The Michigania Sea

The Michigania Sea is a combination of 4 of the Great lakes, Lake Huron, Lake Michigan, Lake Superior, and Lake Erie. The Michigania Sea defines the landscape of Michigania.

History
Post apocalypse, Survivalist scientists decided to change the names of the great lakes, seeing as how many of them were actually connected in some way. Instead, the new classification was a Sea, made up of four lakes. Since the Survivalist Empire trade and fishing have been the way of the sea.

The Seas also have a pirate problem, many companies have had to organize armed guards for long voyages.