The U.S. Coast Guard will enforce a temporary safety zone across the entire width of the South Branch of the Chicago River on October 20, 2026, to accommodate bridge repair work by the Chicago Department of Transportation. The closure applies between mile marker 325.4 and mile marker 325.5 for the assembly of the Lake Street Bridge.
Enforcement Windows and Alternate Dates
The safety zone regulation detailed in 33 CFR 165.930(a)(3) takes effect from 6:00 a.m. through 6:00 p.m. on October 20, 2026. The Coast Guard established alternate inclement weather dates and times spanning four separate days. Those backup enforcement periods run from 6:00 a.m. through 6:00 p.m. on October 18, October 19, October 21, and October 22, 2026.
During these active windows, entry into, transiting, mooring, laying-up, or anchoring within the designated zone is strictly prohibited. Spanning the entire breadth of the waterway, these measures take effect at Mile Marker 325.5 and terminate at the Randolph Street bridge located at Mile Marker 325.4. N.R. Downend, Commander, U.S. Coast Guard, Acting Captain of the Port, Lake Michigan, noted that the action is being taken to provide for the safety of life on the navigable waterway during the assembly of the Lake Street Bridge.
Maritime Directives and Enforcement Protocols
Under 33 CFR 165.930(c)(1), the Captain of the Port Lake Michigan holds the authority to enforce the safety zone in whole, in segments, or through any combination of segments, as well as suspend enforcement of specific segments as needed. Any vessel or person granted explicit authorization by the COTP Lake Michigan or a designated on-scene representative must obey all lawful orders.
Vessels hailed by the Coast Guard via siren, radio, flashing light, or other signaling means must proceed precisely as directed. Operators may reach the COTP Lake Michigan through the Coast Guard Sector Lake Michigan Command Center at (833) 900-2247, while on-scene representatives monitor VHF-FM Channel 16. In addition to publication in the Federal Register, the Coast Guard distributes enforcement notices to the maritime community using Broadcast Notices to Mariners.
