July 4, 1929 Tsunami: Grand Haven, Michigan, United States

Grand Haven, July 4th, 1929; Storm passage early in day; 2 waves produced; 6-meter height; Swimmers swept off pier and beaches;10 dead (reference #13569)

On July 4, 1929, more than 45,000 people gathered at Grand Haven State Park to celebrate the national holiday with a day at the beach. An early morning storm spawned a seiche that kicked up large waves; one swept a 16-year-old Grand Rapids girl off the breakwater and into Lake Michigan, where she drowned. A second seiche swept across the lake about five hours later, unleashing a wall of water that lashed the Grand Haven beach with 20-foot waves and a powerful undertow that pulled nine more people to their deaths. "It was a quick and nasty sea," according to a U.S. Coast Guard captain at the scene, who was quoted in the Muskegon Chronicle the next day. "For a short squall, it was one of the worst I've ever seen." Seiches can slosh back and forth across the Great Lakes for hours, depending on the weather conditions. For that reason, the National Weather Service recommends that people use caution when swimming in the Great Lakes or venturing out onto piers before or after a squall line passes through. (reference #13570)