Moline will do everything it can to keep traffic moving as smoothly as possible on Monday when the detour for the Interstate 74 bridge construction begins, but Mayor Stephanie Acri is worried.
The current plan calls for Iowa-bound traffic to leave the interstate at 19th Street, traveling 19th to River Drive in the downtown and then making its way through three stoplights to get onto the bridge to Iowa. Illinois-bound traffic would be unaffected.
Delays of up to 30 minutes and a backup of 317 vehicles (1.5 miles) are considered acceptable according to plans by the Federal Highway Administration, she said.
But she believes the plan makes two assumptions that don't accurately reflect the city's true traffic pattern, and this could lead to gridlock, particularly at mid-day.
First, the calculations don't take into account that sometimes Iowa Interstate Railroad trains actually stop and, second, the calculations discount additional traffic from the Taxslayer Center when there are daytime events that can put an additional 500 cars or more into the downtown, Acri said.
What Acri is proposing instead — and argued before transportation officials in a meeting Tuesday in Springfield — is to allow Iowa-bound traffic to stay on the interstate, but move it over to one lane of the Illinois-bound side.
In other words, make the Illinois-bound interstate a two-way between the bridge and Avenue of the Cities.
Traffic over the bridge itself would remain two lanes Illinois-bound, while the Iowa-bound would be reduced to one, the same as with the current plan.
Acri's plan would avoid train delays entirely.
Why is all this happening anyway?
The reason for the detour is that, in order to speed up bridge construction to a 3½-year time frame, workers need to begin now in building the Iowa-bound lanes between Avenue of the Cities and the bridge.
Acri said the detour going into effect Monday was based on community stakeholder meetings held in 2013. But around December of 2018, Acri said she began to realize that actual traffic might be different than assumed.
The city conducted a 10-day study at the end of February and first part of March in which it recorded the time that train gates were down. "What we found is that they were down significantly longer than the seven minutes the Federal Highway Administration plan assumes," Acri said.
Over the 10 days, there were 50 instances in which the time exceeded seven minutes.
"It's not every time, but it is frequently enough that it could cause gridlock, or 'catastrophic congestion,' and that causes problems with cross-traffic," she said. Between 11-13 trains travel through the downtown daily.
Acri said Iowa and Illinois department of transportation officials are agreeable to her plan, but federal officials aren't convinced. One of their concerns is that the plan would reduce speeds of Illinois-bound interstate traffic and this wasn't accounted for in their public hearings, Acri said.
In order to adopt another plan such as Acri's that restricts the flow of an interstate highway system, additional hearings would have to be held and studies made.
That would take at least a month, she said.
"I couldn't get them to trigger the public meeting (portion). They were not willing to commit to that yet." But she said she did convince officials to at least begin planning.
In order to make any modifications, the state departments of transportation would have to revisit the approved traffic management plan which was developed and committed to in the environmental process, federal officials said, adding the Federal Highway Administration is committed to working with the Quad-Cities, the state DOTs, and the public to ensure all concerns are addressed.
Representatives of the Illinois and Iowa departments of transportation could not be reached for comment on Acri's plan.
Meantime, the detour going into effect Monday could last as long as a year, or as long as it takes to finish the Illinois-bound span over the river. At one time, that was expected to be this fall.
But "the timeline has been delayed," Acri said. "It appears (construction) will go through the winter and be ready in spring (of 2020)."
"All this being said, I hope we are wrong," Acri said of potential gridlock with the detour. "I hope the original assumptions are right."
Just in case, the city will have employees available to help move traffic after a train delay. This is similar to what the city did to keep traffic moving during portions of the John Deere Expressway construction.