Work will begin Friday night on Chicago's first two-way bike route with traffic signals.
The Loop's north-south protected route will run on Dearborn Street from Polk to Kinzie streets.
"The Dearborn Street barrier-protected bike lanes will provide bicyclists with a safe and comfortable route, making a key connection for people who commute via bicycle through the heart of the Loop," Chicago Department of Transportation Commissioner Gabe Klein said in a news release.
Crews will begin striping the roadway this weekend so the bike lanes can officially open by mid-December weather permitting, according to the release.
That means traffic lanes on Dearborn Street will be closed and parking will be prohibited on the west side of the street over the weekend.
On Dearborn, the west curb lane and western-most travel lane will be closed between Polk and Madison streets on Friday night and Saturday and between Madison and Kinzie streets on Saturday night and Sunday.
One traffic lane for cars will be eliminated on Dearborn Street between Polk Street and Wacker Drive to make way for the protected bike lane, the city said.
Dearborn will stay a one-way street for cars but will be a two-way street for cyclists for the 1.15-mile stretch.
Cyclists riding southbound will be adjacent to the west curb and bicycles heading northbound will go between the southbound cyclists and parked cars. Drivers will see new left-turn lanes and left-turn arrows at westbound cross streets.
It's a project lauded by the Active Transportation Alliance.
"Protected bike lanes create a more organized traffic flow that is safer for everyone, whether you are walking, biking or driving a car. This is especially important in the congested Loop," said Ron Burke, alliance executive director, in a news release.
Meanwhile, the city's first protected bike lane on Kinzie Street between Milwaukee Avenue and Wells Street, which opened in July 2011, could be relocated to Grand Avenue at the developer's expense when construction begins on the proposed Wolf Point project.
The proposed project has been rescheduled to go before the Chicago Plan Commission on Dec. 20.
"Active Trans believes Grand Avenue could be a great alternative route, as long as it allows for protected bike lanes accommodating two-way bike traffic between Milwaukee Avenue and the planned protected bike lane on Dearborn Street, and as long as the Grand Avenue bikeway is completed before the Kinzie bikeway is removed," the alliance posted on their web site.
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