLouisiana’s Coast Protecting Our People

crcl.org

Made possible by the Greater New Orleans Foundation.

crcl.org

Made possible by the Greater New Orleans Foundation.

Restoration PROTECTSOur Coastal Communities and Economy

One dot represents 100 people in the coastal zone

Louisiana ranks first in the nation in total shipping tonnage.

Louisiana accounts for 26% of the total catch in the lower 48 states.

80% of the nation’s offshore oil and gas moves through the coast.

Navigation Fisheries Oil and Gas

11. Evacuation Routes

These routes are selected to move large numbers of people to safer areas when there is an approaching storm.

2. Barrier Island

Long, narrow islands found nearby and parallel to the mainland coast, barrier islands can significantly reduce wave height and help decrease the amount of storm surge that reaches the mainland.

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1. Shelf

The transition area from the deep open ocean to the coastline, the shallow shelf can reduce the energy and height of storm-induced waves before they reach the coastline.

3. Sound

Large shallow water bodies such as sounds or bays can reduce the energy of storm surge.

4. Land Bridge

Relatively continuous areas of marsh or swamp, land bridges help reduce the movement of storm surge further inland.

6. Highway Foundation

Constructed soil foundations such as for highways, railroads, or spoil banks provide the incidental benefit of reducing storm surge.

8. Levees

Constructed levees prevent high water from reaching urban areas.

10. Elevated Buildings

Despite all the other lines of defense, there is potential for an overwhelming storm that could flood populated areas, even behind the levee protection. This is the final line of defense for people’s homes and other infrastructure.

7. Flood Gates

Closed during a flood, these structures reduce flood tides from moving up navigation channels.

9. Water Management Infrastructure

Historically, keeping water out of the urban areas behind levees has relied on pumps and canals. New alternatives to reduce flooding include: bioswales, water harvesting mechanisms, pervious paving, tree plantings, rain gardens and more.

5. Natural Ridge

The remnants of the natural levees of abandoned rivers and bayous or beach ridges, natural ridges sit higher than much of the surrounding landscape, impeding overland flow of water and helping reduce storm surge. N

atural Lines of D

efense

Engineered

Lines of D

efense

Multiple Lines of Defense StrategyThe Multiple Lines of Defense Strategy is an approach for reducing flood risks to Louisiana’s coastal communities that combines restoration and conservation of natural features found in the coastal landscape with traditional engineered protection features located closer to our cities and towns.

Created 2016. Coalition to Restore Coastal Louisiana and Louisiana State University Coastal Sustainability Studio. Multiple Lines of Defense Strategy concept by John Lopez Ph.D.

Restoration BUILDS Natural Lines of DefenseSome restoration projects mechanically move sediment from the river and offshore to rebuild Barrier Islands, Land Bridges, and Natural Ridges.

Restoration MAINTAINS Natural Lines of DefenseSome restoration projects address the conditions that lead to deterioration of important natural lines of defense. Shoreline Protection slows erosion. Hydrologic Restoration restores natural water flow. Sediment Diversions add sand, mud, and fresh water to nourish and maintain land.

Restoration SUPPORTS Engineered Lines of DefenseCoastal restoration supports the engineered lines of defense by absorbing impact from storm surge and waves. The natural lines of defense protect the engineered lines of defense from the full stress of coastal storms.

Barrier Islands

Land Bridges

Natural Ridge Restoration Hydrologic Restoration

Sediment Diversions

Shoreline ProtectionLevees

Water Management Area

Elevated Houses

Flood Gates

Evacuation Route and Highway Foundation

Created 2016. Coalition to Restore Coastal Louisiana and Louisiana State University Coastal Sustainability Studio. Multiple Lines of Defense Strategy concept by John Lopez Ph.D.

Restoration and Multiple Lines of Defense in Southeast Louisiana

Breton Sound

Continental Shelf

Chandeleur Sound

Bayou Dupont Marsh and Ridge Restoration

West Lake Boudreaux Shoreline Protection and Marsh Creation

East Grand Terre Barrier Island Restoration

Mid-Breton Sediment Diversion (proposed)

Davis PondFreshwater Diversion

Maurepas SwampFreshwater Diversion

CRCL Oyster Reef Creation Project

Restoration BUILDS Natural Lines of DefenseSome restoration projects mechanically move sediment from the river and offshore to rebuild Barrier Islands, Land Bridges, and Natural Ridges.

Restoration MAINTAINS Natural Lines of DefenseSome restoration projects address the conditions that lead to deterioration of important natural lines of defense. Shoreline Protection slows erosion. Hydrologic Restoration restores natural water flow. Sediment Diversions add sand, mud, and fresh water to nourish and maintain land.

Restoration SUPPORTS Engineered Lines of DefenseCoastal restoration supports the engineered lines of defense by absorbing impact from storm surge and waves. The natural lines of defense protect the engineered lines of defense from the full stress of coastal storms.

Barrier Islands

Land Bridges

Natural Ridge Restoration Hydrologic Restoration

Sediment Diversions

Shoreline ProtectionLevees

Water Management Area

Elevated Houses

Flood Gates

Evacuation Route and Highway Foundation

Created 2016. Coalition to Restore Coastal Louisiana and Louisiana State University Coastal Sustainability Studio. Multiple Lines of Defense Strategy concept by John Lopez Ph.D.

Restoration and Multiple Lines of Defense in Southeast Louisiana

Breton Sound

Continental Shelf

Chandeleur Sound

Bayou Dupont Marsh and Ridge Restoration

West Lake Boudreaux Shoreline Protection and Marsh Creation

East Grand Terre Barrier Island Restoration

Mid-Breton Sediment Diversion (proposed)

Davis PondFreshwater Diversion

Maurepas SwampFreshwater Diversion

CRCL Oyster Reef Creation Project