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The Quad-Cities is on target to exceed the record for the most consecutive days at or above major flood stage on the Mississippi River.

But don't expect to get back into a regular traffic routine when the floodwaters finally recede. Roads that have spent more than a month under water will have to be thoroughly inspected for damage, such as erosion, below-surface voids and major potholes.

The current record for most days at major flood stage hit in 2001 with 30 days. That flood exceeded the previous record from 1993 of 29 days.

"The current forecast has it breaking the record," said Alex Gibbs, a meteorologist with the National Weather Service, Quad-Cities. "It's a drawn-out fall."

And the potentially bad news keeps coming: "Since we're staying up so high so long, the rain could have a big impact — even a second crest in another month," Gibbs said. "Snow up north still has to come down, and they're getting rain on top of the snow."

Flood stage on the Mississippi River in the Quad-Cities is 15 feet, and major flood stage is 18 feet. At that level, River Drive in Davenport and Moline are affected, and most of LeClaire Park is buried in floodwater.

For those in local Public Works departments, sustained floodwaters ultimately mean cleaning up a muddy mess. But they first have to make sure the long-covered roads and bike paths are safe.

"The roadways are inspected for any signs of damage or indications that the pressure of the floodwater found a path under the pavement," said Brian Schadt, Davenport's city engineer. "These areas would be fixed accordingly.

"Unfortunately, as floodwaters rise, they do create pressure points on the existing infrastructure. If the waters do move in the subsurface, they can create voids or damage pipe and structures.

"If the pressure builds underneath the pavement, it can cause the surface to distort or break. Depending on the road surface, the flood may exacerbate potholes, causing more damage."

In Moline, the popular Ben Butterworth Parkway has sustained damage in the past when floodwaters stood too long on the path surfaces and along the shoreline.

"We do have a couple of locations on the path that are relatively close to the bank of the river," said Rodd Schick, Moline's municipal services general manager. "In the past there has been erosion up to the path, which has required some repairs.

"The really big issue with the continuous flooding is that the banks erode along the entire parkway. Then we need to have a contractor bring in soil to replace what was washed away and then install additional large rock to protect it."

Formerly flooded roadways will remain closed until city crews have time to fully inspect and assess the damage.

"We have to make sure that nothing has washed out from underneath them," Schick said. "So the big message is that things won’t open as soon as the water recedes. We have to inspect and repair things first to ensure the public’s safety."

Added Schadt: "We inspect the storm inlets to see if anything has washed away from the backsides. We inspect all of the joints/seams to see if tar is still sealing them and, if not, if there are any cavities. We look for any sections that have an elevation change or if it they are not level.

"As part of this inspection, we’re planning to reseal all of the joints/seams with tar."

Some areas of the city could sustain damage, even though they are well out of the floodwaters, Schadt said.

Areas that are part of detour routes get more traffic than usual, and damage can result from the heavier-than-normal load.

"Roadways are designed based on their functional classification," he said. "If a roadway is intended to be a freight route or carry a large volume of traffic, the pavement section is constructed accordingly.

"Where we would typically see issues is if freight and other heavy traffic begin using residential or other local roads in lieu of normal truck routes."

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