Uneven exit built so long ago reasons why unknown

Q. Do you know why the southbound lanes of Route 83 exiting onto Lake Street and I-290 are not set up the same way as the northbound lanes? Of the three lanes going northbound, the right lane turns into an exit-only lane, while the center and left lanes continue north as Route 83. For the three southbound lanes, the right lane branches off to the right as an exit, but it also continues as a straight lane for southbound Route 83. At the same time, the left lane ends quickly, and mergers into the center lane. I have driven this route for many years and cannot understand why the right lane can't be an exit-only lane with center and left lanes continuing straight, just like on the northbound side. The left-lane merge into the center lane is where many accidents almost occur, in my experience. The cement roadway is already there on southbound Route 83, so the pavement only needs to be re-striped.

--K. K.

A. Both Jason Salley, acting geometrics unit head in the Illinois Department of Transportation Region 1 office in Schaumburg and Pete Harmet, bureau chief of programming in the same office said the project was engineered and built so long ago that none of the senior members of the office recall why the Route 83 exits were engineered the way they were.

"There may have been some right-of-way issues, or the department didn't feel there was a need for an exit-only lane on the southbound side," Salley said.

"It could have been any number of issues."

However, Salley said there hasn't been a need to change the configuration as far as accidents or traffic capacity.

"There haven't been a high frequency of serious accidents at the location within the last five years," Salley said. "It's not one of the top-five percent accident locations in our region."