London Avenue Canal

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The London Avenue Canal is a drainage canal in New Orleans, Louisiana, used for pumping rain water into Lake Pontchartrain. The Canal runs through the 7th Ward of New Orleans from the Gentilly area to the Lakefront.

London Avenue Canal; view from Robert E. Lee Bridge looking riverwards, 19 October 2005. Intact concrete flood wall atop levee visible at left. At right, incompletely repaired upper breach visible.

The Canal was constructed in the first half of the 19th century, commissioned by Alexander Milne, who owned large tracts of land that would later become part of the city of New Orleans but were at the time mostly swamp. The canal originally served to commerce of small boat traffic from Lake Pontchartrain to the "Back of Town" section of New Orleans in addition to swamp drainage (which early on it did little of). By the end of the 19th century, with most commerce shifted to other canals specifically designed for shipping, the London Avenue Canal had achieved its modern function to take flow of drainage mechanically pumped from the streets of the City. However early on this was mostly just water from the river-side of the Canal head; most of the area along the Canal in back of Gentilly Ridge remained cypress swamp with a few cow-pastures subject to periodic flooding.

In the early 20th century the old "London Avenue Machine" steam-pump at the head of the Canal was replaced with a more efficient system of high capacity pumps designed by A. Baldwin Wood. Residential development of the areas along the Canal in the Gentilly neighborhood (except along the highest ground along Gentilly Road itself) did not begin until after Wood's improved drainage system was operational. Dillard University was established beside the Canal.

In the 1930s construction of levees along Lake Pontchartrain and the Paris Avenue Canal improved drainage further back along the Canal's borders. With additional lift pumps in place in 1945, the full length of land along the Canal all the way back to the lake was soon developed as residential neighborhoods.

A major project of upgrading the floodwalls and bridges along the Canal was begun in 1999.

The London Avenue Canal Levee and floodwall was breached during or shortly after Hurricane Katrina in late August of 2005. This breach contributed to the flooding of New Orleans. Some has speculated that were it not for the breachs most of western Gentilly may have been spared from major flooding.

The first major breach, on the west or upper (up-river) side of the canal was behind the homes around the 6100 block of Pratt Drive (about 1/2 block riverward from Robert E. Lee Avenue). A second breach, on the east or lower or down-river side of the canal behind the homes near the intersection of Wilton and Warrington Drives (a block back from Mirabeau Avenue.)

The U.S. Army Corps of Engineers began efforts to fill the breaches in September; More flooding flowed from the incompletely patched canal during Hurricane Rita the next month, but not enough extent to cause any damage that was not already left from Hurricane Katrina.

Examinations have shown that high water never topped the floodwalls; the flooding was due to engineering failure of the levees and floodwalls. Allegations of design flaws, shoddy construction, and use of inferior materials are being investigated.

Water continued to flow from seepage in the temporary levee in lower breach in sufficient quantity to cover nearby streets as late as the first week of January, 2006. That month the Army Corps of Engineers finished temporary repairs of the canal breaches; a project of more permanent repairs is underway.