Construction of the Calumet Water Reclamation Plant (WRP) on September 29, 1921. The Calumet WRP is the oldest of the MWRD’s seven WRPs and has been in operation since 1922, serving residents and businesses in the southern portion of Cook County. At the time of its opening, the 16-mile Calumet-Saganashkee (Cal-Sag) Channel had just become operational. By 1928, the plant served a population of 155,000. At present the plant’s service population is over one million people in an area of about 300 square miles.The communities downstream of Chicago were not happy with Chicago reversing the flow of the river and dumping their sewage and stock yard wastes into their source of drinking water, including St. Louis. MWRD's predecessor finally decided to stop paying for lawyers and to start paying for concrete. Years ago I read that the sanitation district helped pioneer large scale water reclamation. In fact, the Stickney Plant is still the worlds largest. (History1, History2) (It is interesting how the terminology has been "cleaned up" over the decades. When I was a kid, it was "sewage treatment," then it was "waste water treatment," now it is "water reclamation.")
In just the last few years, once again the MWRD decided to pay for equipment instead of lawyers. This time they were fighting the EPA about the bacteria they were dumping into the river.
U.S. Sen. Dick Durbin noted that Chicago was the last major city in the U.S. to disinfect its treated wastewater.Note the implication that Chicago has been uncivilized until the 21st century. So Chicago was one of the first metropolitan areas to build sewage treatment plants, but one of the last to kill the bacteria in its water output.
"This disinfection facility now brings Chicago into the civilized world when it comes to the treatment of sewage and the discharge," Durbin said. (Tribune)
Update: this plant uses the old technique of adding chlorine then removing the chlorine. The O'Brian Plant uses a new technique of ultraviolet radiation.