In the early 19th Century Chicago barely existed, by the the late 1840s it was growing rapidly.

With no sewage system it had numerous issues with disease, and being level with Lake Michigan there was no way to build a traditional sewer system.

The solution was to raise Chicago up to fourteen feet in places, and then later to reverse the Chicago river. 

This episode covers all this and more!

Before and after image for Chicago River reversal: https://chicagoriverstories.files.wordpress.com/2016/03/canal_image.jpg?w=640