Blue-gray areas were flooded during one or more of the Missoula Floods

One More Glacial Lake and Megafloods


Glacial Lake Ahtna dominated Alaska’s southcentral region during the Ice Age. Utah’s massive Lake Bonneville triggered the Bonneville Flood. But both Lake Ahtna and Lake Bonneville, stupdendous flood events themselves, were mere pikeminnows in comparison to the sturgeon that was Glacial Lake Missoula, which was not only a bigger flood event but happened as many as 80…