When you combine rushing water and an immovable object, something naturally has to give.
In this case, the immovable object lost. A section of Interstate 29 at the Hamburg exit is showing signs of succumbing to flood waters.
"It started undermining on the northbound lanes here," Hamburg Fire Chief Dan Sturm said. "So, what we have is erosion that's taking place on the sides on embankments. What the Department of Roads is trying to do now is bring up some heavy rock and rip rock the sides to keep the erosion down and keep it from undermining it like it did here."
This is the first serious structural damage along Interstate 29.
It could extend how long the interstate is closed.
That's bad news for travelers.
"There's major traffic flows through here every day...truck traffic, commerce so it has a big effect on everybody," Sturm said.
Those trucks are now filing through small towns like Hamburg on secondary roads.
Over-the-road trucker Dave Owen said more problems on the interstate means those detours will last longer.
"It's dangerous," he said. "It takes you out of your normal route and it can add an hour or two hours to your trip. It's rough, it really is."
"I think we have to just wait until the water's gone and they can get everything fixed."
The flooding imprint is visible on a now above water interstate.
That also will take time to clean up.
As for the structural damage on the interstate, Dan Sturm doesn't see it being a long term project.
"Once the water goes down, I believe they will be in here pretty quickly with whatever equipment they need to get this repair work done and to get this opened up," he said. "It's vital that they get this opened up again."
The scouring is at least 11 feet deep.
The piling that supports the structure is no longer embedded in the river bottom.
There is no way of knowing how extensive the damage is to that bridge and others until the water recedes.