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Metropolitan Water Reclamation District of Greater Chicago

MWRD engineering achievements reversed flow of Calumet River system and introduced wastewater treatment to protect public health and water quality

Within the span of a month in 1922, the Metropolitan Water Reclamation District of Greater Chicago (MWRD) -- then known as the Sanitary District of Chicago -- completed two monumental engineering feats to protect the health of the region and local water quality. A century later, the Calumet Water Reclamation Plant (WRP), Cal-Sag Channel, and reversal of the Calumet River system remain as pillars supporting public health and regional water environment.

The MWRD will mark this occasion at its 10th Annual Sustainability Summit to be held at the Ford Calumet Environmental Center, 11555 S. Stony Island Ave. in Chicago, on Friday, Oct. 21 at 10 a.m. Registration starts at 9 a.m. The 100th Anniversary of the Calumet WRP will be highlighted among several presentations with a photo exhibit and discussion, and members of the MWRD’s first Community Partnership Council will be announced to promote community engagement within the communities the WRP serves. More information on the Sustainability Summit.

After 11 years of construction, the gates at the Blue Island Lock on the Little Calumet River were opened on Aug. 18, 1922, diverting water to flow into the new Cal-Sag Channel for the first time. By Aug. 26, the Cal-Sag was fully operational. This action began the process to allow the MWRD to reverse the flow of the Little Calumet River west away from Lake Michigan, protecting the supply of drinking water and providing integral drainage to shelter and enhance the Far South Side.

A few weeks later on Sept. 11, 1922, the MWRD completed construction of the Calumet WRP, 400
E. 130th St., Chicago. The new facility implemented emerging treatment technology that could transform wastewater from across the area into clean water. Today, the Calumet WRP is the longest-tenured MWRD water reclamation plant, serving more than 970,000 people each day from Chicago and 48 surrounding suburbs and providing around-the-clock services. The Calumet WRP can treat up to 450 million gallons of water each day, generating renewable energy and recovering vital resources to protect the planet and taxpayers. In addition to building the plant and digging the 16-mile Cal-Sag Channel, the MWRD built 6 other WRPs and nearly 184 miles of intercepting sewers to convey water from municipal sewers to its treatment plants.

“This September we recognized 100 years of service, innovation and ingenuity at our Calumet Water Reclamation Plant and the work of our predecessors to construct the Cal-Sag Channel,” said MWRD President Kari K. Steele. “These measures that we often take for granted have had a profound impact on our way of life, and today bolster our homes and businesses and keep our water environment safe.”

The MWRD reversed the Chicago River through the construction of the Chicago Sanitary and Ship Canal (1900) and reversed the North Branch of the Chicago River through the construction of the North Shore Channel (1910). But as the rest of the Chicago River reversed, the Calumet River was still flowing out to Lake Michigan, causing concern for waterborne illness and polluted water flowing out to the source of the region’s drinking water in Lake Michigan. Like the Sanitary and Ship Canal, the MWRD discovered the Calumet River system could also flow west by building a new canal that allowed gravity to funnel water through the subcontinental divide away from the Great Lakes toward the Mississippi River Basin.

The 16-mile Cal-Sag Channel continues serving as the link to keep water flowing west, connecting the Calumet River system to the Chicago Sanitary and Ship Canal and downstream to the Des Plaines River, Illinois River and Mississippi River to the Gulf of Mexico. Today it is a thriving waterway attracting a surging population of fish, birds and recreation, and its construction generated a boom of economic opportunity, helping establish towns and attract residents, commerce and community life.

“We celebrate the work of those before us who introduced transformative environmental protections which lead to recreational opportunities, industrial growth, and community and economic development throughout the region,” said MWRD Commissioner Kimberly Du Buclet. “Our region has come a long way and we are still pursuing an even better quality of life for the residents that live and work here.”

22_08xx_Calumet turns 100.pdf

Press Release

Established in 1889, the Metropolitan Water Reclamation District of Greater Chicago (MWRD) is an award-winning, special purpose government agency responsible for wastewater treatment and stormwater management in Cook County, Illinois.


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