LAKE HERMITAGE MARSH CREATION BA-42 FINAL (95%) DESIGN REVIEW MEETING NOVEMBER 3, 2008

BA-42 PROJECT BACKGROUND Nominated by the FWS in February 2005 at the Region 2 RPT meeting Selected by CWPPRA Technical Committee as PPL15 Candidate in March 2005 Approved for Phase 1 funding by CWPPRA Task Force in November 2005 Project Kickoff Meeting and Field Trip conducted in June 2006

BA-42 PROJECT AREA MARSH LOSS From 1932 to 1990, the Lake Hermitage Basin (between Miss. River and Bayou Grande Cheniere) lost 38% of its marsh An additional 28% is expected to be lost by 2050 Causes of marsh loss include subsidence, sediment deprivation, shoreline erosion, and altered hydrology due to the high degree of oil and gas exploration southeast of Lake Hermitage Eastern lake rim has deteriorated considerably; loss rates as high as 34ft/yr have been measured

BA-42 PROJECT PURPOSE Goals – Restore marsh habitat south and southeast of Lake Hermitage. Restore an elevated lake rim along the eastern Lake Hermitage shoreline. Reduce fetch in open water areas. Proposed Solution - Sediment will be dredged from the Mississippi River and placed in two cells to create 534 acres of marsh. Mississippi River sediment will also be used to rebuild the eastern Lake Hermitage shoreline. In addition, 7,300 linear feet of terraces will be built and a plug installed on an oil and gas canal.

PHASE 0 PROJECT 593 acres of marsh creation 6,200 ft of rock shoreline protection plug on an oil/gas canal 25,000 linear feet of terraces

PRELIMINARY DESIGN SURVEYS GEOTECHNICAL INVESTIGATION/ANALYSIS WIND ANALYSIS HYDRAULIC ANALYSIS MARSH CREATION DESIGN EARTHEN TERRACE DESIGN SHORELINE RESTORATION DESIGN DREDGE PIPELINE TRANSPORT/CROSSING CONSTRUCTION COST ESTIMATE

PROJECT SURVEYS Fill Site Surveys Borrow Site/Mississippi River Surveys Average Marsh Elevation Surveys Geophysical Survey

Fill and Borrow Site Surveys Includes Topographic, Bathymetric, Magnetometer, and Average Marsh Elevation surveys of the proposed marsh creation cells Performed by Sigma Consultant Group, Inc during the time period of February 2, 2007 to April 12, 2007 Horizontal and Vertical Control – two existing LDNR secondary monuments.

Survey Layout

Average Marsh Elevation

Geophysical Survey Included a Geophysical Survey (Bathymetric, Magnetometer, Sub- bottom and Side-scan surveys) of the proposed Mississippi River borrow site Performed by Louisiana State University Coastal Studies Institute Verified location of existing pipelines and revealed sand throughout proposed borrow cut depth R/V Coastal Profiler

GEOTECHNICAL INVESTIGATION AND ANALYSIS 13 subsurface borings throughout the project area Analysis included: –Determination of Soil Characteristics –Slope Stability Analysis - containment dikes, terraces, shoreline protection/restoration features –Settlement Estimations - containment dikes, marsh fill, terraces, shoreline protection/restoration features –Cut:Fill Ratio Determination Eustis Engineering Services, LLC during the time period of April 12, 2007 through April 30, 2007

Locations of Borings

Slope Stability Analysis PCSTABL (Spencer’s Method)-produces global safety factor Slope Stability Recommendations: –Containment Dikes: Crown Elevation: +5.5 feet NAVD 88 Side Slope: 1(V):6(H) Crown Width: 5.0 feet Accepted Safety Factor: 1.3 –Earthen Terraces: Crown Elevation: +3.6 feet NAVD 88 Side Slope: 1(V):3(H) Crown Width: 20.0 feet Accepted Safety Factor: 1.6 –Sand Berm: Crown Elevation: +4.2 feet NAVD 88 Lakeside Side Slope: 1(V):50(H) Marshside Side Slope: 1(V):25(H) Crown Width: 50.0 feet Accepted Safety Factor: 2.1

Settlement Analysis CSETT (USACE) and SD3 (Univ of Texas): –Implementation of Boussinesq stress distribution theory Primary Goal: Determination of target marsh fill elevation –Settlement of underlying soils (compaction) –Self Weight Consolidation

Settlement Analysis

Cut:Fill Ratios Eustis Recommendations –Mechanical Dredging: 2.0:1.0 –Hydraulic Dredging: 1.25:1.0 – 1.5:1.0 Design Cut:Fill Ratios –Containment Dikes/Terraces: 2.0:1.0 –Hydraulic Dredging for Marsh Creation: 1.3:1.0 –Hydraulic Dredging for Shoreline Restoration: 2.0:1.0

WIND ANALYSIS New Orleans Naval Air Station (Alvin Calendar Field), Belle Chase,LA 90 th Percentile Wind: –Magnitude: 12 knots –Direction: 204° Clockwise from north

HYDRAULIC ANALYSIS Tidal Datum Wave Setup Wave Hindcasting Wave Transformation Wave Runup

Tidal Datum Range Ratio Method: Correlates limited gage data to gage with at least 19 years of data (tidal epoch). –Subordinate Station: LDNR gage BA04-17 (3 miles SE of project area) –Control Station: NOAA station # (Grand Isle) MHW = 0.88 ft. NAVD 88 MLW = 0.34 ft. NAVD 88

