Russ J. Joffrion, P.E. Whitney Thompson, P.E.

Transcription

1 A Case Study and Logistics Review on the Design and Construction of the Bayou Dupont Mississippi River Sediment Marsh Creation Project Jefferson and Plaquemines Parishes, LA Russ J. Joffrion, P.E. Whitney Thompson, P.E. Louisiana Office of Coastal Protection and Restoration 2010 Restore America s Estuary Conference, Galveston, TX

2 Outline Project background and objectives. Design requirements for a successful marsh creation project. Project Construction Challenges. Lessons Learned.

3 Project Background Funding Sources: Coastal Wetlands Planning, Protection, and Restoration Act (CWPPRA) and the American Recovery and Reinvestment Act Project Sponsors: Louisiana Office of Coastal Protection and Restoration (OCPR) Environmental Protection Agency (EPA) National Oceanic and Atmospheric Administration (NOAA)

4 Project Objectives Create and restore approximately 577 acres of intermediate marsh. Utilize the renewable resource of the Mississippi River for the marsh fill material. Provide pipeline corridor infrastructure crossings for future dredging projects.

5 Project Location NEW ORLEANS PROJECT AREA

6 Project Location NEW ORLEANS PROJECT AREA

7 Barataria Basin Landbridge Naomi Lafitte Lake Salvador The Pen BA-41 (Awarded?) BA-39 (II) (Built) BA-39 (Built) BA-39 (III) EPA Myrtle Grove BA-23 (Built) BA-26 (Built) R2-BA-12 NRCS PPL 20 BA-48 BA-48 (II) NOAA PPL 20 BA-27 (Built) BA-36 (Built) 20.1 BARATARIA LANDBRIDGE R2-BA-15 NRCS PPL 20 Little Lake Turtle Bay

8 Criteria Needed for a Successful Marsh Creation Project Identify Infrastructure & Cultural Resources Identify the Borrow Source Identify Marsh Creation Fill Area(s) Identify Construction Access & Pipeline Corridors Bathymetric and Geotechnical Data Acquisition Determine Target Marsh Fill Elevation Submit Permits

9 Project Location

10 Mississippi River Borrow Area Design Criteria USACE Mississippi River Dredging Restrictions and offsets Navigation Concerns Existing Revetment Mississippi River Levee Crossing Requirements River Stage Seasonal Variation Required Volume for Marsh Fill Areas Proposed USACE Saltwater Barrier Sill Location Monitoring Bathymetric Surveys for Infilling

11 Revised Mississippi River Borrow Area

12 Revised Mississippi River Borrow Area Material: D50 is approximately 0.35mm & 10% silt. Located on a stable point bar. Revised Mississippi River Borrow Area Template due to navigation concerns; conducted slope stability analyses.

13 Marsh Creation Design Criteria Existing Marsh Elevation = 0.88 NAVD88 Mean High Water = 0.87 NAVD88 Mean Low Water = 0.50 NAVD88 Target Marsh Fill Elevation = 1.3 NAVD88 Construction Marsh Fill Elevation = 2.0 NAVD88 (based on consolidation estimates)

14

15 Marsh Creation Fill Areas

16 Marsh Creation Area- Increment 2

17 Dredge Pipeline Corridor

18 Dredge Pipeline Corridor Highway Crossing Railroad Crossing

19 Construction Bid Opening November Great Lake Dredge and Docks Company BA-39: $20,723,015 BA-39 II: $ 4,566,003 Notice to Proceed February 2009 Construction Start April 2009 Dredging Complete March 2010 Demobilization Complete April 2010

20 Construction Equipment 32 Hydraulic Cutter Suction Dredge Florida. Approximately 2,500,000 cubic yards river sediment placed. Marsh Hoe 1.75 cu. yd. bucket.

21 Hydraulic Dredge

22 Dredge Pipeline Corridor

23 Dredge Pipeline Corridor

24 Jacking Pit

25 Receiving Pit

26 Dewatering Equipment

27

28

29

30 Marsh Construction

31 Marsh Construction

32

33

34

35 Marsh Construction August 2010

36 August 2010

37

38

39

40 Construction Issues and Lessons Learned Mississippi River- Barge Oil Spill August High River Stage No excavation above +11 NGVD at Carrollton Gage (USACE New Orleans) Unclear Army 404 Permit Conditions Navigation Industry Borrow Area Relocation Survey Data

41 Construction Issues and Lessons Learned River Stage Fall 2009 High Water Stage

42 Acknowledgements Whitney Thompson, P.E., Coastal Planning & Engineering, Inc. Brad Miller, OCPR Project Manager Peter Hopkins, P.E., OCPR Field Engineer Paul Kaspar, EPA Project Manager Cecilia Linder & Cheryl Brodnax, NOAA Roy Woods, Project Manager, Great Lakes Dredge and Dock Company

43 Questions?