Terre aux Boeufs, the Violet Canal, and Fixing MRGO

Map of MRGO and the Bayou Terre aux Boeufs Ridge

It has been almost two years since the U.S. Army Corps of Engineers built a dam across MRGO at the Bayou la Loutre ridge. Now it is up to the engineers to figure out how to fill in the canal that was 600 feet wide when first dredged in the 1960s, but which eroded to 2500 feet wide by the time Katrina came along. Katrina destroyed St. Bernard Parish, which had been left without the protection of miles and miles of cypress swamp and marshes that eroded away after MRGO conveyed salt water into them. In addition the engineers built levees of sand to protect the parish.

So now the Corps of Engineers wants to dig another canal across the Terre aux Boeufs ridge between MRGO and the Mississippito convey freshwater and sediment into MRGO from the Mississippi at Meraux, where the river runs closest to the remaining wetlands that lie between the river and MRGO. This makes the residents of St. Bernard nervous, dig a new canal to fill an old canal. St. Bernard Parish would rather they use the old Violet Canal, which the engineers claim would be too expensive. Too many businesses line the canal and a bridge crosses it. They would have to be dealt with. It’s cheaper and easier to start fresh.

Violet Canal

The Violet Canal: The place where commercial fishing boats and their owners from the villages beyond the limits of the St. Bernard Parish hurricane protection system found safer harbor from Katrina. And, it is a second source of freshwater from the Mississippi to the wetlands, 7,000 feet east of the Violet diversion site. Opened in 1979 the Violet Siphons were a disappointment. They silted up easily and delivered water to the wetlands inconsistently and slowly, at a rate of 300 cubic feet per second. The Louisiana DNR looked into replacing siphons with a larger structure as early as 1987, at a time when the EPA noted that most of the freshwater diverted to the wetlands would be carried off by MRGO. Over the years the idea met with other roadblocks. It was too expensive.

The DNR would replace the siphon with a controlled gravity-flow diversion structure that would release water under LA 46 and into the existing Violet Canal. Violet Canal would be enlarged or, possibly, replaced. With initial funding from the state the DNR made preliminaries of the engineering and design of the project, investigated landrights and the existing conditions in the wetlands, devised the monitoring plan, and designed a hydrodynamic and salinity model to assess how water would circulate through the outfall area and its capacity based on a diversion of 2,500 to 5,000 cubic feet per second. The agency also devised alternatives to the primary plan. Continued funding was refused because the final cost of the project went beyond the budget limitations for Breaux Act projects. The Louisiana DNR looked to the Coastal Impact Assistance Program to fully fund the project.

After Katrina and the probability that MRGO would be closed, the project became viable. With the passage of the Federal Energy Bill of 2005 and the influx of money from the Coastal Impact Assistant Program, the State decided to try again and included the diversion in the 2007 Draft of the Louisiana Coastal Impact Assistance Plan. The reach of the new diversion project would extend well beyond restoring freshwater swamps to wetlands to restoring intermediate marshes to Lake Borgne to brackish marshes the Biloxi Marsh and Mississippi Sound. A stunning 235,000 acres would be enhanced.[i]

MRGO at Ycloskey

MSNBC has an more extensive article that includes a picture of a place I think I visited in 1995 and made my own image. It’s a cattle pasture with a ditch running through it and the skeletons of live oaks, which have drowned because the pasture like the rest of the Louisiana wetlands is sinking. This is the Bayou Terre aux Boeufs ridge, laid down by the Mississippi when it flowed along the bayou of the same name when it formed the St. Bernard delta lobe 4500 years ago. It and the Bayou la Loutre ridge were the hydrological barrier between the Borgne-Biloxi estuary on the north and the Caernarvon-Terre aux Boeufs estuary on the south in Breton Sound.

