The Missouri River is the longest river in North America.

It winds its way through seven states.

And as it snakes down through Montana and the Dakotas and into Nebraska and Iowa,

it's just this big drainage river of all of the snowpack, all of the moisture,

everything that happens in the upper Midwest, eventually comes down the Missouri.

Tony Messinger writes at the St. Louis Post-Dispatch.

That's where the river ends.

And every spring, when the snow melts, he looks upstream to see where all this water's going to go.

Over 300 river gauges are above flood stage as we speak.

This year, the water's gone everywhere.

Whole towns have been evacuated.

Roads are closed.

Nebraska estimates its agricultural industry is losing a million dollars a day.

Tony could have these communities that are just inundated with water.

Tony could have told you this was coming.

The Missouri River is dotted with dams and levees, mechanisms that redirect and manage the river's flow, slow the water down, speed it up.

Days ago, Tony started getting these alerts from the Army Corps of Engineers as they released more and more water like a faucet.

And they started at 20,000 cubic feet per second, and a few hours later they were at 50,000

cubic feet per second, and within 48 hours they were up to 100,000 cubic feet per second

of water rushing down. And they knew when they made that decision that they

were protecting flooding in some areas and making it worse in other areas. I mean, they had no choice.

I knew there was a problem. I knew this was going to be a massive deal, whether it made its way

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