The Coast Guard is establishing a temporary safety zone for the Missouri River at mile markers (MM) 19 through 20. The safety zone is needed to protect personnel, vessels, and the marine environment from potential hazards created by a power line wire crossing near Florissant, MO. Entry of vessels or persons into this zone is prohibited unless specifically authorized by the Captain of the Port, Sector Upper Mississippi River.
Source: Federal Register USCG
Link: Safety Zone; Missouri River Mile Markers 19-20 Florissant, MO