Presentation on theme: "Louisiana Coastal Area, Louisiana— Ecosystem Restoration Barrier Island Restoration, Marsh Creation, and River Diversion, Barataria Basin Feasibility Study."— Presentation transcript:
Louisiana Coastal Area, Louisiana— Ecosystem Restoration Barrier Island Restoration, Marsh Creation, and River Diversion, Barataria Basin Feasibility Study
Importance of Coastal Louisiana to Nation The Mississippi River is the lifeblood of coastal Louisiana’s industries, infrastructure, ecosystem, and cultureThe Mississippi River is the lifeblood of coastal Louisiana’s industries, infrastructure, ecosystem, and culture The Louisiana coastal area and the river greatly contribute to the Nation’s economic developmentThe Louisiana coastal area and the river greatly contribute to the Nation’s economic development Billion dollar/yr coastal fishery industryBillion dollar/yr coastal fishery industry –30% of nation’s production –More than all of Atlantic seaboard production –More than any other Gulf state Infrastructure for 17% of oil and 25% of natural gas produced in nationInfrastructure for 17% of oil and 25% of natural gas produced in nation
Importance of Coastal Louisiana to Nation Navigation projects for No. 1 Port complex in NationNavigation projects for No. 1 Port complex in Nation –400 million tons/yr –155 miles of waterways threatened by coastal erosion Hurricane protection for 2 million peopleHurricane protection for 2 million people Coastal habitat for millions of birds and animalsCoastal habitat for millions of birds and animals 70% of Nation’s migratory waterfowl of Mississippi Flyway overwinter in Louisiana coastal area70% of Nation’s migratory waterfowl of Mississippi Flyway overwinter in Louisiana coastal area World renowned for recreation – fishing, hunting, and boatingWorld renowned for recreation – fishing, hunting, and boating
Importance of Coastal Louisiana to Nation The entire Mississippi River drainage basin drains through south LouisianaThe entire Mississippi River drainage basin drains through south Louisiana –Strategic national location for the regulation of basin floodwaters using Old River Control Complex, locks, flood gates, and levee systems –Supports existence, economic growth, and prosperity of businesses located along the floodplains of the entire Mississippi River and its tributaries –With the Nation’s necessary continued use of river controls in south Louisiana, river water that is life giving to coastal areas is channeled directly to the Gulf of Mexico –This represents a continual loss of natural wetland sustenance
Louisiana Land and Water Changes
Will Be Lost Forever ??? projection adapted from LSU Natural Systems Engineering Laboratory, 1998
LOUISIANA COASTAL PLAIN Land Loss 1930's to 1990* and 2050 Projection 3,500 4,000 4,500 5,000 5,500 6, Land Remaining (thousand of acres) 1,500 square miles 1,000 square miles * after Dunbar et al. 1992
Causes of Loss: 160 million tons of sediment are delivered to the continental shelf each year. Most of this material is unavailable for marsh building processes because levees prevent overbank sedimentation.
Causes of Loss: (continued) Canal and Channel Dredging
Causes of Loss: (continued)Herbivory
Causes of Loss: (continued) Subsidence (ft/century) Low 0-1 High Intermediate after Gagliano, 1999
Year Level Rise (Inches) Causes of Loss: (continued) Relative Sea Level Rise after Wigley and Raper, 1992
By 2050 nearly 1,000 square miles of Louisiana’s wetlands, an area nearly the size of Rhode Island, will become open water. Will Be Lost Forever...
Will be lost forever...
Impending Ecosystem Collapse Funded projects will have addressed 22% of projected future marsh loss through Even with these in place, 408,000 acres of marsh and 233,500 acres of swamp will be lost. This will have major social, economic, and environmental consequences. At risk are: ~ Communities ~ Infrastructure ~ Fisheries ~ Migratory Birds ~ A Unique Culture The Coast 2050/LCA Feasibility Study would address the remaining 641,500 acres of projected wetland loss.
Available Options Abandon the coast — relocate. Put the coast on life support — rock, ring, and pump. Status quo — small-scale solutions. One comprehensive plan that addresses the causes of the problem — required to sustain our coast.
Coast 2050: Toward a Sustainable Coastal Louisiana Vision: “…to sustain a coastal ecosystem that supports the environment, economy and culture of southern Louisiana, and that contributes greatly to the economy and well- being of the nation.”
