United states department of interior bureau of ocean energy management

Download 6.17 Mb.

Page	2/17
Date	01.02.2018
Size	6.17 Mb.
	#38096

1 2 3 4 5 6 7 8 9 ... 17

INTRODUCTION
1.1Purpose and Need
DESCRIPTION OF THE ACTION AND ACTION AREA

1.0 -INTRODUCTION 1

1.1Purpose and Need 2

2.0 -DESCRIPTION OF THE ACTION AND ACTION AREA 3

1.2Introduction 3

1.3Previous NEPA Documents 4

1.4Restoration Areas 4

1.4.1East Timbalier Island Restoration Area 4

1.4.2West Belle Headland Restoration Area and Feeder Beach 8

1.4.3West Belle Headland Renourishment Area 13

1.5Borrow Areas 15

1.6Sediment Pump-Out Areas and Conveyance Corridors 21

1.7General Construction Methods 27

3.0 -DESCRIPTION OF STATUS OF SPECIES 30

1.8Rufa Red Knot 31

1.8.1Description of the Species 31

1.8.2Species Habitat and Distribution 32

1.8.3Status and Cause of Decline 33

1.9Piping Plover 34

1.9.1Description of the Species 34

1.9.2Species Habitat and Distribution 34

1.9.3Status and Cause of Decline 35

1.10Atlantic Sturgeon (Gulf subspecies) 37

1.10.1Description of the Species 37

1.10.2Species Habitat and Distribution 38

1.10.3Status and Cause of Decline 39

1.11West Indian Manatee 39

1.11.1Description of the Species 39

1.11.2Species Habitat and Distribution 40

1.11.3Status and Population Trends 40

1.12Hawksbill Sea Turtle 41

1.12.1Description of the Species 41

1.12.2Species Habitat and Distribution 41

1.12.3Status and Cause of Decline 42

1.13Kemp’s Ridley Sea Turtle 42

1.13.1Description of the Species 42

1.13.2Species Habitat and Distribution 42

1.13.3Status and Cause of Decline 43

1.14Leatherback Sea Turtle 43

1.14.1Description of the Species 43

1.14.2Species Habitat and Distribution 43

1.14.3Status and Cause of Decline 44

1.15Green Sea Turtle 44

1.15.1Description of the Species 44

1.15.2Species Habitat and Distribution 44

1.15.3Status and Cause of Decline 46

1.16Loggerhead Turtle 46

1.16.1Description of the Species 46

1.16.2Species Habitat and Distribution 46

1.16.3Status and Cause of Decline 47

4.0 -ANTICIPATED EFFECTS OF THE PROPOSED RESTORATION PROJECT 49

1.17Red Knot and Piping Plover 49

1.18Atlantic Sturgeon 49

1.19West Indian Manatee 49

1.20Sea Turtles 50

1.20.1Green Sea Turtle 51

1.20.2Hawksbill Sea Turtle 51

1.20.3Kemp’s Ridley Sea Turtle 51

1.20.4Leatherback Sea Turtle 51

1.20.5Loggerhead Sea Turtle 51

1.21Proposed Conservation Measures 51

1.21.1Red Knot and Piping Plover Monitoring 51

1.21.2Nesting Shorebird Abatement for Species Protected under the Migratory Bird Treaty Act 52

1.21.3Sea Turtle Conservation Measures 53

5.0 -CONCLUSIONS 54

6.0 - LITERATURE CITED 55

List of Figures

Figure 2‑1. Project Area Map 3

Figure 2‑2. East Timbalier Island Restoration Plan View 6

Figure 2‑3. East Timbalier Island Restoration Typical Cross Section 7

Figure 2‑4. West Belle Headland Restoration Plan View 9

Figure 2‑5. West Belle Headland Restoration Typical Cross Sections 10

Figure 2‑6. West Belle Headland Renourishment and Feeder Beach 11

Figure 2‑7. West Belle Headland Feeder Beach Typical Cross Section 12

Figure 2‑8. West Belle Headland Renourishment Typical Cross Sections 14

Figure 2‑9. South Pelto Borrow Area 17

Figure 2‑10. Ship Shoal Borrow Area 18

Figure 2‑11. East Timbalier Marsh Borrow Area 19

Figure 2‑12. West Belle Headland Marsh Borrow Area 20

Figure 2‑13. East Timbalier Island Pump-Out Area 22

Figure 2‑14. West Belle Pump-Out Area and Conveyance Corridor 23

Figure 2‑15. East Timbalier Marsh Conveyance Corridor 24

Figure 3‑16. Piping Plover Critical Habitat Unit LA-5 36

List of Tables Page

Table 2‑1. Dredging Equipment Operation Considerations 26

Table 3‑2. Threatened and Endangered Species in Lafourche and Terrebonne Parish (Last Update: May 4, 2016) 30

