Len Bahr at lacoastpost.com has a fantasy: Cut back on the Morganza-to-the-Gulf, which comes with a $11 billion price tag and funnel some of that money to the diversion of freshwater to Bayou Lafourche and all the little bayous that spring from it, beginning with Bayou Terrebonne at Thibodaux. At present the freshwater diversion,which has been in the planning since 1998, comes with $100 million price tag or less.
Bayou Lafourche begin carrying the Mississippi to the Gulf of Mexico 1300 years ago. In time the Mississippi shifted to the modern channel.
In the years following European settlement, Bayou Lafourche flowed from the Mississippi at 5000 cubic feet per second, enough to flood Donaldsonville and the surrounding countryside.
To stop the flooding the bayou was closed at its head at the river in 1903. Within three years the residents of Bush Grove, several miles down on the bayou, found saltwater in their drinking water, which moved as far upstream as Thibodaux. At the tail end of the bayou saltwater intruded into all the little distributaries that branched off from Lafourche. The wetlands in the Terrebonne and Barataria basins deteriorated even though the Bayou Lafourche Freshwater District restored flow from the Mississippi in 1955.
Diverting freshwater to the coastal marshes in the Terrebonne and Barataria basins first appeared as a concept in the 1993 Louisiana Coastal Wetlands Restoration Plan. The goal of the proposal was to increase the flow of freshwater along Bayou Lafourche to coastal marshes south of Thibodaux–to Lake Fields, Lake Long, Grand Bayou, Bayou Terrebonne, the Houma Navigation Channel, Delta Farms in the Terrebonne basin and Bayou Perot and Bayou Rigolets in the Barataria basin. Its progress to actualization has been rocky.
The EPA and the Louisiana Department of Natural Resources formalized the concept in 1996 and proposed increasing the flow of water in Bayou Lafourche to 2000 cfs, only between January and June when the river would be high enough to make the siphon work. Such a diversion would meet needs of the marshes and the increasing demands for fresh drinking water in the communities along the bayou. The public expressed concern that more water in the bayou would flood them out and erode its banks.
The EPA revised the project, reduced the diversion to 1000 cfs, provided a constant flow year-round with attention to the fall when saltwater intrusion was the greatest, and incorporated channel improvements that addressed flooding and bank stability. The agency presented the revision to the public at four meetings in September 1998. Water levels and bank erosion still concerned the public. In October the Coastal Wetlands Planning, Protection and Restoration Act Task Force–whose members include representatives from the Corps of Engineers, the U.S. Fish and Wildlife Service, the National Oceanic and Atmospheric Administration, the National Resource Conservation Service, the EPA, and the Governor’s Office of Coastal Activities–voted fund $500,000 for the EPA’s initial engineering and design on the project, giving particular attention to engineering bank stability and water levels. And, the agency promised to work closely with the Corps of Engineers.
The following June the EPA listed the work that would be done–analyzing the soils along the bayou to draft its geologic profile, dividing it into reaches based on geologic and topographic similarities, analyzing cross sections for bank stability, coordinating with the U.S. Geological Survey to assess hydraulic data to assure that water flows at safe and acceptable levels while maintaining bank stability.
In June 2000 the EPA concluded that deepening Bayou Lafourche by dredging would increase its carrying capacity and return it to its function as a distributary of freshwater to the marshes without widening its existing channel or eroding its bank. More soil borings needed to be done to assure bank stability at Donaldsonville. And more information needed to be gathered about the design of a new pumping station and the installation of a sediment trap at Donaldsonville, which would hold down dredging costs.
The Coastal Wetlands Planning, Protection and Restoration Act Task Force approved the first phase of engineering and design. The Task Force with the EPA as the lead agency and the Louisiana DNR would share the $5 million cost of the first phase of engineering and design, at the end of which the work would be thirty percent complete and would then be reviewed.
