By the 1920s, the City of Chicago had developed an extensive water system which covered most of its territory. In addition, dozens of suburban systems had emerged to serve settlements along rail lines out from the city center. This 1988 diagram shows the process by which the city draws water from intake cribs miles out in Lake Michigan, purifies the water, and sends it out around the city to pumping stations, which then pump water to individual neighborhoods and houses.

Creator: City of Chicago, Department of Water
Source: Chicago Historical Society (ICHi-37397)