Marshes within the Hog Bayou Watershed mapping unit are
stressed due to limited freshwater input and seasonal salinity
spikes exacerbated by construction of the Mermentau Ship
Channel. Other contributors to land loss in the area are
subsidence, compaction, and erosion of organic soils.
Currently, the project area is characterized as large, open
water with degraded areas of wetland vegetation and low
organic production. The dredging of the Mermentau Ship
Channel increased tidal amplitude and salt water intrusion
into the watershed.
The goal of the project is to create new wetland habitat,
restore degraded marsh, and reduce wave erosion of organic
soils. The project would promote the expansion of emergent
marsh and submerged aquatic vegetation throughout the
project area. Material dredged from the Gulf of Mexico will
be used to create and nourish approximately 420 acres of
marsh. Smooth cordgrass will be planted throughout the
area. To help facilitate estuarine fisheries access, constructed
retention levees will be degraded and approximately 11,756
linear feet of tidal creeks will be constructed.
The project is located in planning Region 4, Mermentau
Basin in Cameron Parish within the Hog Bayou Watershed
Coast 2050 Mapping Unit. The mapping unit is bordered by
Lower Mud Lake to the west, the Gulf of Mexico to the
south, Rockefeller Refuge to the east, and Louisiana
Highway 82 to the north.
This project is on Priority Project List (PPL) 23.
The South Grand Chenier Marsh Creation – Baker Tract sponsors include:
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.
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:
There are four different types of wetland marshes in Louisiana.
Due to Louisiana’s proximity to the Gulf of Mexico, the exchange between fresh and salt water along the coast is frequent. Depending on the location of the marsh, it could be classified as either freshwater, intermediate, brackish, or saltwater marsh. Marshes are categorized by the salinity, or salt content, of the water, and the location of marshes to the Gulf of Mexico often directly correlates with the salinity level. Generally following a salinity gradient, freshwater marshes are commonly situated furthest inland from the gulf with a salt content of 0 ppt (parts per thousand), intermediate marshes contain a salinity range of 0-5 ppt, brackish marshes have a range of 5-15 ppt, and saltwater marshes encompass a salt content of 15 ppt or greater. Within the marsh gradient are estuaries, where fresh and salt water mix and many wetland species spend their juvenile lives.