St. Catherine Island Marsh Creation & Shoreline Protection

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The landfall of Hurricane Katrina in southeast Louisiana destroyed thousands of acres of marsh and other coastal habitats in the Lake Pontchartrain basin. The hurricane weakened the Lake Pontchartrain shoreline and large areas of interior marsh habitat were either lost or damaged near Chef Menteur Pass. This area has an estimated erosion rate of 18 ft./yr. or greater. A portion of the lakeshore is protected by rock dikes (Bayou Chevee PO-22, State only project and FWS funded project). Shorelines that are not protected by rock dikes will erode back into the shallow open water areas located near the shorelines further increasing erosion rates.

This project would extend the Bayou Chevee (PO-22) rock dike along approximately 33,324 LF of weakened Lake Pontchartrain shoreline. A 6,468 LF foreshore dike and a 13,851 LF revetment totaling 20,319 LF is proposed to be built along a portion of the Bayou Savauge NWR. This would protect approximately 201 acres. This project would also create/nourish 115 acres (100 acres of marsh creation and 15 acres of marsh nourisment). That marsh would be created by filling those sites with material hydraulically dredged from the bottom of Lake Pontchartrain. A combination of healthy established marshes, bayou ridges, and constructed earthen dikes would contain that material. All constructed containment dikes would be sufficiently gapped within 3 years to allow for exchange of nutrients and estuarine organisms. This project would work synergistically with other restoration projects in the area including CWPPRA, state, and Bayou Savauge National Wildlife Refuge projects.

The goals of the project are to 1) stop shoreline erosion due
to wind generated waves along 33,324 linear feet of the Lake Pontchartrain shoreline, preserving 201 acres (166 acres of marsh and 35 acres of shallow water) and 2) create/nourish 115 acres (create 100 acres of marsh and nourish 15 acres of marsh) landward of that shoreline protection.

Service goals include the protection/creation of habitat or improvement of habitat for species of concern (LDWF), priority species (JV), and threatened and endangered species (FWS). The creation of low salinity brackish intertidal marsh habitat would be beneficial to several species that are currently on these lists, including, but not limited to Black Rail, Mottled Duck, Brown Pelican, King Rail, and Saltwater Topminnow. Helping to improve habitat, especially on Federal and State owned lands, ensures the protection of those valuable resources in perpetuity and should be a priority.

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This project is located in Region 1, Pontchartrain Basin, Orleans Parish.

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

The St. Catherine Island Marsh Creation & Shoreline Protection project sponsors include:

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

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

 

Marsh Creation

CWPPRA Restoration Technique: Marsh Creation

Marsh creation replicates the natural land-building process of the Mississippi River in a controlled, and much accelerated, fashion. Land is built by a pipeline dredge that removes sediment from a “borrow” site by using a specialized vessel outfitted with a drill, suction pump, and pipe. As the drill, or cutterhead, spins, it agitates sediment at the bottom of the borrow site. This sediment is then pumped with water into a pipe that carries the resultant slurry to the restoration site. Once the slurry is in place, the water runs off as the sediment settles to form new land. Native vegetation is then installed to jump-start wetland productivity. Marsh creation projects result in restored wetlands in areas that were open water just weeks before.

CWPPRA is striving to identify and construct projects that provide strategic benefits by holding together larger ecosystems and that use renewable sediment resources like the river. Over the course of 26 years, CWPPRA has been restoring one piece of broken marsh at a time, which cumulatively yields significant results over time. The long-term vision is to sustain these restored marshes by restoring part of the riverine processes that first built them.

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PO-104 Bayou Bonfouca Marsh Creation Project

 

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

 

Bayou Decade Ridge and Marsh Creation

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The Terrebonne Basin is an abandoned delta complex, characterized by a thick section of unconsolidated sediments that are undergoing dewatering and compaction, contributing to high subsidence, and a network of old distributary ridges extending southward from Houma. Historically, subsidence and numerous oil and gas canals and pipelines in the area have contributed significantly to wetland losses. Since 1932, the Terrebonne Basin has lost approximately 20% of its wetlands. Current loss rates range from approximately 4,500 to 6,500 acres/year. This loss amounts to about130,000 acres over the next 20 years. One-third of the Terrebonne Basin’s remaining wetlands would be lost to open water by the year 2040. The wetland loss rate in the area is -0.79%/year based on USGS data from 1984 to 2016.

The proposed project’s primary feature is to create and/
or nourish approximately 504 acres of intermediate marsh adjacent to Lake De Cade and restore 11,726 linear feet of ridge habitat along the northern bank of Bayou De Cade. To achieve this, sediment will be hydraulically pumped from a borrow source in Lake De Cade. The borrow area in Lake De Cade would be located and designed in a manner to avoid and minimize environmental impacts (e.g., to submerged aquatic vegetation and water quality) to the maximum extent practicable. Containment dikes will be constructed around the marsh creation area to retain sediment during pumping. No later than three years post construction, the containment dikes will be degraded and/or gapped. Additionally, the newly constructed marsh will be planted after construction to stabilize the platform and reduce time for full vegetation. It is anticipated that material for the ridge feature will be mechanically dredged from adjacent areas within Bayou De Cade and/or the marsh area and lifted to a crown elevation of +5.0 feet, 25 feet wide, and will be planted.

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This project is located in Region 3, Terrebonne Basin, Terrebonne Parish, Lake Mechant Mapping Unit.