Glossary of Terms

Term	Definition
BA	Biological Assessment
BO	Biological Opinion
BOEM	Bureau of Ocean Energy Management
BTNEP	Barataria-Terrebonne National Estuary Program
CPRA	Coastal Protection and Restoration Authority
CWPPRA	Coastal Wetlands Planning, Protection and Restoration Act
ESA	Endangered Species Act
GEFF	Geomorphic and Ecologic Form and Function
LCA	Louisiana Coastal Area
LDWF	Louisiana Department of Wildlife and Fisheries
MCY	Million Cubic Yards
MMPA	Marine Mammal Protection Act
NAVD88	North American Vertical Datum of 1988
NFWF	National Fish and Wildlife Foundation
NMFS	National Marine Fisheries Service
NOAA	National Oceanic and Atmospheric Administration
OCS	Outer Continental Shelf
SI	Silent Inspection
TBBSR	Terrebonne Basin Barrier Shoreline Restoration
USACE	U.S. Army Corps of Engineers
USFWS	U.S. Fish and Wildlife Service

INTRODUCTION

On April 20, 2010, an explosion on the Deepwater Horizon MC252 drilling platform occurred releasing an estimated five (5) million barrels of oil into the Gulf of Mexico (GOM) and adversely affecting large coastal areas of Louisiana including the TE-118 East Timbalier Restoration Project Area. The Oil Pollution Act authorizes the Natural Resource Trustees to evaluate the impacts of the Deepwater Horizon oil spill on natural resources and develop restoration plans to offset these impacts. The Gulf Environmental Benefit Fund (Gulf Fund) was established by the National Fish and Wildlife Foundation (NFWF) in accordance with plea agreements between BP Exploration & Production, Inc., Transocean Deepwater, Inc. (January 03, 2013), and the United States of America following the 2010 Deepwater Horizon disaster.

The Coastal Protection and Restoration Authority (CPRA) serves as the designated State agency for the Project, a Gulf Fund Project administered by the NFWF. This Project is one of several that the State of Louisiana has proposed for the Gulf Fund process specifically to address the impacts of the Deepwater Horizon Oil Spill on the natural resources within the Project Area. The engineering and design of the Project was authorized by NFWF in November 2013.

The purpose of this Biological Assessment (BA) is to address the effects of the TE-118 East Timbalier Island Barrier Island Restoration Project (hereinafter referred to as the Project) on species listed as endangered or threatened under the Endangered Species Act (ESA), or their designated critical habitat. Based on conducting a regional evaluation for the surroundings of East Timbalier Island, the Project comprises not only restoration at East Timbalier Island, but also restoration at the West Belle Headland. Therefore, the project involves restoring approximately 516 acres of beach, dune, and intertidal marsh habitat on East Timbalier Island and approximately 819 acres of beach, dune, and intertidal marsh on the West Belle Headland, for a combined total of 1,335 acres. The project includes offshore borrow areas for beach and dune habitat referenced as South Pelto Lease Blocks 12, 13 and 14 and Ship Shoal Lease Blocks 12 and 13. The offshore borrow area for beach and dune fill sediment is located in Federal waters under the jurisdiction of the U.S. Department of Interior, Bureau of Ocean Energy and Management (BOEM). Preliminary design cut volume estimates of suitable sediments within the South Pelto Borrow and Ship Shoal Borrow Area is approximately 4.7 and 6.5 million cubic yards (MCY), respectively. Two pump-out areas, East Timbalier Pump-Out and West Belle Pump-Out, have been delineated with an associated sediment delivery corridor to hydraulically unload via hopper dredge or scow barges. The nearshore borrow areas for marsh habitat referenced as East Timbalier Island Marsh Borrow Area and West Belle Marsh Borrow Area includes a previously permitted sediment delivery pipeline conveyance corridor to connect the marsh borrow areas to East Timbalier Island and West Belle Headland. The corridors do not require any excavation for pipeline installation, as the weighted sediment discharge pipelines will be placed directly on the sea floor.

