Shell Beach South Marsh Creation

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The marsh boundary separating Lake Borgne and the MRGO
has undergone both interior and shoreline wetland losses due
to subsidence, impacts related to construction and use of the
MRGO (i.e., deep draft vessel traffic), and wind-driven
waves. Although much of the project area is protected from
edge erosion by shoreline protection measures, and since
2009, the MRGO has been deauthorized for deep draft
navigation and maintenance, interior wetland loss due to
subsidence continues to cause marsh fragmentation and pond
enlargement. Wetland loss rates in the project area are
estimated to be -0.60 percent a year based on USGS
analysis.

The proposed project will create and nourish 634 acres of
marsh using dredged sediment from Lake Borgne. Existing
high shorelines along Lake Borgne, remnants of previous
containment dikes and marsh edge, would be used for
containment to the extent practical. Constructed containment
dikes would be breached/gapped as needed to provide tidal
exchange after fill materials settle and consolidate. The
project would create 346 acres of marsh and nourish at least
288 acres of existing fragmented marsh. A target fill
elevation of +1.2 feet is envisioned to enhance longevity of
this land form. Additionally, 187 acres of vegetative planting
will occur within the newly created areas. Due to the
presence of existing banklines, dredged slurry overflow
could potentially be discharged immediately adjacent to the
project polygons, resulting in nourishment of additional areas.

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This project is located in Region 1, Pontchartrain Basin, South Lake Borgne Mapping
Unit, St. Bernard Parish, north bank of the Mississippi River
Gulf Outlet (MRGO) in the vicinity of Shell Beach.

This project is on Project Priority List (PPL) 24.

The Shell Beach South Marsh Creation project sponsors include:

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

World Oceans Day

Oceans are often seen as the blood of our planet. Oceans flow over nearly three-quarters of the planet, providing 97% of the Earth’s water. Not only are oceans a home to an array of marine wildlife, they create a livable environment for land-bearing organisms like humans. Even though most people do not venture far beyond the coast, the open ocean produces a massive scope of goods and services that are a fundamental part of our health, economies, and even our weather.

Marine fisheries, shipping routes, oxygen, carbon dioxide sinks, temperature, weather control, and the water cycle are all provided by the ocean and are essential to a functioning world. Ocean-based businesses contribute more than $500 billion to the world’s economy and approximately half of the world’s population resides in the coastal zone. Oceans supply food, transportation, jobs, and products that aid in keeping people warm, safe, informed, and entertained. Around 90% of all trade between countries is carried by ship. If the ocean cannot produce it, it can at least transport the goods.

Tomorrow, June 8th, people from around the world will join together in celebration to honor, help protect, and conserve the world’s oceans. The theme for this year’s World Oceans Day is “Our Oceans, Our Future.” What a suiting theme! Regardless of our distance from the ocean, our lives are still highly affected by the health of Earth’s oceans. Oceans generate most of the oxygen that we breathe, provide food for us, regulate our climate, and clean the water that we drink. Without maintaining healthy oceans, our future will be affected dramatically.

Celebrate World Oceans Day by adopting the practice of appreciating our oceans through plastic pollution prevention and cleaning the ocean of marine litter. Take care of the oceans that give so much to us in return!

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Coastwide Vegetative Planting

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The coastal restoration community has long recognized the benefits of vegetative plantings in restoration. Many marsh creation and most terracing projects require plantings to insure success. Coastal shoreline plantings have also proven to be very effective and some have demonstrated the ability to not only stop shoreline erosion but to facilitate accretion, the process of increasing sediments. Recent hurricane events have exposed a need to have a mechanism in place where large-scale planting efforts can be deployed in a timely manner to specifically targeted areas of need, anywhere along the coast. Although the CWPPRA program can fund specific large-scale planting projects, the normal program cycle for individual projects can delay needed restoration plantings for a number of years.