Wave Setup Setup: The change in still-water levels on a body of water caused by wind stresses on the surface of the water. –The difference in the average of the water level readings associated with the 90 th percentile wind and the MHW (1.06 ft. NAVD 88 – 0.88 ft. NAVD 88) –Setup = 0.18 ft. NAVD 88

Wave Hind Casting

Wave Transformation

Wave Runup Runup: Maximum height to which a breaking wave will run up onto the shoreline –Used to the determine the design elevation of shoreline feature to protect against waves generated by the 90th percentile wind –Simplified Calculation: Sum of the setup, mean high water level and the wave height corresponding to the design contour –Runup = Design Elevation = +2.3 ft. NAVD 88

MARSH CREATION DESIGN Fill Site Design Borrow Site Design Containment Dike Design

MARSH CREATION DESIGN Fill Site Layout: Historical Bayou

MARSH CREATION DESIGN Fill Site Layout: Dewatering/Nourishment

MARSH CREATION DESIGN Target Fill Elevation Determined from Eustis settlement curves Goal: To maintain average healthy marsh elevation (+1.2 ft. NAVD 88) throughout the 20 year project life Target Fill Elevation = +2.0 ft. NAVD 88

MARSH CREATION DESIGN Fill Volume-Sections

MARSH CREATION DESIGN Fill Volume-3D Surface

MARSH CREATION DESIGN Acreage and Fill Volumes Fill Acreage: –Fill Site A = 352 acres –Fill Site B = 182 acres Fill Volumes: –Fill Site A = 2,531,259 cubic yards –Fill Site B = 1,119,525 cubic yards *Includes filling of containment dike borrow areas

MARSH CREATION DESIGN Borrow Site Design Proximity to the Project Area Pipelines –Geophysical survey verified location of existing pipelines and did not revealed any major underwater obstructions Ideal Crossing Location Maximum Dredging Elevation Coordination with navigation entities

MARSH CREATION DESIGN Borrow Site Design-Plan View

MARSH CREATION DESIGN Borrow Site Design USACE Mississippi River Levee –All excavations must be at least 750 feet from any protection levee centerline; –Borrow sites must be outside the USACE maintained navigation channel; –Excavation in the river must not be made less than 4,000 feet upstream of a bridge crossing; –The side slopes of the borrow site must be no steeper than 1(V):5(H); –The excavation must proceed from landside to riverside limits to minimize the possibility of overburden failure of the bank; –Mississippi River Levee concrete revetment.

MARSH CREATION DESIGN Borrow Site Design-Volume Analysis Available vs Required Available Volume computed using river sections Required Volume = Fill Volume * C:F Available = 6,247,664 cubic yards Required = 5,251,841 cubic yards

MARSH CREATION DESIGN Acreage and Fill Volumes Available vs Required –Available Volume computed using river sections –Required Volume = Fill Volume * C:F –Available = 6,247,664 cubic yards –Required = 5,251,841 cubic yards

MARSH CREATION DESIGN Containment Dike Design Crown Elevation: +3.0 ft. NAVD 88 –Maintained throughout construction Side Slope: 1(V):6(H) Top Width: 5.0 ft.

EARTHEN TERRACE DESIGN Crown Elevation: +3.5 ft. NAVD 88 –Maintain an elevation of +2.3 ft. NAVD 88 through 20 year project life Side Slope: 1(V):3(H) Top Width: 10.0 ft.

EARTHEN TERRACE DESIGN Terrace Layout

SHORELINE RESTORATION DESIGN Crown Elevation: +4.0 ft. NAVD 88 –Maintain an elevation of +2.3 ft. NAVD 88 through 20 year project life Lake Side Slope: 1(V):50(H) Marsh Side Slope: 1(V):25(H) Top Width: 50.0 ft. Constructed with dredged sand –Volume = Fill * C:F –390,231 cubic yards

DREDGE PIPELINE CROSSING

CONSTRUCTION COST ESTIMATE

ESTIMATED CONSTRUCTION SCHEDULE

CWPPRA SOP and NEPA REQUIREMENTS Landrights Ecological Review Monitoring O&M Plan Permits Environmental Assessment

Landrights Pipeline ROW: –Plaquemines Parish Gov’t –Joan R. Brown, et al. –Shingle Point, LLC Marsh Creation Site: –Defelice Family Company –Bradish-Johnson Co. Ltd.

Landrights Pipelines (Marsh Creation Site): –Shell Pipeline 20” Crude –Boardwalk Pipeline 8” and 20” Crude Oyster Leases: –None

Ecological Review Based on the evaluation of available ecological, geological, and engineering information, and a review of scientific literature and similar restoration projects, the proposed strategies of the Lake Hermitage Marsh Creation project will likely achieve the desired ecological goals. Therefore, it is recommended that this project progress towards the 95% Design Review stage pending a favorable 30% Design Review.

Monitoring Plan CWPPRA projects authorized for construction after April 16,2003 will be monitored only with CRMS stations, other existing data collection, and any additional data collection funded separately from CRMS monitoring. There are no CRMS stations within the project boundary; however there are three CRMS station in the vicinity.

CRMS Stations in the Vicinity of BA-42

O & M Plan As of this time, there are no funds for O&M other than yearly on-site inspections.

Permits Pre-application meeting was held with the USACE on April 29, –Permit Analyst assigned –Multiple NOD Branch representatives present Follow-up with Navigation Stakeholders –Mississippi Maintenance Forum – June 4 –Maritime Navigation Safety Association – June 25

Environmental Assessment Work will begin on the EA after a favorable 30% Design Review Cultural Resources Evaluation meeting held with SHPO – August 12 –No cultural resource sites were identified within the project area

QUESTIONS?