Vehicles drive past a sign showing a 60 mph speed limit while traveling south into Illinois on Interstate 90/39 on Tuesday.


The state Department of Transportation is reducing the speed limit from 70 to 60 mph on parts of Interstate 90/39 that are under construction this spring between the state line and Madison.

DOT spokesman Steve Theisen said the DOT already has placed signs along I-90/39 between the state line and Cranston Road in Beloit, so the 60 mph limit is already in effect in that area.

He said the agency tentatively plans to post the same reduced speed limit within Janesville-area work zones by late next week.

Theisen said the DOT will announce later this week when the speed limit reduction will take effect through Janesville.

The 60 mph zone signs will be posted on I-90/39 between Avalon Road and Highway 14, where the DOT is working on expanding the southbound lanes, and from Highway 14 north to Kennedy Road, where it is getting ready to replace the Highway 14 and Highway 26 interchanges.

Along with the speed limit reduction, motorists heading northbound through Janesville should expect a lane changeover near the Highway 14 interchange that will route both northbound and southbound traffic onto the southbound side of I-90/39, the DOT said.

The only local exception to the new speed limit is the span between the Rock River bridge at Newville and the Highway 51 interchange at Stoughton, the DOT said.

In that section, the speed limit will remain 70 mph.

As heavy construction picks up along the corridor, Theisen said the DOT is asking the motorists to pay attention to signs that show lane shifts and other details about the expansion work.

The Wisconsin State Patrol plans to enforce the new speed limit with additional patrols and aerial monitoring, the DOT said. Fines for speeding double in work zones, and it’s also against state law to use a cellphone while driving through a work zone.

Theisen said the latter should be people’s main takeaway.

“Put down the phones and focus on the road ahead,” he said.