It's History

Chicago's Forgotten Lake Tunnels, Cribs, and Waterworks (8x28)

:

The History of Chicago's waterworks is jam-packed with some of the most remarkable examples of human innovation, from the miles of tunnels built directly under lake Michigan to the artificial islands known as water cribs, the lifting of the entire city, and the reversal of the Chicago River. Although these feet of engineering are impressive, probably nothing will compete with the monumental deep tunnel project that has been unfolding for the past few decades.