Did you ever wonder where sewage water goes, or what happens to water that has been flushed down the toilet?  I had the privilege of visiting the Terrence J. O’Brien Water Reclamation Plant to learn more about this.  This facility serves approximately 1.3 million residents living in both the northern part of Chicago and in seventeen of its northern suburbs in Cook County.  People can request tours to see this water reclamation plant, as well as others in the Chicago area.  However, I visited the plant during Open House Chicago, which is a weekend event that happens every October in Chicago in which different buildings, museums, etc. open up their spaces for free to the public.

The Metropolitan Water Reclamation District of Greater Chicago (MWRD) began in 1889.  Among its early projects was reversing the Chicago River so that it flowed away from Lake Michigan (Chicago’s source of drinking water) rather than towards it.  As Chicago grew in population, so did its need for reclamation plants.  The Stickney Water Reclamation Plant in Cicero, Illinois was built in 1930, and is among the largest in the world.  The Terrence J. O’Brien Water Reclamation Plant was built in 1928, and originally called the North Side Sewage Treatment Works.  It was renamed in memory of a Board Commissioner in 2012.  Although people can tour Chicago’s water reclamation plants, they cannot tour the plant that deals with Chicago’s drinking water, due to security concerns.  This is the Jardine Water Purification Plant, located north of Navy Pier.

My tour of the Terrence J. O’Brien Water Reclamation Plant began with watching a video, which provided an overview of the water reclamation process.  This video is available on YouTube.  Next, we walked over to the areas mentioned in the video.

Although we walked to this section last, the first step in the water reclamation process is to remove the largest sewage materials, which, according to my guide, can include strange things like dead rats.  The waste is first removed in the Pump and Blower Building.  From there, the largest material waste goes down a tube, southeast to the Stickney Water Reclamation Plant in Cicero, Illinois.  At that facility, waste is transformed into compost.

What does not go to Stickney ends up going through the rest of the Terrence J. O’Brien Water Reclamation Plant.  First, the water goes into circular vats, where the remaining solids sink.  The secondary treatment includes microorganisms that “eat” away the bacteria.  Lastly, the water gets pumped into an Ultraviolet Wastewater Disinfectant Facility, where UV light helps kill additional bacteria.  Completed in 2016, this is currently the largest UV disinfectant facility in the world.  Once the water treatment process has finished, the water flows into the North Branch of the Chicago River, located across the street from the Terrence J. O’Brien Water Reclamation Plant.  Apparently, the water exiting the Reclamation Plant is cleaner than the River, which is believable, because the North Branch of the Chicago River never looks clean.

People riding the Yellow Line (Skokie Swift) of the CTA (Chicago Transit Authority), which is the elevated train (the “L”) that connects Chicago to its northern suburb of Skokie, have a great view of the Terrence J. O’Brien Water Reclamation Plant.  Since this is an elevated train, it passes right over the facility.

---

Sources and Further Reading

“Facility Tours.” Metropolitan Water Reclamation District of Greater Chicago. https://mwrd.org/facility-tours (accessed May 8, 2020).

Fore, Allison. “North Side Water Reclamation Plant is Renamed to Terrence J. O’Brien Water Reclamation Plant.” Patch. November 16, 2012. https://patch.com/illinois/chicagoheights/bp–north-side-water-reclamation-plant-is-renamed-to-76d7ad1a48 (accessed May 8, 2020).

Garcia, Evan. “World’s Largest Ultraviolet Disinfection Facility Tackles Chicago River.” WTTW. March 23, 2016. https://news.wttw.com/2016/03/23/worlds-largest-ultraviolet-disinfection-facility-tackles-chicago-river (accessed May 8, 2020).

MWRD. “Terrence O’Brien Water Reclamation Plant Video Tour.” March 11, 2019. Video, 7:41. https://www.youtube.com/watch?v=oJ4IbCBf7g0 (accessed May 8, 2020).

“One Water Spotlight: Stickney Water Reclamation Plant.” US Water Alliance. http://uswateralliance.org/resources/one-water-spotlight-stickney-water-reclamation-plant (accessed May 8, 2020).

“Terrence J. O’Brien Water Reclamation Plant.” Open House Chicago. https://openhousechicago.org/sites/site/terrence-j-obrien-water-reclamation-plant/ (accessed May 8, 2020).

“Our History.” Metropolitan Water Reclamation District of Greater Chicago. https://mwrd.org/our-history (accessed May 8, 2020).