The engineering and design process considered alternatives to using Bayou Lafourche to deliver Mississippi flows to the wetlands, including a by-pass channel around the most densely populated reach of the bayou that would tap the river at Smoke Bend upstream from Donaldsonville. It evaluated other diversion projects at Caernarvon, Davis Pond, and West Point a la Hache. And, it considered which beneficiaries would pay how much. At the conclusion of the process in May 2006, the engineers choose one of the 144 alternatives they considered for implementation.
Using the existing Bayou Lafourche channel would be the most cost-effective means of diverting freshwater from the Mississippi to the wetlands and the rate of 1000 to 1500 cfs. To do so would entail dredging 2.9 million yards of sediment to deepen the bayou between Donaldsonville and Thibodaux and building a new pump at Donaldsonville. The diversion would raise water levels a foot at Donaldsonville, two and a half feet south of the Thibodaux weir, and a foot at Lockport. The diversion would cost $180 million, half of which would go into dredging. The Technical Committee of Coastal Wetlands Planning, Protection and Restoration Act Task Force would meet and decide whether the project to go forward. At its July 13, 2006 meeting the Task Force put off its decision to October.
At the October meeting the Task Force engaged in a lively debate about whether to fund the engineering and design of the project to 95% completion at a cost of $5 million. The $180 million cost of the project was outside the CWPRRA’s budget for small projects. The Louisiana DNR feared transferring the project to the Louisiana Coastal Area Ecosystem Restoration Study (LAC) would lead to delay or even cancellation of the project, even through the project was one of five projects included in the LAC Study. If the project were transferred to the Corps of Engineers, funds would have to come out of a Water Resources Development Act. Congress had not passed a WRDA since 2000. The Technical Committee voted not to approve continued funding from CWPRRA and to transfer the diversion project to the LCA for completion.
A month later the Louisiana Coastal Protection and Restoration Authority Integrated Planning Team, set up in December 2005 in the wake of Katrina to develop and implement a comprehensive coastal protection plan, issued its first draft. Listed among the projects was the Bayou Lafourche diversion plan. In February 2007 when the state issued its list of projects that would be funded through the Louisiana Coastal Impact funds, the Louisiana DNR did not include the Bayou Lafourche Diversion among the diversion projects that would receive funding.
In September 2007 Congress passed the long awaited Water Resources Development Act and included the LCA plan in it. President George W. Bush vetoed the act in October. Congress overrode the veto in November.[i]
Read Len Bahr’s fantasy for Bayou Lafourche. It makes sense.
[i] Hallowell, Christopher, Holding Back the Sea, New York: HarperCollins, 2001, 210; U.S. Environmental Protection Agency, “Bayou Lafourche,” Bayou Lafourche Freshwater Diversion Updates, November 1998, June 1999, June 2000, October 25, 2001,
http://www.epa.gov/region6/water/ecopro/em/cwppra/blafourche/index.htm; CH2MHill, Mississippi River Water Reintroduction into Bayou Lafourche: Phase 1 Design Report, Prepared for the Louisiana Department of Natural Resources, December 2005, Introduction, http://data.lacoast.gov/reports/project/BA-25b/phase_1_section_1.pdf;The Mississippi Re-introduction into Bayou Lafourche, http://www.bayoulafourche.org; Coastal Wetlands Planning , Protection and Restoration Act, Task Force Meeting, October 18, 2006, 83, http://lacoast.gov/reports/tf/tf2006-10-18.pdf; Louisiana Coastal Protection and Restoration Authority integrated Planning Team, Comprehensive Coastal Protection Master Plan, Appendix A: The Long Term Plan, 107, http://www.louisianacoastalplanning.org/documents/Appendix%20A%20-%20Preliminary%20Draft%20-%20Comprehensive%20Coastal%20Protection%20Master%20Plan%20for%20Louisiana.pdf; Louisiana Department of Natural Resources, Draft: Louisiana Coastal Impact Assistance Plan, Executive Summary, http://dnr.louisiana.gov/crm/ciap/executivesummary.2007.02.06.pdf.