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[Davis Pond Construction Contract Info] | |
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Davis Pond Freshwater Diversion Structure
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The Davis Pond Freshwater Diversion Structure will imitate historic spring floods, providing a controlled flow of fresh water and nutrients from the Mississippi River into a target area in the Barataria Bay estuary. Located on the west bank of St. Charles Parish, two miles below Luling, Davis Pond is expected to restore former ecological conditions by combatting land loss, enhancing vegetation and improving fish and wildlife habitat.
| Davis Pond Project Area located along the Mississippi River on the West Bank of St. Charles Parish. |
This will be accomplished with four iron-gated 14' x 14' box culverts built into the Mississippi River levee. An inflow channel 535' long x 85' wide will direct river water into the structure, while an outflow channel more than 11,000' long x 120' wide will extend behind the structure into the ponding area and, ultimately, into the estuary. The total project area comprises 10,084 acres, including the 9,200-acre ponding area.
| Construction features in the Davis Pond Project Area. |
When completed, Davis Pond will be able to divert up to 10,650 cubic feet per second (cfs) of fresh water. Diversions through the structure will occur under regulated conditions determined by monitoring basin salinities and fish and wildlife resources.
During the next 50 years, Davis Pond will preserve about 33,000 acres of marsh and benefit 777,000 acres of marshes and bays. These shallow areas support a bountiful oyster crop each year, and they provide important nursery habitat for shrimp and fish. Similarly, the marsh provides food and nesting habitat for fur-bearing animals and migratory waterfowl. By improving existing marsh conditions, the project is expected to provide average annual benefits of $15 million for fish and wildlife, plus $300,000 for recreation.
Davis Pond is a feature of the Mississippi Delta Region Project, and was authorized by the Flood Control Act of 1965 and modified by the Water Resources Development Acts of 1974, 1986 and 1996. The total estimated cost of the project is $106 million, with the federal government paying 75% and the state paying 25%. To expedite the project, Louisiana volunteered to contribute 25% toward the project; the Project Cooperation Agreement between the state and the federal government was signed in April 1993. Construction began in January 1997.
Eight primary construction contracts are associated with this project. Six contracts have been awarded to date; for the pumping station (C.R. Pittman Construction), the Highway 90 Bridge (River Road Construction), the diversion structure itself (Maharrey-Houston Construction), the east guide levee and weir (Weeks Marine, Inc.) and the west guide levee (J. Caldarera & Company, Inc.), and the Burlington Northern Railroad Bridge (Souter Construction Co.). Two Contracts remain to be awarded in early 2000. The project should be diverting flows into the Barataria Basin in the year 2001.
Senator Breaux hailed the project as a new beginning and commended those who are committed to restoring the coast of Louisiana. “Once you lose the very essence of your state and territory, it never comes back,” he said. “We’re restoring to the Mississippi River its ability to flood. But we will control that flooding in a positive sense to rebuild our state.”
In addition to Davis Pond, two other structures, one completed and one proposed, are important to the future of Louisiana's coast. The Caernarvon Freshwater Diversion Structure, 15 miles below New Orleans, was completed in February 1991 at a cost of $25.9 million. Since it began operating, new land and marsh vegetation have appeared and oyster production on the public grounds has more than tripled. During the next 50 years, Caernarvon is expected to re-establish favorable salinity conditions in the area, further enhancing fish and wildlife productivity.
| The Davis Pond Freshwater Diversion Structure site, looking south from the Mississippi River toward the Barataria Bay estuary. The cofferdam in the foreground provides protection from possible flood waters. |
The proposed Bonnet Carre Freshwater Diversion Structure would be located on the east bank of the river, within the Bonnet Carre Spillway. It is designed to divert flows up to 25,000 cfs into the Lake Pontchartrain Basin and western Mississippi Sound. This would reduce saltwater intrusion and result in a healthier marsh and increased production of oysters, shrimp, crabs and fish. Construction of this $87 million project has not been scheduled.
| The Davis Pond Freshwater Diversion Structure site, looking downriver from the west bank of the Mississippi River. The state highway and railroad, now detoured to the right, will pass over the structure when completed. |
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