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

The Bayou Decade Ridge and Marsh Creation project sponsors include:

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

Wetland Plants

Plants are a vital piece of healthy and sustainable wetland ecosystems. Plants are the base of the food chain and can build new layers of organic material on top of wetlands which helps them keep pace with subsidence and rising waters. Wetland vegetation reduces erosion primarily by dampening and absorbing wave and current energy and by binding and stabilizing the soil with roots. Coastal wetland plant species are indicators of soil and hydrologic conditions. The amount and salinity of water in an area influence which plants grow there. Scientists often classify Louisiana marshes into four types: fresh, intermediate, brackish, and saline.

The Coastal Wetlands Planning, Protection, and Restoration Act puts native wetland plant benefits to use through restoration techniques that include vegetative plantings. Vegetative planting projects are used both alone and in conjunction with barrier island restoration, marsh creation, shoreline protection, and sediment and nutrient trapping restoration techniques. These projects use flood-and salt-tolerant native marsh plants that will hold sediments together and stabilize the soil with their roots as they become established in a new area.

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

 

 

 

 

Talking Wetland Habitat and Wildlife with ESA Students

Environmental Studies students in Christina Hidalgo’s class at the Episcopal School of Acadiana do more than learn about general environmental issues; they also get outside and participate in direct monitoring of the ecosystems around them. On February 21st and 23rd they were joined by Coastal Wetlands Planning, Protection, and Restoration Act staff to discuss coastal habitats, the mammal species that call them home, and different wildlife monitoring techniques.

On Tuesday CWPPRA staff and ESA students discussed the importance of barrier beach systems for both human and wildlife communities, and students were given training in how researchers trap small mammal populations in those locations for monitoring. After students deployed small mammal traps around the ESA Cade campus on Wednesday, CWPPRA staff returned Thursday morning to help with trap collection and see what students had captured. In addition to trapping a variety of insects drawn to the oatmeal-soybean bait and several traps which had been moved by larger animals, ESA students successfully captured a marsh rice rat (Oryzomys palustris)!

These rodents are found throughout the Gulf and mid-to-south Atlantic coasts and as far inland as Illinois and Kansas. As the name suggests, marsh rice rats are generally found in wetland areas, although drier areas with dense grasses and sedges, while not ideal habitat, are also utilized. A native species in Louisiana, marsh rice rats can even be found out on barrier islands where their omnivorous diet lets them take advantage of both terrestrial food resources and items that wash ashore. The rat captured on the ESA campus was trapped near a stream and probably forages along that water body at night. Finding a marsh rice rat on a school campus is a reminder that wetland habitats come in a range of sizes and types and that we share those habitats with many different species.

Invasive species

National Invasive Species Awareness Week

Invasive species (harmful non-native species) are one of the most significant drivers of global change. Consequently, they can have substantial impacts on the economy, infrastructure, and humans. Society must address invasive species as a priority, which is exactly what National Invasive Species Awareness Week intends to do. The objective of National Invasive Species Awareness Week is to bring attention to the impacts, prevention, and management of invasive species – and all those who are working toward healthy, biodiverse ecosystems.

Wetlands provide benefits ranging from water filtration to storm surge protection; however, wetlands have become vulnerable to invasive species. Known as major contributors to wetland and coastal habitat loss, invasive species also threaten native species, including endangered species that rely exclusively on the wetlands for survival. The foreign animals that have been recognized as invasive to coastal wetlands include Asian carp, wild boar, island apple snails, and nutria. Invasive plant species include Chinese tallow, common reed, and purple loosestrife. Invasive animal and plant species have altered the health of wetlands by out-competing native species for food and natural resources, often without any natural predator or control to halt the resulting aggressive spread through an area. CWPPRA strives to protect wetlands by constructing methods to diminish the invasive threat and restore native species’ dominance and health within the wetlands.

For a full list of Invasive species in Louisiana, click here.

CWPPRA continues to raise awareness and identify solutions to protect our wetlands by implementing projects to target invasive wetland species such as the Coastwide Nutria Control Program and Louisiana Salvinia Weevil Propagation Facility.

 

 

LEEC 2017

The Louisiana Environmental Education Commission, Louisiana Department of Wildlife and Fisheries, and the Louisiana Environmental Education Association hosted the 20th Environmental Education State Symposium on February 3-4, 2017 at the Embassy Suites by Hilton in Baton Rouge, La. The theme of this year’s symposium was “protecting Louisiana’s endangered species.”

The Louisiana Environmental Education Commission (LEEC) provides environmental education news from across Louisiana, including information on environmental education programs, workshops, and grant opportunities.  The state symposium furnished opportunities for formal and non-formal environmental educators from Louisiana and surrounding states to meet and share teaching techniques as well as multiple concurrent sessions for various topics and grade levels. Keynote speaker Dr. Jessica Kastler, Coordinator of Program Development at the Gulf Coast Research Laboratory’s Marine Education Center, used individual cases of endangered species to engage the audience in explorations of the process of science while cultivating environmental stewardship. In addition to the keynote speech, presenters in 15 concurrent sessions provided lesson demonstrations, hands-on workshops, and/or exemplary programs. The Coastal Wetlands Planning, Protection, and Restoration Act Public Outreach Staff was among exhibitors with a multitude of materials to assist teachers of all grade levels in furthering their students’ knowledge in environmental education and coastal protection.