Hydrologists say ice jams unlikely but still possible

BISMARCK, N.D. (KFYR) - If you’re a Bismarck native, you might recall the ice jam of 2009.

The potential for flooding was so drastic, the National Guard teamed up with detonation experts to demolish the jam on the south side of the city.

While experts say ice jams aren’t as likely this year, there’s still a chance because ice jams are not mathematically predictable.

Residents might be aware the Missouri River can be a problem child at its worst.

In 1953, an ice jam created a massive flood — causing half a million cubic feet of water per second to come rushing through Bismarck.

Hydrologist Alan Schlag says ice jams are created in the area when a tributary dumps its ice into the Missouri river.

If the Missouri has its own ice load, the ice can jam up, causing water to rise.

“One of the worst things that comes with an ice jam is when the ice blocks the river channel, we see flash flooding along that portion of the river in mere hours. The river can rise maybe eight feet in six hours,” said National Weather Service Hydrologist Alan Schlag.

Schlag says at this point, the weather can create one of two scenarios.

The first is for the weather to turn from cold to warm within a couple of days. Pair that with rain, and Schlag says that’s the perfect storm for ice jams.

Schlag says we want scenario two, which would be a slow, gentle melt to allow the Missouri to clean up the ice and avoid any jams.

Schlag says it’s important to recognize the potential — especially if you live along the river.

Schlag says to get your belongings out of the danger zone. Then, if an ice jam were to occur and cause flooding, the only thing you’d need to remove is yourself.

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