Sinking Missouri River threatens levees, bridges

The Missouri River is sinking.

As engineers try to figure out why, the phenomenon threatens to damage billions of dollars in property, weaken levees and bridges and expose navigation hazards such as sunken piers and underwater pipelines.

The problem is this: Parts of the nation’s longest river are losing elevation. The so-called
“degradation” process is not affecting the amount of water in the channel, but the water is physically lower on the Earth because the river bottom is washing away.

The water depth is not changing, and the situation is nearly imperceptible from shore.
“Part of the whole problem is it’s not visible,” said John Grothaus, chief of planning for the Army Corps of Engineers in Kansas City, where the river bed has dropped by about 12 feet over the last 50 years.

Degradation has been observed in waterways across the country, but many scientists are focused on the Missouri River, which is used for shipping many agricultural products and provides drinking water to many cities.