Slide Show Photo courtesy of USACE The St. Louis District operated the emergency spillway at Wappapello Lake, Mo., for the first time since 1945. It caused about 40 ft of scouring into bedrock and washed out a section of road. Related Links: Corps Unveils Public National Levee Database Corps Pulls Out All the Stops To Cope With Rising River Corps of Engineers' List of 93 Mississippi Basin Critical Flood Repair Projects (PDF)
As time races toward fall floods and potential disaster along the Mississippi River and Tributaries System, the U.S. Army Corps of Engineers is at work on 10 projects—damaged by high water this past spring and summer—that the agency deems most critical to protect life and safety. This work is worth an estimated $75.8 million, but the Corps wants to focus on the long term. Both the public and policymakers should realize the U.S. faces increased risk to life, property, navigation and economics until the entire MR&T is restored to its pre-2011 strength—a feat that will require about $2 billion and take up to 15 years at current funding rates.
In Congress, both houses appear poised to fund about $1 billion in repairs, but the Supercommittee that is supposed to deliver a proposal by Thanksgiving to cut more than $1.2 trillion in spending over 10 years has yet to present its decisions, which will either make specific cuts or, if the committee cannot agree, trigger automatic across-the-board cuts.
"We want the states and the public who live behind these levees to know we currently do not have the funding to do these items on the list," says Scott Whitney, regional flood-risk manager for the Corps' Mississippi Valley Division. He says the levees performed, but they were stressed and now may not be able to handle even moderate flooding. He predicts "an extended period of risk for an extended period of time."
Since May, Corps engineers have compiled damage assessments and rough construction-cost estimates on the Mississippi and its subsystems from Cairo, Ill., to the Gulf of Mexico.
Further west, flooding in the Souris and Missouri rivers and tributaries continued through September, so assessments are just beginning there. Repairs won't be possible before winter. Thus, many of those areas will enter a new spring flood season with increased vulnerability.
"This is a big deal, and it's not going away any time soon," Whitney says. "Even with an endless pot of money, considering the magnitude and geographic scale of the damage, we can't turn that many projects that fast."
The Top 10
The Corps has identified 93 projects in the MR&T that comprise almost 3,000 damaged elements that should be repaired by the fall flood season. Estimates range from $704 million to $793 million. Of the 93, the Corps ranks only its top 10 priorities. The Corps cannot compile a complete, ranked list until it assesses damages in tributaries north of Cairo and weighs all MR&T needs against other priorities.
The top-priority project is to restore to a safe elevation the approximately four miles of levee blown up to operate the Birds Point-New Madrid floodway. The levee protects 133,000 acres of farmland. "We pulled funds from flood-response money to make the area safe by getting rid of debris and blast material and filling a 45-ft-deep scour hole that crossed a county road," Whitney says.
The Corps also built a temporary berm along the line of the previous levee but needs $18.5 million more to bring it to +55 ft by Nov. 30. That elevation is shy of the +62 ft design height. Whitney says the shortfall translates into a 6% chance of overtopping. "At +51 feet, it would have been exceeded 12 times over the past 20 years," he says.