Coast 2050 Ecosystem Goals Assure vertical accretion to achieve sustainability of greatest wetland acreage practicable Maintain estuarine gradient to achieve habitat diversity Maintain exchange and interface to achieve system linkages
Ecosystem Needs Acceptable to the Public Common Ground Strategic Coastal Plan Consensus Building COAST 2050 Federal State Local PARTNERSHIP
Results of Coast 2050 Initiative Consensus-based, grass roots planning initiative for ecosystem restorationConsensus-based, grass roots planning initiative for ecosystem restoration Comprehensive plan for restoration of Louisiana’s coastal landscape by Federal, state, and parish governmentsComprehensive plan for restoration of Louisiana’s coastal landscape by Federal, state, and parish governments Identification of perceived and predicted problems facing coastal LouisianaIdentification of perceived and predicted problems facing coastal Louisiana Broad-scale restoration strategiesBroad-scale restoration strategies Basis for Louisiana Coastal Area Feasibility StudyBasis for Louisiana Coastal Area Feasibility Study
The Consensus... LAFOURCHE VERMILION TERREBONNE JEFFERSON LIVINGSTON ST. BERNARD PLAQUEMINES ORLEANS ST. MARY ASCENSION ST. TAMMANY ST. MARTIN TANGIPAHOA IBERIA ASSUMPTIONCALCASIEUCAMERON ST. JOHN THE BAPTIST ST. JAMES ST. CHARLES Approved by all Coastal Parishes Coast 2050 Plan
USACE Reconnaissance Report:USACE Reconnaissance Report: –Supports the Coast 2050 Plan –Approved for feasibility study start in May 99 LCA General Investigations study authorizationLCA General Investigations study authorization –Used existing 1967 authority –Broad latitude for study purposes –Current purpose: ecosystem restoration Project funding vehicle: Water Resources Development Act (WRDA)Project funding vehicle: Water Resources Development Act (WRDA) LCA Feasibility Study
No dollar-based benefit-cost ratio criteriaNo dollar-based benefit-cost ratio criteria –Primary Criteria: $/Habitat Unit –Additional Selection Criteria: Economic Impact estimation of economic impact as ancillary benefitsestimation of economic impact as ancillary benefits hurricane, flood control, navigationhurricane, flood control, navigation economic analysis qualified for intended useeconomic analysis qualified for intended use –Existing information updated –Ranges of costs stated Cost Effectiveness/Incremental Cost Analysis used to optimize plansCost Effectiveness/Incremental Cost Analysis used to optimize plans Barataria Basin Study Methodology for Ecosystem Restoration
LOUISIANA COASTAL AREA, LOUISIANA -- ECOSYSTEM RESTORATION REGION AND BASIN MAPS FOR LOUISIANA COASTAL AREA AUTHORITY U.S. ARMY ENGINEER DISTRICT, NEW ORLEANS, LA CORPS OF ENGINEERS August 1999 Louisiana’s Coastal Basins: Louisiana’s Coast 2050 Regions: Coastal Louisiana Hydrologic Basin Area
COAST 2050 REGION 2 REGIONAL ECOSYSTEM STRATEGIES Bayou Lafourche Restore/Maintain Barrier Shoreline Restore Swamps Small River Diversions Manage Diversion Outfall Flood Protection Restore Natural Drainage Patterns Preserve Land Bridge River Diversions Maintain Shoreline Integrity Dedicated Dredging Rebuild Little Lake Marshes Conveyance Channel and Delta Lobe Sediment Trap for Marsh Creation Build and Maintain Delta Splays Prevent loss of sediments off of the Continental Shelf Extend Barrier Shoreline Protect Bay Fringe Marshes Interior Breakwaters Reef Zones Divert through Existing Locks Manage Outfall of Existing Diversions Enrich Existing Diversions with Sediment LEGEND Improve Drainage Mississippi River Diversions with Outfall Management Marsh creation with dredged material Marsh Creation along Hwy 1 and Caminada Bay
Approach for Barataria Study 18-mo. interim report 18-mo. interim report Focus -- critical, fragile gulf perimeter:Focus -- critical, fragile gulf perimeter: –Marsh creation –Barrier island restoration –River diversion Objectives:Objectives: –Rebuild and protect unique gulf fringe, bays, and shoreline ecosystem –Provide support to basin interior for restoration Preparation for envisioned 3-yr study during 18-mo. interim report: Preparation for envisioned 3-yr study during 18-mo. interim report: Hydrologic and Hydraulic modeling developed for basinHydrologic and Hydraulic modeling developed for basin Objective:Objective: –Prepare to evaluate interior basin strategies related to movement and circulation of water, sediment, and nutrients
