The canal allowed steamboats and sailing ships on the Great Lakes to connect to the Mississippi River.
To accommodate rapid population growth and demand for better sanitation, the city improved its infrastructure.
This project began with the construction and improvement of the Illinois and Michigan Canal, and was completed with the Chicago Sanitary and Ship Canal that connects to the Illinois River, which flows into the Mississippi River.
The city grew significantly in size and population by incorporating many neighboring townships between 18, with the largest annexation happening in 1889, with five townships joining the city, including the Hyde Park Township, which now comprises most of the South Side of Chicago and the far southeast of Chicago, and the Jefferson Township, which now makes up most of Chicago's Northwest Side.
While elevating Chicago, and at first improving the city's health, the untreated sewage and industrial waste now flowed into the Chicago River, and subsequently into Lake Michigan, polluting the city's primary freshwater source.
The city responded by tunneling two miles (3.2 km) out into Lake Michigan to newly built water cribs.