If you live near a river in Illinois, keep an eye on the water levels over the next few days. The National Weather Service is warning that ice jams could cause sudden flooding in some areas as temperatures fluctuate.
Right now, rivers that were frozen solid just days ago are starting to thaw and break apart. As big chunks of ice drift downstream, there’s a risk that they’ll get stuck in narrow spots like bends, bridges, or dams, blocking the river’s flow.
That’s when things can get dangerous. If water can’t move past an ice jam, it rises quickly, flooding nearby areas. And if that jam suddenly breaks loose, all that backed-up water rushes forward at once, creating a flash flood risk.
If you live near a river, this is a good time to stay alert and be prepared.
Why Is This Happening?
After weeks of freezing weather, ice built up on rivers across Illinois. Now that temperatures are warming up, that ice is cracking and breaking apart, sending chunks downstream.
That may not sound like a big deal, but if those ice chunks pile up and block the river, it can lead to:
- Flooding upstream as water backs up behind the jam.
- Flash flooding downstream if the jam suddenly gives way and releases all that water at once.
Which Areas Are at Risk?
Ice jams have already been reported in some spots, and more could develop in:
- Kankakee River – Ice buildup near Momence has already triggered a Flood Watch.
- Fox River – Ice is accumulating near Algonquin, and water levels could rise quickly.
- Des Plaines River – Narrow sections of the river are especially prone to sudden ice jams.
- Rock River – Large chunks of ice have been spotted moving downstream.
What’s the Worst-Case Scenario?
Flooded Homes & Roads – If an ice jam blocks the river, water levels can rise fast, flooding homes, roads, and low-lying areas.
Flash Flooding – If the jam suddenly breaks, all that backed-up water rushes downstream at once, catching people off guard.
Road Closures & Damage – If flooding worsens, bridges, roads, and riverbanks could take a beating from fast-moving water and ice chunks.
How to Stay Safe
✔ Stay Informed – Keep up with local news and weather alerts for updates on river conditions.
✔ Have a Flood Plan – If you live near a river, know where you’ll go if you need to move to higher ground quickly.
✔ Move Valuables Off the Floor – If you’re in a flood-prone area, keep important items and documents stored higher up in case water rises.
✔ Avoid Frozen Rivers & Flooded Areas – Ice jams can break apart without warning, making it extremely dangerous to be near the water.
✔ Never Drive Through Flooded Roads – It only takes 6 inches of moving water to knock you off your feet and a foot of water to sweep away a car. If a road is flooded, turn around—don’t risk it.
The Bottom Line
Ice jams can form and break apart suddenly, causing dangerous, fast-moving floods. Right now, rivers like the Kankakee, Fox, Des Plaines, and Rock Rivers are at the highest risk.
Even if everything looks fine now, that can change in an instant. If you live near a river, stay alert, take flood warnings seriously, and don’t wait until it’s too late to prepare.
