Lost Lake Marsh Creation and Hydrologic Restoration

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Significant marsh loss has occurred between Lake Pagie and
Bayou DeCade to the point that little structural framework
remains separating those two waterbodies. Northeast of Lost
Lake, interior marsh breakup has resulted in large, interior
ponds where wind/wave energy continues to result in marsh
loss. West of Lost Lake, interior breakup has occurred as
a result of ponding and the periodic entrapment of higher
salinity waters during storm events.

Approximately 465 acres of marsh will be created between
Lake Pagie and Bayou DeCade, north of Bayou DeCade,
and along the northwestern Lost Lake shoreline. Marsh
creation will restore/protect some key features of structural
framework (i.e., lake rim and bayou bank) within the area.
Borrow material will be taken from within Lost Lake and
pumped via a hydraulic dredge into the marsh creation sites.
Tidal creeks will be constructed within the marsh creation
cells to ensure tidal connectivity and prevent ponding within
the created marsh. In addition, 30,000 linear feet (22 acres)
of terraces will be constructed to reduce fetch in an area of
deteriorated marsh north of Bayou DeCade.
Two fixed-crest weirs along Carencro Bayou will be replaced
with variable-crest structures. At certain times of the year,
Carencro Bayou is an excellent source of fresh water and
sediments from the Atchafalaya River/Four League Bay
system. However, delivery of that water into the marshes
west of Lost Lake is limited by fixed-crest weirs which limit
water exchange. Installing structures with bays/gates will
increase freshwater and sediment delivery. In addition, two
fixed-crest weirs near Rice Bayou will be replaced with
variable-crest structures to provide flow-through conditions
in the system (i.e., water enters the system from Carencro
Bayou and exits through the structures near Rice Bayou).
A similar structure will be installed along Little Carencro
Bayou to increase freshwater and sediment delivery into the
marshes north of Lost Lake.

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The project is located in the Terrebonne Basin, Terrebonne
Parish, near the vicinity of Lost Lake.

This project is on Project Priority List (PPL) 19.

The Lost Lake Marsh Creation and Hydrologic Restoration project sponsors include:

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

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Wetlands around the World

Let’s take a brief glance at wetlands around the world. Wetlands exist in many climates and on every continent except Antarctica. Considered the most biologically diverse of all ecosystems, wetlands provide habitat for an array of water, land, and migratory bird species. The wetlands highlighted include swamps, bogs, marshes, estuaries, floodplains, lakes and many other types.

The Pantanal

The Pantanal is located in the heart of South America and is the world’s largest wetland that has not been significantly modified by humans. The Pantanal is often referred to as South America’s biggest biodiversity star stretching across Brazil, Bolivia, and Paraguay. Its complex system of marshlands, floodplains, lagoons and interconnected drainage lines is home to over 4,700 species of plants and animals. The array of life in the Pantanal relies on an annual flooding cycle. The cycle of waters rising and then receding through the dry season nurtures a biologically diverse group of plants and is essential to preserve a healthy ecosystem.

Camargue

The Camargue, also referred to as the Rhone River Delta, is an alluvial plain located in the Southeast of France. Roughly a third of the Camargue wetlands are either lakes or marsh. This wetland is one of the most highly rated places in Europe for birdwatching. The area is historically famous for the greater flamingo and Camargue’s horses. If you are enticed to visit the Camargue, be sure to look into horseback riding on this special breed of horses.

Kafue Flats

Located in central Zambia, the Kafue flats consist of a unique variety of wetland types. The landscape located along the Kafue River includes grasslands, lagoons, swamps and marshes. This wetland is extremely important to Zambia for hosting wildlife, fishing, sugarcane farming and the production of hydro-electric power. Within the Kafue National Park you can spot a number of safari camps and lodges that have brought new interest to the area and attract many tourists.

kafue flats

Sundarbans

The meaning of “Sundarbans” is beautiful forests, which perfectly fits the name for the largest mangrove forest in the world. The region is also home to Sundari trees growing in salty coastal waters. These are a special kind of mangrove tree with roots called pneumatophores that emerge above the ground and aid in gaseous exchange. Along with serving as home to Sundari trees, this wetland region has possibly the largest population of Bengal tigers in the world. These tigers can be found swimming in the saline waters of this unique habitat in the same areas used by people.

sundarbans

Freshwater Wetlands

Freshwater habitats come in many forms ranging from glaciers to lakes, rivers, and wetlands. These freshwater ecosystems represent less than one percent of the planet’s surface while supporting over 100,000 species including but not limited to fish, frogs, worms, crawfish, and birds and mammals nesting and feeding in wetland vegetation. While serving as habitat for a large number of animals, freshwater wetlands are also home to a variety of plant types. Cattails are a common sight around freshwater lakes and marshes and help in maintaining a healthy ecosystem by filtering runoff as it flows into lakes and serving as a protectant against shoreline erosion. Floating plants, such as duckweed, are a favorite food for many ducks and geese that populate the area.