Its integrity was severed in 1963 when the Corps of Engineers dredged MRGO, cut through the ridge, and altered the landscape, converting the ridge downstream of the channel into an island, conveying saltwater into the fresh marshes and swamps that protected New Orleans, leading to the deterioration of habitat on the ridge, and undermining the ridge’s role as a hydrologic barrier between the two estuaries. The dense oak forest that once populated the ridge declined.[i]

Terre aux Boeufs near Meraux, Louisiana

“Near the shores of the Gulf of Mexico are several permanently located families, Acadians or from among those who now live at Terre Aux Boeufs, all that is left of a much larger number who immigrated to that location. Their miserable existence is supported mainly by fishing, especially in gathering oysters, which they bring to town. And that area of lakes, bayous, oak trees, prairies, cypress groves, canes or reeds, mud flats, or hazardous places–so close to New Orleans–is still known in detail only by hunters.”–James Pitot, 1802[ii]

“On the east side of the Mississippi, and about twelve miles below New Orleans, a dry strip of land extends from the river in a direction towards the lakes, where it terminates at the distance of twenty miles. This tongue of land, called the Terre au Boeufs, is about a mile in width, and divided in the center by a creek or bayou; and like the Mississippi, is bounded on each side by cypress swamps.” –Major Amos Stoddard, 1812[iii]

Terre aux Boeufs is a settlement, which is connected with those on the Mississippi, and winds along both banks of a small ancient outlet. The lands upon the Terre aux Beoufs are excellent. Sugar, cotton, and carrel are the staples of this settlement, and some fine sugar-houses are established. The adjacent country towards Lake Borgne and Chandeleur bay is and open grassy morass.

The Terre aux Boeufs abound in excellent live oak, which is in a state of rapid distruction, occasioned by burning the cane and grass intermingled with the trees, and by clearing the land. –William Darby, 1818

Spanish immigrants from the Canary Islands, Islenos, first came to St. Bernard Parish in 1779. They settled along the Bayou la Loutre ridge and brought with them their tradition of domesticating their horned cattle, which had thick hides, were impervious to mosquitoes, and adapted well to southeastern Louisiana conditions. Ranchers from as far away as East Texas drove their herds of cattle to St. Bernard Parish for training; hence, the name of the region, Terre aux Boeufs. They had been farmers in the Canaries, they became farmers on Terre aux Boeufs and worked the sugar plantations at Chalmette, Violet, Caernarvon, Poydras, and Reggio. And, they lived the Louisiana year–fishing, shrimping, trapping, and oyster dredging in the waters of Breton Sound and Lake Borgne. They sold their catch in New Orleans.

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[i] U.S. Environmental Protection Agency, and Louisiana Geological Survey, Saving Louisiana’s Coastal Wetlands,: The Need for a Long-Tern Plan of Action,  April 1987, 27,http://www.epa.gov/climatechange/effects/downloads/louisiana_3.pdf; Louisiana Department of Natural Resources, “Violet Freshwater Diversion, St. Bernard Parish, LA, http://dnr.louisiana.gov/SEC/MGTFIN/Contract/rsiq-2503-08-21_enc1.pdf; Louisiana Department of Natural Resources, Draft: Louisiana Coastal Impact Assistance Plan, Executive Summary,  February 2007, http://dnr.louisiana.gov/crm/ciap/executivesummary.2007.02.06.pdf; Louisiana Department of Natural Resources, “River Reintroduction at Violet, Louisiana: Project Fact Sheet,” April 2006,http://dnr.louisiana.gov/crm/ciap/project-proposals/Region1/StBernard/1F-StB.%20violet.pdf.

[i] St. Bernard Parish’s LosIslenos.org, “History–How We Began,” http://www.losislenos.org/history.htm; Encyclopedia Louisiana, “Communities of St. Bernard Parish,” http://enlou.com/maps/stbernard_map.htm ; Hansen, Harry, editor,Louisiana: A Guide to the State, New York: Hastings House, 1971, 490; Lake Pontchartrain Basin Foundation, Comprehensive Habitat Management Plan for the Lake Pontchartrain Basin, February 28, 2006, 79, 100, 102,http://www.saveourlake.org/pdfs/JL/CHMP_final_%2022706.pdf.

[ii] Pitot, James, Observations on the Colony of Louisiana from 1796 t0 1802, Translated from the French by Henry C. Pitot, Baton Rouge: Louisiana State University Press, 1979, 113.

[iii] Stoddard, Major Amos, Sketches, Historical and Descriptive of Louisiana, Philadelphia: Mathew Carey, 1812, 161.