The solution to chronic gridlock on the Circle Interchange is up in the air, both literally and figuratively.
For one, Illinois Department of Transportation planners are proposing several alternatives to ease congestion on the notorious chokepoint and a final design won't be set for months.
Secondly, among the options are flyovers, elevated highways that lift traffic as it merges onto other highways as opposed to ground level ramps.
IDOT engineers held a forum Thursday for the public to comment on design scenarios for the estimated $375 million construction project.
The Circle Interchange was built throughout the 1950s and 1960s. The outdated structure handles about 300,000 vehicles daily that weave between the Dan Ryan, Kennedy and Eisenhower expressways as well as Congress Parkway.
The high volume of traffic makes for myriad logjams and crashes, IDOT officials noted. Among the problems:
• Drivers heading from the northbound Dan Ryan onto the westbound Eisenhower or eastbound Congress Parkway crawl along in two dysfunctional lanes before reaching the exits. Sneaky motorists heading for the Eisenhower will exacerbate the gridlock by sticking to the faster-moving outside lane leading to Congress Parkway, then at the last moment cutting into the inside Eisenhower lane.
• Faster vehicles from the southbound Kennedy and westbound Congress Parkway converge with slower traffic from the northbound Dan Ryan at the start of the westbound Eisenhower, leading to collisions.
• Ramps shifting traffic among the expressways are over capacity, as are the mainline Kennedy and Dan Ryan.
The solution will be adding capacity to the ramps of the three highways and Congress Parkway as well as to the mainline Kennedy and Dan Ryan. Some of the more elaborate scenarios involve a two-lane flyover from westbound Congress to the southbound Dan Ryan or a two-lane flyover from the northbound Dan Ryan to the westbound Eisenhower.
"We're starting with a blank slate," IDOT project manager Steve Schilke said. "It's an engineering enigma.
"Some (of the alternatives) are a lot simpler, others more complicated. Right now, we're putting these through an evaluation screening."
All the construction can be accomplished within IDOT right of way and no properties will have to be acquired, Schilke said. However, as the project will encroach on nearby condominiums and the University of Illinois at Chicago campus, the state is working with those neighborhoods.
When construction starts it could be messy, depending whether workers build on existing highway or construct new roads above, officials said.
The state is paying up to $40 million for engineering of the project, but the $375 million construction is not funded. The bulk of the money is expected to come from the federal government, officials said.
So once the improvements are completed, does this guarantee drivers won't crawl along the eastbound Ike when they merge with the southbound Dan Ryan at 6 p.m. before a Sox home game?
"There still will be traffic -- the delay will be less," Schilke said.
Public comments on the initial plans will be accepted until Sept. 13. To comment, go to, www.circleinterchange.org/stay_informed/.