Historical Information

Era of Non-treatment
1837-1855 Chicago is incorporated as a city. The City's primary source of drinking water is Lake Michigan. Chicago had no sewers.
1856

City began to build sewers that discharged into the Chicago River and Lake Michigan.

1860-1890

Experiencing a remarkable recovery from the devastating fire of 1871, Chicago rebuilt rapidly along the shores of the Chicago River. The river was especially important to the development of the city since all wastes from houses, farms, the stockyards and other industries could be dumped into the river and carried out into Lake Michigan. During a tremendous storm in 1885, the rainfall washed refuse from the river far out into the lake, past the water intake cribs. Typhoid, cholera and other waterborne diseases from the contaminated drinking water kills 12% of Chicago's population.
1889

The Illinois Legislature passed an Act establishing the Sanitary District of Chicago to keep sewage pollution out of Lake Michigan.

1892

Ground was broken for the 28 mile Main Channel of the Sanitary and Ship Canal.

Era of Treatment by Dilution
1900

Main Channel of the Sanitary and Ship Canal opened, reversing the flow of the Chicago River. Thus, water was diverted from Lake Michigan to dilute sewage. This is one of the seven engineering wonders of the world.

1907

North Shore Channel built to divert more lake water to aid dilution. Interceptor sewers completed. Lake Michigan protected from contamination.

Era of Treatment by Sewage Treatment Plants
1919

Ordinance passed by the District's Board of Trustees committing District to construction and operation of sewage treatment plants.

1922

The Cal-Sag Channel became operational.

1927-1939

In 1938, diversion restricted to an annual average of 1500 cubic feet per second. Construction of three main sewage treatment plants at Stickney (1939), Calumet (1935) and North Side (1927).

Era of Environmental Enhancement
1955

The District's name was changed to the Metropolitan Sanitary District of Greater Chicago.

1956

Referendum passed adding 412 square miles in Cook County to the District's service area.
1961 Lemont Treatment Plant placed in operation.
1967 Ordinance passed by District's Board of Trustees that would not permit any waste discharge into Lake Michigan. Solids-on-land concept called the "Prairie Plan" adopted. Research initiated on combined sewer overflow and flood control studies.
1971 Fulton County land reclamation project began. The "Prairie Plan" concept put into action the reclaiming of abandoned strip mines into agriculturally productive land.
1972 District adopted the Tunnel and Reservoir Plan (TARP) to solve combined sewer overflow problem.
1975-1980 Construction began on the 31 mile Mainstream system of TARP. In 1977, construction began on the 9.2 mile Cal-Sag leg of TARP. Egan (1975), Kirie (1980) and Hanover (1978) treatment plants placed into operation.
1985 District's 31 mile Mainstream Tunnel system began operation — capable of storing 1 billion gallons of combined sewage and stormwater.
1986 District's Mainstream System of TARP received national award as "Outstanding Civil Engineering Achievement of 1986" from the American Society of Professional Engineers. District's 9.2 mile Cal-Sag segment of TARP began operation.
1988 The Chicago Tribune reports "As a result of an aggressive cleanup program by the Metropolitan Sanitary District bold, imaginative efforts are being taken by private developers and the Chicago River is beginning to challenge the lakefront as Chicago's premier attraction."
1989 District celebrated 100 years of protecting our water environment. As part of the Centennial celebration, the District changed its name to the Metropolitan Water Reclamation District of Greater Chicago; built a Centennial Fountain on the north bank of the Chicago River at McClurg Court; and established a 26 mile Centennial Trail that weaves along three historic waterways — the Des Plaines River, the Sanitary and Ship Canal and the Illinois and Michigan Canal. District develops award winning plan for Sidestream Elevated Pool Aeration (SEPA) stations which are "Urban Waterfalls" to aerate the water in the Calumet River and Cal-Sag Channel to enhance the aquatic environment, improve and protect fish populations and eliminate odors.
1990 The Army Corps of Engineers and the District broke ground for the O'Hare Reservoir, the first project in Phase II of TARP. It will store 342 million gallons of floodwater.
1992-1994 District's five SEPA stations are completed along the Cal-Sag Channel. The District received the "Outstanding Civil Engineering Achievement of 1994" award from the American Society of Civil Engineers for these projects.

3/23/95