The New International Encyclopædia/Chicago Drainage Canal

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CHICAGO DRAINAGE CANAL. This canal was built to connect the west branch of the south fork of the Chicago River (q.v.) with the Des Plaines River, one of the head streams of the Illinois River, under such conditions that the water flows from Lake Michigan, through the Chicago River and the canal, into the Des Plaines River, thus reversing the direction of flow of the Chicago River. The object of the canal is to divert to the Illinois River the sewage of Chicago, which had been previously discharged into Lake Michigan. The engineering difficulties were peculiar, and aroused much professional and general interest. Work was begun on the canal on September 3, 1892, and it was formally opened on January 28, 1900. The canal proper begins on the west fork of the south branch of the Chicago River, at Robey Street, 5.8 miles from the lake, up to which point the Chicago River had to be dredged, and extends to Lockport, a distance of 28.05 miles, where the water action is controlled. Here there is a basin of sufficient width to allow vessels to turn. The tail-race below Lockport, which carries the water to the Des Plaines River, is 6500 feet long. The flow of water through this race is controlled by sluice-gates and a dam. It was necessary, however, to carry the construction to Joliet, 7.1 miles farther, so that the total distance from the lake to Joliet is about 40 miles. The width of the canal is 160 feet at the bottom and 162 feet at the top, through rock, and 110 to 202 feet at the bottom and 200 to 300 at the top, through earthy soil, the actual width in most of the distance being but 100 feet, this being sufficient for the flow of water at the rate of 300,000 cubic feet per minute. The depth is 36 feet, with a minimum depth of water of 22 feet. The cost of the canal up to the time of ‘opening’ was about $33,000,000. The construction has been most of the time under the charge of Chief Engineer Isham Randolph. Current numbers of the Engineering News contain much information in regard to the canal. See Sewage Disposal.