Lake Shore Drive Bridge to close for testing Tuesday night

The Lake Shore Drive Bridge over the Chicago River will be closed overnight for testing to prepare for the spring boating season.

The upper and lower levels of the bridge will be closed from 11 p.m. Tuesday to 5 a.m Wednesday morning, according to a statement from the Chicago Department of Transportation.

Northbound traffic on Upper Lake Shore will be rerouted via Randolph Street, Lower Wacker Drive and Columbus Drive, CDOT said. Southbound traffic will be rerouted via Grand Avenue, Columbus and Monroe Street.

Drivers heading north on Lower Lake Shore will be detoured via Lower Wacker, Monroe Street and Columbus, according to CDOT. Southbound drivers will be rerouted along Grand, Columbus and Monroe.

The closure is part of CDOT’s annual testing of river bridges before the start of the spring boating season.

Every spring and fall, workers raise the movable bridges along the Main and South Branches of the river twice weekly — on Saturdays and Wednesdays — to accommodate recreational boats traveling to and from their storage yards.

During these “boat runs,” the bridges — all 27 between Ashland and Lake Shore Drive — are raised sequentially, typically one at a time. Each bridge lift takes an average of 8-12 minutes.