CHICAGO (STMW) — Drivers approaching the Jane Byrne Interchange — now one of the nation’s worst bottlenecks — will face a spaghetti bowl of detours and reduced lanes for more than a year after construction begins March 7 on a flyover bridge.

Needing a stiff dose of patience until at least the summer of 2016 will be:

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— South Siders taking the Dan Ryan Expressway (Interstate 90/94) into the Loop;

— Folks traveling back and forth from west of the city to downtown on the Stevenson Expressway (I-55);

— Drivers switching from the inbound Ryan to the outbound Eisenhower Expressway (I-290).

They will soon face ramp lane or road lane reductions and even some detours during the next phase of the $475 million overhaul of the interchange — a connection point crossed by 400,000 drivers daily.

But by far, experts say, the biggest logjam will hit over four weekends sometime this summer or fall. That’s when workers will install beams of the long-awaited flyover that will connect the inbound Ryan with the outbound Eisenhower. The exact weekends have not yet been identified.

During the worst two of those weekends, all lanes of the Eisenhower on either side of the Ryan will be shut down, and 1-mile to nearly 2-mile sections of the Ryan approaching or leaving downtown will be limited to one lane in each direction, Illinois Department of Transportation officials say.

“It won’t be pretty,” said Tom Kaeser, a former senior traffic engineer for the Chicago Department of Transportation.

“I’m sure that IDOT and CDOT will publicize this a lot and urge everyone to avoid using these roadways, as they did during the Ohio-Ontario ramp removal work along the Kennedy” Expressway in June 2014.

“Anyone who is aware of these closures and still tries to drive through will have only themselves to blame if they get stuck in traffic,” Kaeser said.

IDOT is still working with the city to schedule those four weekends of work, IDOT spokeswoman Carson Quinn said. Chicago is buzzing with festivals in July, August and even September, when the Chicago Bears’ regular season starts.

Also hard hit may be fans of the White Sox and Bulls and Bears because their stadiums are close to the work zone.

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Over the first two weekends of work, the inbound Ryan will be reduced to one lane, tentatively, from Canalport to Van Buren — or for about 15 blocks; the outbound Ryan will be narrowed to one lane from roughly Lake Street to Harrison — or for about eight blocks.

Those same two weekends, the outbound Eisenhower will be completely inaccessible via Congress Parkway, and inbound travelers will have to exit the Eisenhower before the Ryan, possibly around Ashland, Quinn said.

On the final two weekends, only outbound Eisenhower and outbound Ryan traffic will face closures or lane reductions.

The less severe changes that begin March 7 will stretch on “until summer 2016,” according to IDOT.

That means for about 16 months, South Side travelers heading from the Ryan into the Loop will hit ramp detour signs starting at Roosevelt. Drivers moving from the Stevenson to the Ryan, or vice versa, will deal with lane reductions on ramps and roadways.

The heavily traveled inbound Ryan connection with the Eisenhower will see drivers directed to a temporary road.

“Since we are shifting the inbound Dan Ryan lanes toward the median using a little tighter lanes, we will build a small runaround or connection to connect the outer lane of the inbound Ryan to the existing flyover, which [will continue] to be used until the new flyover is built,’’ Quinn said in an emailed statement.

“We are talking about a couple of hundred feet of roadway to complete the gap and allow traffic to exit safely.”

When the misery ends, the Jane Byrne Interchange flyover will replace the existing single-lane ramp from the inbound Ryan to the outbound Eisenhower with a milelong ramp, starting at Roosevelt, and a two-lane bridge.

Better yet, IDOT officials say, it should reduce traffic delays by at least 50 percent.

More information on the four-year project, including a live-stream of construction work, can be found at

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(Source: Sun-Times Media Wire © Chicago Sun-Times 2015. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)