Barataria Basin
The Barataria Basin is an
irregularly shaped area bounded on each side by a distributary ridge formed by
the present and a former channel of the Mississippi River. A chain of barrier
islands separates the basin from the Gulf of Mexico. In the northern half of the
basin, which is segregated by the Gulf Intracoastal Waterway (GIWW), several
large lakes occupy the sump position approximately half-way between the ridges.
The southern half of the basin consists of tidally influenced marshes connected
to a large bay system behind the barrier islands. The basin contains 152,120
acres of swamp, 173,320 acres of fresh marsh, 59,490 acres of intermediate
marsh, 102,720 acres of brackish marsh, and 133,600 acres of saline marsh.
Within the Barataria Basin, wetland loss rates averaged nearly 5,700 acres per year between 1974 and 1990. During this period, the highest rates of loss occurred in the Grande Cheniere and Bay Regions. Wetland loss within the Barataria Basin is attributed to the combination of natural erosional processes of sea-level rise, subsidence, winds, tides, currents, and herbivory, and the human activities of channelization, levee construction, and development.
Freshwater and sediment input to the Barataria Basin was virtually eliminated by the erection of flood protection levees along the Mississippi River and the closure of Bayou Lafourche at Donaldsonville; therefore, the only significant source of fresh water for the basin is rainfall. Only a small amount of riverine input, designed to mimic a natural crevasse, is introduced into the basin's wetlands through the recently completed siphons at Naomi and West Pointe a la Hache. This lack of fresh water, and the loss of the accompanying sediments, nutrients, and hydrologic influence, forms the most critical problem of the Barataria Basin.
The second critical problem is the erosion of the barrier island chain. As individual islands are reshaped or breached, or succumb to the forces of the Gulf of Mexico, passes widen and deepen with the result that a greater volume of water is exchanged during each tide.
Four islands-West Grand Terre, East Grand Terre, Grand Pierre, and Cheniere Ronquille-had a combined area of just over 1,800 acres in 1990. By 2015, the islands will be reduced to a total of approximately 1,000 acres. East Grand Terre and Grand Pierre are predicted to disappear by 2045, and the remaining islands will consist of only 400 acres.
The result of the problems described above is an increase in tidal amplitude in the marshes in the central basin. This cumulative effect is exemplified by increased salinities in the lower half of the basin, increased land loss rates, and change in vegetation.
Site-specific problems of shoreline erosion, especially in areas with organic soils, poor drainage, salinity stress, and herbivory, are apparent throughout the basin. Solving these problems is important, but less urgent than solving the critical problems described above.
Basin-Wide Land Loss Map for
Barataria Basin. |
Basin-Wide Habitats Maps for Barataria
Basin. |
(Time lapsed animation of basin from 1956 to 1993.)
CWPPRA Restoration Sites for the Barataria Basin
| PPL | Number | Agency | Project Name |
| 11 | BA-38 | NMFS | Barataria Barrier Island Complex Project: Pelican Island and Pass La Mer to Chaland Pass Restoration |
| 9 | BA-27c | NRCS | Barataria Basin Landbridge Shoreline Protection, Phase 3 |
| 11 | BA-27d | NRCS | Barataria Basin Landbridge Shoreline Protection, Phase 4 |
| 7 | BA-27 | NRCS | Barataria Basin Landbridge Shoreline Protection, Phases 1 and 2 |
| 6 | BA-26 | NRCS | Barataria Bay Waterway East Side Shoreline Protection |
| 4 | BA-23 | NRCS | Barataria Bay Waterway West Side Shoreline Protection |
| 1 | BA-19 | COE | Barataria Bay Waterway Wetland Restoration |
| 17 | BA-48 | NMFS | Bayou Dupont Ridge Creation and Marsh Restoration |
| 4 | BA-22 | NRCS | Bayou L'Ours Ridge Hydrologic Restoration (Deauthorized) |
| 3 | BA-21 | NMFS | Bayou Perot/Bayou Rigolettes Marsh Restoration (Deauthorized) |
| 11 | BA-36 | USFWS | Dedicated Dredging on the Barataria Basin Landbridge |
| 10 | BA-33 | COE | Delta Building Diversion at Myrtle Grove |
| 9 | BA-30 | NMFS | East/West Grand Terre Islands Restoration |
| 1 | BA-18 | NMFS | Fourchon Hydrologic Restoration (Deauthorized) |
| 1 | BA-02 | NRCS | GIWW (Gulf Intracoastal Waterway) to Clovelly Hydrologic Restoration |
| 2 | BA-20 | NRCS | Jonathan Davis Wetland Restoration |
| 9 | BA-29 | EPA | LA Highway 1 Marsh Creation (Deauthorized) |
| 15 | BA-42 | USFWS | Lake Hermitage Marsh Creation |
| 3 | BA-15 | NMFS | Lake Salvador Shore Protection Demonstration |
| 11 | BA-37 | NMFS | Little Lake Shoreline Protection/Dedicated Dredging near Round Lake |
| 5 | BA-25b | EPA | Mississippi River Reintroduction Into Bayou Lafourche (Deauthorized) |
| 10 | BA-34 | EPA | Mississippi River Reintroduction Into Northwest Barataria Basin |
| 12 | BA-39 | EPA | Mississippi River Sediment Delivery System - Bayou Dupont |
| 5 | BA-24 | NMFS | Myrtle Grove Siphon (Deauthorized) |
| 5 | BA-03c | NRCS | Naomi Outfall Management |
| 11 | BA-35 | NMFS | Pass Chaland to Grand Bayou Pass Barrier Shoreline Restoration |
| 14 | BA-40 | NMFS | Riverine Sand Mining/Scofield Island Restoration |
| 14 | BA-41 | NRCS | South Shore of The Pen Shoreline Protection and Marsh Creation |
| 7 | BA-28 | NMFS | Vegetative Plantings of a Dredged Material Disposal Site on Grand Terre Island |
| 17 | BA-47 | NRCS | West Pointe a la Hache Marsh Creation |
| 3 | BA-04c | NRCS | West Pointe a la Hache Outfall Management |
31 projects listed
PPL stands for "Priority Project List"