Freshwater wetlands may stay wet year-round or evaporate during the dry season. Freshwater habitats are some of the most endangered habitats in the world. Human development, agriculture, and pollution are leading factors that put the availability of freshwater at risk. Saltwater intrusion is another underlying factor interrupting the natural conditions of water quality. These impacts have extreme consequences for our freshwater biodiversity, economy, and our well-being. Louisiana’s freshwater wetlands along the coast and other areas are disappearing at a high rate. The Coastal Wetlands Planning, Protection, and Restoration Act implements projects in an effort to preserve freshwater ecosystems.

 

Benefits of Wetlands

Wetlands have long been considered an obstruction to development. Nearly a century ago, it was believed that wetlands did not provide substantial benefits to the environment and were deemed worthless. Wetlands were drained or filled to make room for further development, such as roads and homes. Today, scientists recognize the environmental benefits that wetlands provide and are encouraging us to preserve this environmental resource. Although we are still losing wetlands, our improved understanding of this dynamic ecosystem and the benefits it provides seems to be contributing to a decreasing loss of wetlands.

Wetlands are valuable in the fact that they provide water purification, flood protection, erosion control, groundwater recharge and discharge, and streamflow maintenance. Along with these benefits, wetlands provide habitat for a large percentage of threatened and endangered species, as well as fish and other wildlife. How a particular wetland functions and benefits the environment depends on its location and type. Wetlands take many forms including marshes, estuaries, bogs, lakes, coral reefs, and floodplains, just to name a few. Wetlands also provide recreational benefits, such as fishing, birding, nature photography, hiking, and kayaking. If you are feeling anxious to seek outdoor activity, look no further than the wetlands near you.

A partially filled or otherwise damaged wetland only reaches its minimal potential to provide all of these environmental benefits. If we want wetlands to continue to perform their ecological functions to the best of their ability, we have to protect them. Take action to help preserve one of the most biologically diverse but undervalued ecosystems.

 

Wetland Biome

Fun Fact:

Animal diversity in the wetland biome is greater than in any other biome type.

Wetland biomes are the perfect place for a variety of plants and animals to thrive due to the climate, food availability, and shelter provided. Amphibians and reptiles do particularly well in this environment. Some reptiles, such as turtles, need wetlands because they either live in water for much of their lives or largely rely on water for their survival. Wetlands support a variety of animals that provide plentiful food sources for reptiles. Snakes spend time around rivers and wetlands where there are food sources such as frogs and bird eggs.

 

Other species that populate the wetland biome are birds. Wetlands are an important habitat for birds that are breeding, nesting, and rearing young, and some bird species, stop to feed in wetlands along their migration route. The value of a wetland to a specific bird species is dependent upon the presence of surface water and the duration and timing of flooding, for example great egrets may nest in trees above water for protection from predators. The geographic location of a wetland also determines how and when birds will use it.

 

Alligators and crocodiles are the largest animals found in the wetland biome. The type of water found will strongly affect the types of life that survive there. When salt is present in the water, you might find shrimp and shellfish which are some of the smallest wetland animals.

June — Great Outdoors Month

While there are some people who cannot spend enough time outdoors, enjoying all of nature’s gifts, there are others who need a little more motivation to get outside and seek the beauty of our outdoors. What better time for either party to embrace the outdoor spirit of America than in the month of June, Great Outdoors Month. The month kicks off with a Presidential Proclamation, which advocates for all Americans to visit the great outdoors and to protect our nation’s legacy by conserving our lands for future generations. The Proclamation discusses the numerous possibilities for Americans to explore, play, and grow together through outdoor activities. Any activities from hiking to canoeing to wildlife watching, hunting, or fishing can involve kids by being healthy, active, and energized.

More and more Americans are seeking healthy and fun outlets as ways to stay active. The outdoor recreation community is situated in an exemplary position to help people lead a healthier lifestyle by welcoming them and providing guidance on how to take advantage of the great outdoors. Wetlands provide recreational opportunities such as fishing, canoeing, hiking, bird watching, and waterfowl hunting, just to name a few. One of the largest and most avid groups of people using wetlands is waterfowl hunters. There are an estimated 3 million migratory bird hunters in the United States. This year, new studies by the recreation community will record data on the key role outdoor recreation plays in local, state, and national economies. Outdoor recreation is an economic powerhouse in our country generating nearly $887 billion in consumer spending each year and creating 7.6 million jobs. Great Outdoors Month is designed to highlight the benefits of getting involved with our great outdoors and enjoying natural resources, such as forests, parks, refuges, and other public land and waters.

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.