More than 1,000 people participated in the unsanctioned marine event known as the Port Huron Float Down Aug. 16, 2015, during which participants gathered at Lighthouse Beach in Port Huron, Mich., to float 7.5 miles down the St. Clair River on the border of the U.S. and Canada in inflatable and makeshift rafts. The event has no official organizer and poses significant and unusual hazards given the fast-moving current, large number of participants, lack of life jackets, alcohol consumption, potentially challenging weather conditions, water temperature and limited rescue resources. (U.S. Coast Guard photo by Chief Petty Officer Lauren Jorgensen)