The Straits of Mackinac connect Lake Huron and Lake Michigan, and divide Michigan's lower peninsula from its upper peninsula. But the gorgeous blue expanse of this part of the Great Lakes region is threatened by a danger lurking just beneath its surface: two degrading oil pipelines.Motherboard correspondent Spencer Chumbley went to Michigan to investigate the situation, and the research is alarming. If just one of the pipelines ruptured, it would result in a spill of 1.5 million gallons of oil—and that's if Enbridge, the company that owns them, is able to fix the pipeline immediately. UMich research scientist Dave Schwab says, "I can't imagine another place in the Great Lakes where it'd be more devastating to have an oil spill."