Marsh Creation Barrier Island Restoration LOUISIANA COASTAL AREA, LOUISIANA -- ECOSYSTEM RESTORATION Barrier Island Restoration, Marsh Creation, River Diversion, and Ecosystem Restoration, Barataria Basin MARSH CREATION, BARRIER ISLAND, & RIVER DIVERSION RESTORATION AREA MAP U.S. ARMY ENGINEER DISTRICT, NEW ORLEANS, LA CORPS OF ENGINEERS August 1999 Land Loss 1930’S to to to to 1990 R2-22. Restore/maintain Barrier Shoreline, Port Fourchon to Sandy Point R2-16. Dedicated Dredging for Marsh Creation along Hwy. 1 R2-17. Dedicated Delivery of Sediment for Marsh Building in Caminada Bay R2-11. Delta Building Diversion at Bastian Bay
Considerations for Investigation Marsh Creation Target areas (Hwy. 1 and Caminada Bay):Target areas (Hwy. 1 and Caminada Bay): Alternatives for investigation:Alternatives for investigation: –Dredge and fill –Terracing –Vegetative Plantings Three scales of analysis — each alternativeThree scales of analysis — each alternative
Considerations for Investigation Marsh Creation Cut-to-fill volume of available materialCut-to-fill volume of available material Supply of dredging resourcesSupply of dredging resources Coordination with Gulf Region dredging eventsCoordination with Gulf Region dredging events Environmental impact to borrow areasEnvironmental impact to borrow areas Slope stability of borrow areas, relocationsSlope stability of borrow areas, relocations Potential dredge material sources:Potential dredge material sources: –Bayou Lafourche –Interior Barataria Basin lakes –Offshore
Strategies to Meet Design Challenges: Marsh Creation Research historical estuarine features of area.Research historical estuarine features of area. Develop conceptual designs to emulate historically open water in areas.Develop conceptual designs to emulate historically open water in areas. Use combination of dredge-and-fill, terracing, and vegetative plantings.Use combination of dredge-and-fill, terracing, and vegetative plantings. Conserve available borrow resources.Conserve available borrow resources.
Considerations for Investigation Barrier Island Restoration Volume and characteristics of available materialVolume and characteristics of available material Ship ShoalShip Shoal Barataria basin ebb-tide shoalsBarataria basin ebb-tide shoals Mississippi RiverMississippi River Types of dredging systems to efficiently and effectively perform workTypes of dredging systems to efficiently and effectively perform work Availability of dredging equipmentAvailability of dredging equipment Coordination with regional dredging eventsCoordination with regional dredging events Environmental impact to borrow areasEnvironmental impact to borrow areas
Considerations for Investigation Barrier Island Restoration Adaptive Management Concept: New sand in system thru dredge-and-fillNew sand in system thru dredge-and-fill Sand will re-arrange itself over time – littoral driftSand will re-arrange itself over time – littoral drift Some sand will be lost to gulfSome sand will be lost to gulf Minimal Operation and Maintenance costs over project life (30-50 yrs)Minimal Operation and Maintenance costs over project life (30-50 yrs)
Strategies to Meet Design Challenges: Barrier Island Restoration — Port Fourchon to Sandy Point Comprehensive offshore seismic and boring programComprehensive offshore seismic and boring program –Wide swath gulfward of islands –Ship Shoal Sediment suitability analysisSediment suitability analysis Three alternatives combining measures such as:Three alternatives combining measures such as: –Dredge and place –Coastal structures (e.g., breakwaters, revetments, geotubes) Three scales for each alternativeThree scales for each alternative
Coast 2050 Strategy Delta Building Diversion at Bastian Bay
WHAT IS THE COAST 2050 PARTNERSHIP ? Coast 2050 is about planning a better future for coastal Louisiana. The public and federal, state, and parish representatives have developed a single strategic plan to sustain our estuaries, using the best science available.