Why were the Great Lakes and Mississippi watersheds connected in the first place?
In the late 1800’s the city of Chicago had a major problem with discharge of sewage into the Chicago River polluting the river and then Lake Michigan. Chicago also used Lake Michigan as the source for its municipal water supply which was getting contaminated. In 1900 the flow of the Chicago River was reversed to flow from Lake Michigan to the Illinois River and then on to the Mississippi River. The Chicago Sanitary & Shipping Canal was created to reverse the flow and make the connection between the two rivers. Daily, 2.1 billion gallons of water from Lake Michigan now flows out through the Chicago River.