Early coordination and pre-consultation with the US Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS) was conducted during phone conversations and meetings, including a pre-application meeting on September 14, 2016 and a meeting with the BOEM on December 20, 2016. This BA, prepared for the CPRA, addresses the proposed action in compliance with Section 7 of the ESA. Section 7 assures that, through consultation (or conferencing for proposed species) with the USFWS and the NMFS, Federal actions do not jeopardize the continued existence of any threatened, endangered or proposed species, or result in the destruction or adverse modification of critical habitat.

The following ESA-listed species potentially occur in the area: Atlantic Sturgeon (Acipenser oxyrinchus desotoi), West Indian Manatee (Trichechus manatus), Green Sea Turtle (Chelonia mydas), Hawksbill Sea Turtle (Eretmochelys impricate), Kemp’s Ridley Turtle (Lepidochelys kempii), Leatherback Sea Turtle (Dermochelys coriacea), Loggerhead Sea Turtle (Caretta caretta) and designated critical habitat, Piping Plover (Charadrius melodus) and its designated critical habitat, and Red Knot (Calidris canutus) (USFWS 2016, NMFS 2016).

1.1Purpose and Need

The specific objectives of the Project are “…restoration of dune, supratidal, and intertidal habitat on East Timbalier Island” (NFWF, undated). The Project’s overarching goals are to restore the geomorphic and ecologic form and function (GEFF) of East Timbalier Island and the West Belle Headland as a component of the Terrebonne Basin Barrier Shoreline system. The barrier system separates the 1.7 million acres of the Terrebonne and Timbalier Bays from the GOM, regulating estuarine conditions within the Barataria Terrebonne National Estuary including expansive diverse wetlands that transition from saltmarsh to freshwater marsh. Robust barrier islands are critical for this estuarine system to continue to function as productive nursery areas for numerous species of commercially- and recreationally-important fishes and invertebrates. Without such projects the barrier islands will continue to disintegrate and convert to shoals, compromising biological, physical and chemical estuarine gradients and accelerating estuarine wetland loss leading to environmental and commercial benefits.

Restoring the geomorphic form and function of the degraded barrier system involves introduction of sand to construct beach and dune habitat. In addition, it includes providing a marsh platform to capture sand that is overwashed during major storm events; serving as a “rollover” platform as the islands migrate landward. Restoration of ecologic form and function includes vegetating both the restored dunes and back-barrier marsh platforms with native plants, to provide wetland habitat for a diverse number of plant and animal species, and to help retain sediment.

DESCRIPTION OF THE ACTION AND ACTION AREA

1.2Introduction

The Project includes restoring East Timbalier Island and extending the West Belle Headland, westward from the previously constructed West Belle Pass Headland (TE-52) project site, through beach and dune fill placement utilizing offshore sand resources located in Federal waters, as well as, constructing back-barrier marsh using mixed sediment from nearshore sources located in State waters. In addition, the Project includes a Feeder Beach along West Belle Headland, westward of the West Belle Pass Jetties, which would provide sediment to nourish the shoreline, as well a re-nourishment component at the site of the previously completed TE-52 project. See Figure 2-1 for an overview of the Project features.

Figure 2‑1. Project Area Map

The purpose of the feeder beach is to introduce sediment at the updrift end of the area intended to receive the fill. Then, the longshore transport distributes the fill to the rest of the project area. Feeder beaches work best in areas that serve as a source of littoral material for downdrift beaches, in areas that are presently experiencing a deficit in the supply of littoral material and have unusually high loss rates, and in areas where the net longshore transport direction is predictable and the net transport rate is "strong" (i.e., longshore sand transport in one direction greatly exceeds the transport in the other direction) (USACE, 2008).

The construction duration for the Project, including any work conducted on West Belle Headland, is 27 months. This includes sand fence installation which will be installed as dune segments are completed and accepted. Vegetative plantings will be a separate contract and will be installed after construction during fall through early spring pending final completion, out of bird nesting season. While the base bid and primary work is East Timbalier, the contractor could begin work at West Belle Headland simultaneously or sequentially within the construction period.

Directory: East%20Timbalier

Download 6.17 Mb.

Share with your friends:

1 2 3 4 5 6 7 8 9 ... 17