Bayou Bonfouca Marsh Creation

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The marsh in this area was fairly stable prior to Hurricane
Katrina in August 2005. There was extensive damage to the
marsh along the north shore of Lake Pontchartrain and
especially localized in the marshes near Bayou Bonfouca
when the storm surge removed many acres of marsh. Marsh
loss rates should increase in the marsh surrounding these
newly created open water areas due to an increase in wind
driven fetch. Within the project area, the Lake Pontchartrain
shoreline erosion rates seem to be very low. Currently, there
is one large breach and several smaller ones in the Lake
Pontchartrain shoreline, with many more breaches seemingly
imminent. These breaches provide direct connection between
the fresher interior marshes and higher saline waters of Lake
Pontchartrain. The breaches in the bankline should be filled
before they grow to become a major exchange point causing
an increase in interior loss rates.

The primary goal of the project is to create 533 acres and
nourish 42 acres of low salinity brackish marsh in open
water areas adjacent to Bayou Bonfouca with sediment
pumped from Lake Pontchartrain.
This project would consist of placing sediment, hydraulically
dredged from Lake Pontchartrain, in open water sites to a
height of +1.2 NAVD 88 to create 458 acres and nourish
approximately 133 acres of marsh. Several historic marsh
ponds have been identified and would be restored. Tidal
creeks are also proposed to connect these ponds to facilitate
water exchange and fisheries access. Containment dikes
would be sufficiently gapped or degraded to allow for
fisheries access no later than three years post construction.

The project would result in approximately 424 net acres of
intermediate marsh over the 20-year project life.

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This project is located in Region 1, Pontchartrain Basin, St.
Tammany Parish. Parts of the project are located within Big
Branch Marsh National Wildlife Refuge adjacent to Bayou
Bonfouca.

This project is on Project Priority List (PPL) 20.

The Bayou Bonfouca Marsh Creation project sponsors include:

Keep up with this project and other CWPPRA projects on the project page.

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Kelso Bayou Marsh Creation

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The most significant environmental problem affecting the
marshes in this area is deterioration and conversion to open
water. Marsh loss has and continues to occur as a result
of salt water intrusion and sediment export (erosion). The
construction of the Calcasieu Ship Channel and the Gulf
Intracoastal Waterway greatly increased the efficiency
of water exchange through Calcasieu Pass. Freshwater
retention was consequently reduced and salt water is able
to enter interior marshes and penetrate further north and
west. Project-area marshes are connected to the navigation
channels through a network of canals and bayous including
Kelso Bayou and Alkali Ditch. Unvegetated substrate
is vulnerable to increased tidal exchange and immense
quantities of organic substrate are being exported.
Recent marsh loss and scouring at the mouth of Kelso
Bayou from impacts related to Hurricanes Rita and Ike allow
increased salt water intrusion, tidal exchange, and storm
surge impacts.

The goal of this project is to restore and protect
approximately 319 acres of critically important marsh
and the numerous functions provided by those areas. The
proposed project will restore a portion of the historic
meandering channel of Kelso Bayou and provide direct
protection to Louisiana State Highway 27, the region’s only
northward hurricane evacuation route. Project features
include creating/nourishing 319 acres of marsh, 3,200 linear
feet of shoreline protection, and rock armor at the mouth of
Kelso Bayou to prevent additional tidal scour.

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This project is located in Region 4, Calcasieu-Sabine Basin,
Cameron Parish. The project features are located in an area
south of the Gulf Intracoastal Waterway and just west of the
Calcasieu Ship Channel.

This project is on Project Priority List (PPL) 20.

The Kelso Bayou Marsh Creation project sponsors include:

Keep up with this project and other CWPPRA projects on the project page. 

American Eagle Day

National American Eagle Day is observed each year on June 20th. This day is celebrated in honor of our national symbol, to raise awareness for protecting the bald eagle, to assist in the recovery of their habitat, and to educate Americans on their significance. The bald eagle can be sighted during its breeding season at nearly any wetland habitat such as seacoasts, rivers, large lakes, or marshes. You can find these eagles around large bodies of open water with an abundance of fish.

In the mid 20th century, America’s precious eagles were almost lost due to the effects of habitat destruction, poaching, and environmental negligence, specifically the contamination of food sources by the pesticide DDT. Thanks to conservation efforts of various organizations, conservationists, and protection laws – the bald eagle populations recovered. Habitats restored through CWPPRA projects aided in the delisting of our national symbol from the endangered species list in 2007. CWPPRA has protected, created, or restored approximately 97,177 acres of Louisiana’s vanishing coastal wetlands in its first 25 years. Those restored swamps, marshes, barrier islands/headlands, and associated open-water habitats provide foraging, nesting, breeding, wintering, escape cover, and nursery habitat for wildlife, in particular the American bald eagle.

Terracing

CWPPRA Restoration Technique: Terracing

The goal of building terraces is to achieve some of the same objectives as full marsh creation but over a larger area of open water, where marsh creation alone is not feasible. Terraces are long, earthen berms that are built by mechanically dredging material and piling and shaping the material to a desired height. Most terraces average around 3 feet tall, with shallow side slopes and a wide base. This size and shape optimize the amount of terrace that falls in the intertidal zone and will support wetland vegetation.

