Cracked beam forces emergency shutdown of northbound Lake Shore Drive at Randolph

The discovery of a cracked support beam below the Lake Shore Drive bridge near Randolph Street prompted a closure of northbound lanes between Monroe Street to Grand Avenue on Monday. No injuries or damage to vehicles were reported.

The unexpected closure will last at least until Tuesday afternoon as crews rush to complete emergency repairs and install a “shoring tower” beneath the damaged segment. Permanent repairs could take weeks to complete, according to officials.

Northbound vehicles were detoured at Randolph and Monroe, westbound to Columbus, northbound to Lower Wacker Drive and back to northbound Lake Shore Drive at Grand Avenue, according to an alert from the Office of Emergency Management and Communications (OEMC), first reported by the Chicago Tribune.

By Monday evening, the closure shifted north, allowing traffic to exit at Randolph and Wacker and travel northbound using Lower Lake Shore Drive to cross the river, according to the city.

Chicago’s New Deal-era Outer Drive Bridge was constructed between 1929 and 1937. The need for unforeseen repairs to the aging structure was cited by city officials as a contributing factor in the delay of the Navy Pier Flyover project. The cracked section was completed later, in 1986, when LSD’s infamous S-curve was realigned.

Update: Northbound Lake Shore Drive reopened at Randolph on Tuesday afternoon, according to Chicago’s OEMC.

• Closure of northbound Lake Shore Drive over Chicago River to hit afternoon rush [Chicago Tribune]