The Taum Sauk Dam’s Upper Reservoir fails, sending huge volumes of water racing down Proffit Mountain. Miraculously, no one died and only four people suffered injuries, though the catastrophic event wiped out nearly 300 acres of Johnson’s Shut-Ins State Park and caused more than $1 billion in damage, according to a history from the Association of State Dam Safety Officials. The image shows the reservoir being reconstructed in 2009. 

Photo credit: Wikimedia Commons.