Outbound Dan Ryan ramp to Stevenson down to one lane until at least Oct. 9

Fire damage will constrict traffic on a ramp merging southbound lanes of Chicago’s two busiest expressways for more than a week, state Department of Transportation officials said Friday.

A rubbish fire Wednesday evening did “extensive damage” to steel beams under the right lanes of the outbound ramp of the Dan Ryan Expressway that feeds into outbound lanes of the Stevenson Expressway. A single lane — on the left — will remain open while crews undertake temporary repairs and a more in-depth inspection of the damage.

Some 25,000 cars traverse the ramp, according to IDOT spokeswoman Maria Castenada.

Temporary repairs are expected to finish in time for the weekday morning rush hour on Monday, Oct. 10. More extensive repairs will require another six to eight months to complete, according to a news release from IDOT. That release did not provide details on whether those more extensive repairs also would require further lane restrictions.

In the meantime, motorists are being rerouted east toward DuSable Lake Shore Drive, where they will exit at King Drive to get on the outbound Stevenson Expressway, Castaneda said.

Chicago Fire Department rigs responded to a report of a fire around 8 p.m. Wednesday, quickly extinguished the blaze and left the scene without incident, CFD spokesman Larry Langford said. No further investigation of the fire is anticipated.