The Mississippi and Ohio Rivers converge near the small town of Cairo, Illinois. Just below this confluence point, the river enters a section where its path is very straight and narrow. This section of river, which marks the border between Kentucky and Missouri, can handle moderate flood waters of either the Mississippi or the Ohio, but not both. In the event that both rivers would flood, or a monumental flood would occur, the combined river flows would flood vast areas of these two states.

To protect against this occurrence, the US Army Corps of Engineers installed a relief valve in the river system. A low spot was built in the levee at Birds Point, which is just downriver from Cairo. In the event of a large flood, the waters would overtop this levee, causing it to fail. When it fails, up to one-fifth of the river flow would be diverted through the New Madrid Floodway. A 1,500 foot wide gap in the levee system just north of New Madrid would allow the water in the floodway to rejoin the Mississippi River. The result is that a large fraction of Mississippi and Ohio River flood water would bypass the narrow section of the river, likely sparing much of the adjacent farming regions from flooding.

There turns out to be two glitches in this plan. First, when the floodway was first used, the levee at Birds Point refused to fail, so the US Army was forced to blow the levee with explosives. Second, the outlet near New Madrid allows water from smaller floods to flow backwards into the floodway, needlessly flooding the farmland in the floodway area.

The US Army Corps of Engineers has a plan to fix these issues. First, the levee at Birds Point would be converted into a fuse plug. That is, pipes would be installed in the levee to allow explosives to be pumped in and detonated when needed. This allows the US Army Corps of Engineers to pick the time when the floodway is opened rather than leaving it to chance. Second, the gap in the levees near New Madrid would be closed off. This would prevent the backflow floods. It would also prevent the water from exiting the floodway naturally. The plan is to install two large pumping stations to pump out the floodway.

This plan is not without its critics. They argue that nature should be allowed to do its job without human intervention. They also see the backflow flooding from the outlet gap as beneficial to the wetlands rather than the annual destruction of large areas of farmland.