U.S. Army Corps Flood Failures on Mississippi Demand New Vision
I stood at the edge of the Mississippi in New Orleans last May, the river so high that a fat wake would have sent swirling waters over the levee’s edge. That day the U.S. Army Corps of Engineers began opening the Morganza Spillway above Baton Rouge, Louisiana, routing water from the swollen Mississippi down the Atchafalaya River. To keep the Mississippi from overtopping levees in Baton Rouge and New Orleans, the diversion inundated farms and prime oyster-rich inlets. In Missouri, just two weeks earlier, the Corps had blown out more than two miles of levee at Birds Point to vent floodwaters that threatened Cairo, Illinois. A fifth of the river’s flow quickly covered 130,000 acres of farmland. The record-breaking spring floods “tested the limits of the system,” said Paul Harrison, senior director for Mississippi River and East Coast at the Environmental Defense Fund. He said the Army Corps, which has managed the river’s flow since 1824, “wants to continue to invest in the old system rather than look at these events as an opportunity to create a 21st-century system.”
Similar criticism has come from Congress, flood-plain managers, and other major interests, and more people are daring to say that the river defenses need to be redesigned from top to bottom.
Is the Corps up to the task? It’s too soon to forgive the army for the colossal levee failures that brought New Orleans to its knees. The future some envision is breathtakingly audacious. Instead of the dull, domesticated mass of mud-laden water that today runs largely in straight channels between mown-grass levees, the river would run free, winding in wide, lazy oxbows, around ponds and marshlands covered with flocks of waterfowl. Forest and wetland buffers would filter out fertilizers and pesticides that are today sluiced at high speed to the Gulf of Mexico. There, they plunge off the edge of the continental shelf and form a deepwater dead zone that threatens fisheries. This year, it covers 6,800 square miles. Major General Michael J. Walsh commands the Mississippi River Valley Division in Vicksburg. I asked him by phone whether the flood protections are up to the task. “Historic? Defining? Epic? We’ve been looking for the right adjective to describe this year’s flooding,” he said. “We used every element of the flood-control system, but my hydraulic engineers are reporting that we used about 85 percent of the system’s design capacity. We still had a reserve.” He added that the Corps increasingly works with the river’s natural features to slow floodwaters.
Others aren’t as sanguine. Environmental Defense and several other groups are tackling a vexing problem: the need to rebuild coastal Louisiana marshes that have rapidly receded, in part because they are denied sediments the river supplied by overflowing its banks. Last year I was guided into the river’s lower reaches by Ben Weber of the National Wildlife Federation’s Coastal Louisiana program and two local officials of the National Audubon Society, Paul Kemp and Bruce Reid. Our motorboat departed from Venice, Louisiana, steering past net-covered fishing boats and oil rig staging yards. As we reached Southwest Pass, the shipping channel into the Gulf, I was surprised to find the river demarcated from the sea only by a rock embankment and a thin line of grasses. With prehistoric-looking, and aptly named, Magnificent Frigatebirds circling overhead, massive, rumbling dredgers labored 24 hours a day to keep the navigation channel open. The river is trying to short circuit the delta, but the dredging keeps it on the course the Army Corps has set.
The delta is falling apart, according to my guides, and the disappearing coastal marshes harm the fishing industry and leave inland cities like New Orleans more vulnerable to hurricanes. They see the Corps efforts as unsustainable in the long term. Harrison and his colleagues have been raising money to sponsor a competition that would invite teams of experts to redesign the delta so that it reconciles the needs of the environment, flood control, and navigation. In architecture, competitions have led to great buildings, like the Sydney Opera House. Asked about the competition, Walsh said, “We would certainly add any of their ideas to our study matrix.” Walsh advocates “a 200-year vision,” one that covers the entire watershed because flooding tributaries contributed to the near record flows of the Mississippi. That sounds impressive, but the vision today comprises a list of aspirations covering a single page.
‘We Know Best’
It doesn’t take a stand on the many battles among competing interests that must be fought, and it certainly doesn’t identify how many billions it would cost or where the money would come from. And that suggests Corps “we know best” business as usual. It’s not good enough. The river’s outsize contribution to the U.S. economy and environment makes fleshing out that vision an urgent task. A series of design competitions could drive innovation and help find common ground. Fabled 100-year floods seem to show up every few years now.
James S. Russell in New York at firstname.lastname@example.org.