The objectives of constructing terraces are several and depend upon the location in which they are built. These include acting as a sediment trap to help build new land, reducing wave fetch and erosion on adjacent marsh shorelines, creating habitat for fish and waterfowl, and improving water quality to promote the growth of aquatic vegetation. Terracing projects constructed under CWPPRA have achieved each of these goals, with sediment trapping being most evident near the openings of sediment-laden bays or navigational waterways.

Terracing has become a widely used technique that is expanding across the Gulf Coast because of the success and cost-effectiveness demonstrated through CWPPRA and privately funded projects. Although these features may not look like natural marsh and often use geometric configurations, they are able to perform a lot of the functions of natural marsh in areas that have become vast open water. Developing this cost-effective technique for use in areas that have few other restoration options is a testament to CWPPRA’s ability to adapt to funding constraints and a quickly changing environment.

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TV-12 Little Vermilion Bay Sediment Trapping

 

 

 

 

Barrier Island Restoration

CWPPRA Restoration Technique: Barrier Islands

Barrier islands are known as coastal Louisiana’s first line of defense against destructive storm surge. These islands are a unique composite of beach, dune, marsh, and sand flats that host a tremendous variety of fisheries and wildlife, including endangered species. Barrier island restoration projects are designed to protect and restore the features unique to Louisiana’s barrier island chains. This type of project may incorporate a variety of restoration techniques, such as the placement of dredged material to increase island height and width, the placement of structures to protect the island from erosive forces, and the placement of sand-trapping fences, used in conjunction with vegetative plantings, to build and stabilize sand dunes.

Responsible for the majority of Louisiana barrier island restorations to date, CWPPRA has led the charge in barrier island restoration because it recognizes the ecological importance of barrier islands and their critical role in the defense of coastal Louisiana.

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BA-38 Barataria Barrier Island Complex Project: Pelican Island and Pass La Mer to Chaland Pass Restoration

 

Bayou LaLoutre Ridge Restoration and Marsh Creation

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Historic and current ridge habitat loss occurs in the form of subsidence and shoreline erosion along Bayou La Loutre. The shoreline erosion is caused by increased boat traffic diverted due to the closure of the MRGO channel. Ridge habitat consists of Live Oak Hackberry Maritime forest which is utilized by trans-gulf migratory bird species as a first and last stop when crossing the Gulf of Mexico. This critical habitat is rated as S1-Most Critically Imperiled (State Natural Heritage Program) and S2 priority by the state of Louisiana. Interior marsh loss along Lena Lagoon is caused by subsidence, sediment deprivation, increased wave fetch and construction of access and navigational canals. The integrity of the Lena Lagoon shoreline has been breached, and loss of this wetland buffer will expose the La Loutre ridge to highly erosional winter storm events.

The goal of the project is to create an approximately 31.7 acre ridge feature with material from bucket dredging Bayou La Loutre. Additionally dredged material from Lake Borgne will create 163 acres of marsh and nourish approximately 258 acres of marsh along Lena Lagoon (421 acres total).

The proposed project will create approximately 5.46 miles (28,855 ft) of ridge along Bayou La Loutre and 24.4 acres of Live Oak/Hackberry Maritime forest habitat. The ridge habitat will be built centerline along the bank of the bayou. The structure will have a +4 elevation with a 5:1 slope on the bayou side and 3:1 slope on the marsh side. Additionally the newly created ridge will include herbaceous and woody plantings with smooth cord plantings along the toe. The Lena Lagoon site will create and nourish approximately 421 acres of marsh using sediment dredged from Lake Borgne. Lena Lagoon will have a semi-confined south and east flank and a fully confined north flank. Containment will be degraded as necessary to re-establish hydrologic connectivity with adjacent wetlands.

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This project is located in Region 1, Lake Pontchartrain Basin and Breton Basin, St. Bernard Parish.

This project was approved for Phase I Engineering and Design in January 2017 and is on Priority Project List (PPL) 26.

The Bayou LaLoutre Ridge Restoration and Marsh Creation project sponsors include:

Keep up with this project and other CWPPRA projects on the project page.

 

 

Shoreline Protection

CWPPRA Restoration Technique: Shoreline Protection

Louisiana’s shorelines are eroding at a drastic pace, some at rates up to 50 feet per year. The fertile but fragile soils found in the wetlands are susceptible to wave energy. As land is lost, water bodies merge together, which can increase wave fetch and shoreline erosion. Behind these shorelines lie communities, highways, and infrastructure that are at risk of washing away.

Various techniques to defend the coastline have been tested and applied under CWPPRA. Rock revetments, oyster reefs, concrete panels, and other fabricated materials have been constructed along otherwise unstable shorelines to abate wave energy and reduce erosion. These structures are designed to break waves, and they often trap waterborne sediments behind the structures that, over time, can become new land.

Through the course of the CWPPRA program, advancements have been made in shoreline structures that have helped maintain natural processes while providing critical protection. Such advancements have included using lighter-weight materials that require less maintenance and can be constructed on organic sediments. Other advancements include low-relief structures that are designed to trap sediments and natural breakwaters such as reefs that can self-maintain and support other ecological functions. Other natural shoreline protection measures include vegetative plantings, whose roots help secure soils and can promote accretion. These projects are implemented with consideration for minimizing impacts to the surrounding environment. Although some shoreline structures may look foreign in a natural landscape, they are necessary features that physically protect communities and hold wetlands in place by mitigating the harsh forces that move to destroy them.

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BA-26 Barataria Bay Waterway East Side Shoreline Protection