The goals of this project are to facilitate a consistent and responsive planting effort in coastal Louisiana that is flexible enough to routinely plant on a large scale and be able to rapidly respond to critical areas of need following storm or other damaging events. This project set up an advisory panel consisting of representatives from various state and federal agencies who would assist in the selection of projects for funding. The project also set up a mechanism by which project nominations would be submitted for consideration. The equivalent of 90 acres of interior marsh and 40,000 linear feet of coastal shoreline will be planted per year over a 10 year period to effectively create/protect a total of 779 net acres of marsh over the 20-year project life.

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The project features are located in the coastal zone of Louisiana.

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

The Coastwide Vegetative Planting project sponsors include:

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

 

LaBranche Central Marsh Creation

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Dredging of access/flotation canals for construction of I-10 resulted in increased salinity & altered hydrology that exacerbated conversion of wetland vegetation into shallow open water bodies. Land loss is estimated to be -0.543 percent/year based on USGS data from 1984 to 2011 within the extended project boundary.

The primary goal is to restore marsh that converted to shallow open water. Project implementation will result in an increase of fisheries and wildlife habitat, acreage, and diversity along with improving water quality. The proposed project will provide a protective wetland buffer to the railroad and I-10, the region’s primary westward hurricane evacuation route, and complement hurricane protection measures in the area.

The proposed solution consists of the creation of 762 acres of emergent wetlands and the nourishment of 140 acres of existing wetlands using dedicated dredging from Lake Pontchartrain. The marsh creation area will have a target elevation the same as average healthy marsh. It is proposed to place the dredge material in the target area with the use of retention dikes along the edge of the project area. If degradation of the containment dikes has not occurred naturally by Target Year 3, gapping of the dikes will be mechanically performed. Successful wetland restoration in the immediate area (PO-17 constructed in 1994) clearly demonstrates the ability for these wetlands to be restored using material from a sustainable borrow area (outlet end of Bonnet Carre Spillway). Engineering monitoring surveys of the marsh creation area and borrow area are planned as well.

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This project is located in the Pontchartrain Basin (Region 1), St. Charles Parish. It is bounded to the north by the railroad running parallel to I-10, to the west by the marsh fringe just east of Bayou LaBranche, to the south by Bayou Traverse and to the east by marsh fringe west of a pipeline canal.

This project is on Priority Project List (PPL) 21.

The LaBranche Central Marsh Creation project sponsors include:

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

Coastwide Reference Monitoring System

In 1990, the U.S. Congress enacted the Coastal Wetlands Planning, Protection and Restoration Act (CWPPRA) in response to the growing awareness of Louisiana’s land loss
crisis. CWPPRA was the first federal, statutorily mandated program with a stable source of funds dedicated exclusively to the short- and long-term restoration of the coastal wetlands of Louisiana. Between 1990 and 2016, 108 restoration projects were constructed through the CWPPRA program. These projects include diversions of freshwater and sediments to improve marsh vegetation; dredged material placement for marsh creation; shoreline protection; sediment and nutrient trapping; hydrologic restoration through outfall, marsh, and delta management; and vegetation planting on barrier islands.

The coastal protection and restoration efforts implemented through numerous CWPPRA crms_wetlandsprojects require monitoring and evaluation of project effectiveness. There is also a need to assess the cumulative effects of all projects to achieve a sustainable coastal environment. In 2003, the Louisiana Office of Coastal Protection and Restoration (now CPRA) and the U.S. Geological Survey (USGS) received approval from the CWPPRA Task Force to implement the Coastwide Reference Monitoring System (CRMS) as a mechanism to monitor and evaluate the effectiveness of CWPPRA projects at the project, region, and coastwide levels (Steyer and others, 2003). The CRMS network is currently funded through CWPPRA and provides data for a variety of user groups, including resource managers, academics, landowners, and researchers.

