Freshwater Bayou Bank Stabilization (ME-13)

By placing riprap in front of the existing shoreline, further wetland loss will be decreased dramatically. It is anticipated that open water areas behind the rock structure will accumulate sediments and eventually become vegetated.

Location

This project is located along the west bank of Freshwater Bayou Canal near Little Vermilion Bay, 4 miles southwest of Intracoastal City, Louisiana, in Vermilion Parish. It
extends north from North Prong and Belle Isle Bayou to Sixmile Canal.

Problems

Increased tidal action, saltwater intrusion, and boat wakes have accelerated erosion long the banks of the Freshwater Bayou Canal. The spoil banks have completely eroded in some areas. The remaining spoil banks along the southern reach of the project area separate Freshwater Bayou Canal from several interior marsh ponds. If the banks breach, shoreline erosion will accelerate interior marsh loss.

Restoration Strategy

The objective of this project was to prevent further wetland loss through the reduction of bank erosion and subsequent tidal scour of shoreline marshes. Approximately 23,193 linear feet of freestanding rock dike were constructed in shallow water along the west bank of Freshwater Bayou Canal (from its confluence with Sixmile Canal on the northern end and North Prong to the south).

Progress to Date

The local cost share for this project was provided by Acadian Gas Company. Construction began in March 1998 and was completed in May 1998. The monitoring plan was approved in February 1997. To date, monitoring has consisted of documenting the pre-construction shoreline position relative to the rock dike and a land-to-water analysis of the preconstruction aerial photography that was taken in January 1997. This project is on Priority Project List 5.

The project is on Priority Project List (PPL) 5.

The Federal Sponsor is National Resources Conservation Service

The Local Sponsor is CPRA.

Approved Date: 1996
Project Area: 1,724 acres
Approved Funds: $5.56 M
Total Est. Cost: $8.91 M
Net Benefit After 20 Years: 511 acres
Status: Completed June 1998
Project Type: Shoreline Protection

Pecan Island Terracing (ME-14)

In the mid-1950s continuous dikes were constructed and water was pumped off the marsh, transforming it into dry pastureland. As a result of oxidation, the soil elevation has subsided 1 to 2 feet. Deterioration and loss of the perimeter levees in recent years has converted the entire area into a shallow, open water lake with a few small marsh islands resulting in a net loss of fisheries habitat.

The restoration project will reduce marsh erosion by creating emergent terraces designed to minimize wave fetch across open water and, at the same time, creating linear marsh features. Future marsh loss will be prevented and brackish marsh will be restored. Construction of the earthen terraces in shallow water areas will also convert areas of open water back to vegetated marsh creating more habitat for fish and shellfish. The project calls for constructing adjacent terrace cells in a staggered gap formation, each bordered by terraces made from dredged material. Terraces will be built and planted with smooth cordgrass (Spartina alterniflora), and California bulrush (Scirpus californicus). Plantings may also occur on the north side of the terracing area.

 

This project is located in southeastern Vermilion Parish, Louisiana, approximately 5 miles north of the Gulf of Mexico just south of Pecan Island and Louisiana Highway 82.

The project construction was completed in August 2003, initially creating over 122 acres of emergent marsh. The monitoring plan was finalized in November 2001 and data collection has been ongoing since that time.

This project is on Priority Project List 7.

The Federal Sponsor is NOAA

The Local Sponsor is CPRA