Giant Salvinia

Giant Salvinia, or Salvinia adnata, often referred to as the green monster, poses a serious threat to wetland ecosystems. This highly invasive, aquatic plant species is native to Brazil. The floating aquatic fern has leaves covered with small hairs on the upper surface that become compressed into chains forming a dense, compiled mat-like structure. In the United States, it’s difficult to control Giant Salvinia due to the lack of legal herbicides that work efficiently to stop it from spreading. Giant Salvinia was first spotted in Chenier Plain Marshes in 2009; since then it has spread throughout.

This non-native plant species has an exceedingly rapid growth rate, and under the right conditions it can potentially take over a waterway causing catastrophic results. The mat blocks sunlight from penetrating into the water, ultimately killing phytoplankton and other aquatic plant species, as well as exhausting oxygen levels, which alters the area as a waterfowl habitat and degrades the water quality for fish. Giant Salvinia is unintentionally spread to new water bodies on boats and fishing gear. One way to prevent the expansion of Giant Salvinia is to properly clean boating equipment and vessels of any plant fragments. These plant fragments, garden, and aquarium plants should all be discarded properly in the trash and kept out of water bodies. It is important to properly control and dispose of the plant material in order to keep lakes, rivers, ponds and other freshwater wetlands functioning properly without the disturbance caused by Giant Salvinia.

Cyrtobagous salviniae, a species of weevil, is often referred to as the salvinia weevil due to being a biological pest control against the highly invasive Giant Salvinia. For more information on Giant Salvinia and CWPPRA’s efforts to control this invasive plant species visit the Coastwide Salvinia Weevil Propagation Facility (LA-284) Fact Sheet.

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Classification of Marshes

Marsh is a type of wetland that is continually flooded with water. Marshes can be found both on the coast or inland. Most of the water present is due to surface water; however, some groundwater also fills this wetland area.

Marshes can be divided into two main categories: non-tidal and tidal.

Non-tidal Marshes:

  • Most widely distributed and productive wetlands in North America
  • Occur along the boundaries of lakes, streams, rivers and ponds
  • Mostly freshwater, but some are brackish or alkaline
  • Beneath these wetlands lie highly organic soils
  • You might spot cattails, lily pads, reeds, and an array of waterfowl in this wetland
  • Alleviate flood damage and filter surface runoff

Tidal Marshes:

  • Found along protected coastlines and impacted by ocean tides
  • Present along the Gulf of Mexico
  • Some are freshwater or brackish, mostly saline
  • Provide shelter and nesting sites for migratory fowl
  • Covered by smooth cordgrass, spike grass, and salt meadow rush
  • Slow down shoreline erosion

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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.

LaBranche East Marsh Creation

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Dredging of access and flotation canals for the construction
of I-10 and the Illinois Central Railroad resulted in increased
salinity and altered hydrology in the area that exacerbated
the conversion of wetland vegetation into shallow open
water bodies.

The project’s primary goal is to restore marsh that has been
converted to open water. Project implementation will result
in an increase of wildlife and fisheries habitat, acreage and
diversity, along with improving water quality. In addition,
the project will provide a storm buffer protection to I-10, the
region’s primary westward hurricane evacuation route, and
complement hurricane protection measures in the area.
Project features consist of the creation of 729 acres of marsh
and the nourishment of 202 acres of existing marsh using
dedicated dredging from Lake Pontchartrain. In addition,
10,000 linear feet of tidal creeks will be created. The marsh
creation area will have a target elevation the same as average
healthy marsh for this region. Plans are to place the dredge
material in the target area with the use of low level, noncontinuous
retention dikes along the edge of the project area
allowing overtopping of material to nourish the marsh fringe.
Vegetative plantings will be utilized in the areas deemed
most critical by the project team. Successful wetland
restoration in the immediate area (PO-17) clearly
demonstrates the suitability and stability of soil and material
availability from a sustainable borrow area.

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The project features are located between Lake Pontchartrain
and I-10 in St. Charles Parish, Louisiana. It is bounded on
the west by the Fall Canal and the Bayou LaBranche
Wetland Creation Project (PO-17) and the east by a pipeline
canal.

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

The LaBranche East Marsh Creation project sponsors include:

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

 

Cheniere Ronquille Barrier Island Restoration

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This area is undergoing shoreline erosion, interior wetland
loss, overwash, and breakup. The Gulf shoreline erosion rate
has doubled from 1988 to 2006. Project area marshes also
are being eroded at -11.8 ft/yr between 2003 to 2006 as well
as being converted to open water from internal breakup.

Restoration would expand the Gulf shoreline structural
integrity and associated protection by tying into two recently
constructed projects to the east and address one of the
remaining reaches of the Barataria/Plaquemines shoreline.
The design includes fill for a beach and dune plus 20-years
of advanced maintenance fill, as well as fill for marsh
creation/nourishment. The location of the type and amount
of sediment needed to construct this project already has been
identified under the East Grand Terre Project that is presently
under construction. Approximately 127 acres of beach/dune
fill would be constructed and approximately 259 acres of
marsh creation/nourishment would be constructed. Intensive
dune plantings would be conducted by seeding and installing
approved nursery stock. About half of the
marsh platform would be planted with cordgrass and
portions of the dune, swale, and marsh would be planted
with appropriate woody species. Containment dikes would
be breached no later than year three to allow tidal exchange
with the created marsh.

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The project is located in Region 2, within the Barataria Basin
portion of Plaquemines Parish.

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

The Cheniere Ronquille Barrier Island Restoration project sponsors include:

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

 

Cameron-Creole Watershed Grand Bayou Marsh Creation

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Approximately 14,390 acres (32%) of the Cameron-Creole
Watershed Project (CCWP) marshes were lost to open water
from 1932 to 1990 at an average loss rate of 248 acres/year
(0.55 percent/year) due to subsidence and saltwater intrusion
from the Calcasieu Ship Channel. The
CCWP was implemented by the NRCS in 1989 to reduce
saltwater intrusion and stimulate restoration through
revegetation. Hurricanes Rita and Ike in 2005 and 2008
breached the watershed levee scouring the marsh and
allowing higher Calcasieu Lake salinities to enter the
watershed causing more land loss. The Calcasieu-Sabine
Basin lost 28 square miles (17,920 acres) (4.4%) as a result
of Hurricane Rita (Barras et al. 2006). Land loss is estimated
to be 1.33 percent/year based on USGS data from 1985 to
2009 within the extended project boundary.

Project goals include restoring and nourishing hurricane-scoured
marsh in the Cameron Prairie National Wildlife
Refuge and adjacent brackish marshes of the Calcasieu Lake
estuary. Approximately 3 million cubic yards of material
would be dredged from a borrow site proposed in Calcasieu
Lake and placed into two marsh creation areas north of
Grand Bayou to restore 609 acres and nourish approximately
7 acres of brackish marsh. The borrow site would be
designed to avoid and minimize impacts to oysters and other
sensitive aquatic habitat. Tidal creeks would be constructed
prior to placement of dredge material and retention levees
would be gapped to support estuarine fisheries access and
to achieve a functional marsh. The project would result in
approximately 534 net acres of brackish marsh over the 20-
year project life.

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This project is located in Region 4, Calcasieu-Sabine Basin,
Cameron Parish, 6 miles northeast from Cameron, LA, on
the Cameron Prairie NWR and Miami Corporation property
north of Grand Bayou.

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

The Cameron-Creole Watershed Grand Bayou Marsh Creation sponsors include:

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

 

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.