The effectiveness of a traditional monitoring approach using paired treatment and reference sites is limited in coastal Louisiana because of difficulty in finding comparable test sites; therefore, a multiple reference approach using aspects of hydrogeomorphic functional assessments and probabilistic sampling was adapted into the CRMS design. The CRMS approach gathers information from a suite of sites that encompass a range of ecological conditions across the coast. Trajectories of changing conditions within the reference sites can then be compared with trajectories of change within project sites. The CRMS design not only allows for monitoring and evaluating the effectiveness of each project but will also support ongoing evaluation of the cumulative effects of all CWPPRA projects throughout the coastal ecosystems of Louisiana. Simulations made by using the resampling methodology described in Steyer and others (2003) indicated that 100 randomly selected reference sites would accurately represent the true composition of coastwide vegetation at a 95 percent confidence level. However, in order to detect a 20 percent change in coastal marsh vegetation between two time periods, at least 80 percent of the time, approximately 400 reference sites were needed. Because of land rights and other technical issues, 390 sites with a fixed annual sampling design were approved and secured for CRMS data collection. These 390 CRMS sites are located within nine coastal basins and four CWPPRA regions, covering the entire Louisiana coast. Site construction and data collection began in 2005.

Because of the quantity of products and data that will be produced over the lifetime of the CRMS project, a website (http://www.lacoast.gov/crms) was designed to be a one-stop shop for CRMS information, products, and data. The ecological data available through the website are linked to the official Louisiana CPRA database – the Coastal Information Management System (CIMS), which houses all CWPPRA monitoring data, on topics such as the following: hydrology, herbaceous marsh vegetation, forested swamp vegetation, soil properties, soil accretion, and surface elevation. Data provided by the Louisiana CPRA are available for downloading at https://cims.coastal.louisiana.gov/. The basic viewer (under Mapping) on the CRMS Web site provides a user-friendly interface for viewing information on specific sampling sites, including photos, data summaries, and report cards. Analytical teams are developing mechanisms by which individual sampling sites can be assessed in relation to other sites within the same marsh type, hydrologic basin, and CWPPRA project. These multi-scale evaluations will be presented on a “Report Card” tab within the basic viewer. The CRMS program is as dynamic as the coastal habitats it monitors. The program continues to develop new products and analysis tools while providing data for model improvement and scientific research. The CRMS Web site is the current dissemination mechanism for all activities related to the program. For a beginner’s guide to retrieving CRMS data, visit https://www.lacoast.gov/new/Ed/CRMS_Manual.pdf.

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Reference:

Steyer, G.D., Sasser, C.E., Visser, J.M., Swensen, E.M., Nyman, J.A., and Raynie, R.C., 2003, A proposed coast-wide reference monitoring system for evaluating wetland restoration trajectories in Louisiana: Environmental Monitoring and Assessment, v. 81, p. 107–117.

Oyster Bayou Marsh Creation

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Altered hydrology, drought stress, saltwater intrusion and hurricane induced wetland losses have caused the area to undergo interior marsh breakup. Recent impacts from Hurricane Rita in 2005 and Hurricane Ike in 2008 have resulted in the coalescence of Oyster Lake with interior water bodies increasing wave/wake related erosion. Based on USGS hyper temporal data analysis (1984 to 2011), land loss for the area is -0.75% per year. The subsidence rate is estimated at 0.0 to1.0 ft per century (Coast 2050, Mud Lake mapping unit).

The project boundary encompasses 809 acres. Specific goals of the project are: 1) create 510 acres of saline marsh in recently formed shallow open water; 2) nourish 90 acres of existing saline marsh; 3) create 17,500 linear feet of terraces; and, 4) reduce wave/wake erosion.

Approximately 510 acres of marsh would be created and 90 acres would be nourished. Sediment needed for the fill would be mined approximately one and a half miles offshore in the Gulf of Mexico. Half of the created acres would be planted. Tidal creeks and ponds would be constructed prior to placement of dredged material and retention levees would be gapped to support estuarine fisheries access to achieve a functional marsh. Approximately 17,500 linear feet of earthen terraces would be constructed and planted.

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This project is in Region 4, Calcasieu-Sabine Basin, located west of the Calcasieu Ship Channel and south of the west fork of the Calcasieu River.

This project is on Priority Project List (PPL) 21.

The Oyster Bayou Marsh Creation project sponsors include:

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

 

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