Attachment_4_Appendix_B_North_Breton_Island_Phase_3_Planting_Restoration_Plan.docx

ATTACHMENT A

RESTORATION PLAN

North Breton Island Restoration Project – Phase 3 Planting and Sand Fence Installation

1. INTRODUCTION:

North Breton Island is an approximately 422-acre barrier island located approximately 62 miles southeast from the metropolitan city of New Orleans, Louisiana (LA). The island is within the southern portion of Breton NWR in Plaquemines Parish, LA. North Breton Island provides breeding habitat for colonies of nesting wading birds and seabirds, as well as wintering habitat for shorebirds and waterfowl.

In 2010, the Deepwater Horizon oil spill caused ecosystem level damages to barrier island habitat and bird populations on the Gulf coast. As part of the Deepwater Horizon Oil Spill Natural Resource Damage Assessment and Restoration (NRDAR) program, the Department of the Interior (DOI), through the U.S. Fish and Wildlife Service (Service) was tasked with mitigating environmental damages caused by the spill. North Breton Island was identified as an ideal location to provide additional bird nesting habitat to help restore bird populations that were injured by the spill. The primary objective of the North Breton Island Restoration Project is to restore beach, dune, and back barrier marsh bird habitat on the island.

This Restoration Plan outlines the objectives for a Phase 3 native vegetation planting at North Breton Island and the installation of supplemental or replacement sand fencing.

2. RESTORATION AND ENHANCEMENT ACTIVITIES:

2.1 Overview:

The plantings at North Breton Island under the Phase 3 Planting effort will be split between two Restoration Areas (See Figure 1). The two Restoration Areas are as follows:

1. Avicennia germinans (Black mangrove) Restoration Area

2. Spartina alterniflora (Smooth cordgrass) Restoration Area Each Restoration Area will be planted using different species and with spacing as outlined in this document and in the Technical Specifications of the “North Breton Island Restoration Project – Phase 3 Planting and Sand Fence Installation” Performance Work Statement.

Figure 1. Restoration areas.

2.2 Avicennia germinans Restoration Area

Within the Avicennia germinans Restoration Area, only Avicennia germinans will be planted. It will be planted throughout the entirety of the Restoration Area using a 3ft-by-3ft grid as shown in Figure 2.

Figure 2. Avicennia germinans spacing diagram.

2.3 Spartina alterniflora Restoration Area

Within the Spartina alterniflora Restoration Area, only Spartina alterniflora will be planted. It will be planted throughout the entirety of the Restoration Area using a 3ft-by-3ft grid as shown in Figure 3.

Figure 3. Spartina alterniflora spacing diagram.

2.4 Sand Fencing

Along the center of the island runs an approximately 15,000 linear foot (LF) dune crest. Between 2020 and 2022 fill was placed on the island to increase its elevation and area. After fill was placed, sand fencing was installed along the dune crest to ensure the stability and continued growth of the created dunes (see Figure 4). Since then, portions of the sand fencing have degraded or been completely buried by sand. As such, the Government wants to supplement the previously installed dune fencing with additional rows of sand fencing at targeted areas with the intent to install between 6,120 LF and 7,500 LF in total.

The newly installed fencing will fall adjacent to or near the already existing fencing or dune crest. Runs of sand fencing will be at most 450 LF. Where runs of fencing are placed adjacent to each other, or next to existing fencing, there should be a 30ft overlap between a run of fencing and any adjacent run of fencing (See Figure 5). Throughout the 30ft overlap there should be an approximately 3ft gap of distance between the two runs of sand fencing, except every 5th overlap should have an 8ft gap. The 8ft gap is to allow transit of vehicles and other equipment when necessary. Because conditions on the island may change between the time of drafting this restoration plan and implementation, the final location and orientation of sand fencing will be completed at least 60 days prior to the Contractor’s scheduled date for mobilization to the island.

Figure 4. Existing sand fencing.

Figure 5. Supplemental sand fencing diagram.

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