For immediate release
October 9, 2019

McCook Live Stream
McCook Reservoir Stage I fills to hold up 3.5 billion gallons along with 1.6 billion gallons in the adjoining tunnels that feed into it. The water is held there until the MWRD can treat it. That untreated water formerly overwhelmed local sewers and overflowed into local waterways.


For those interested in watching one of the nation’s largest public works projects for water quality in action, simply visit the Metropolitan Water Reclamation District of Greater Chicago (MWRD’s) website at The MWRD is now live streaming the McCook Reservoir Stage I during daylight hours as it takes on billions of gallons of stormwater and untreated wastewater. 

Part of the MWRD’s Tunnel and Reservoir Plan (TARP), the McCook Reservoir has proven to be a critical piece of infrastructure since it went into service in late 2017 to mitigate flooding in the Chicago area’s combined sewer systems, while also protecting the area water environment from pollution by containing water for later treatment. This untreated water, which previously overwhelmed sewers and flowed into local waterways, can now be pumped back to the Stickney Water Reclamation Plant for treatment.

“We are thrilled to offer this live stream of McCook Reservoir to allow viewers at home to watch their hard-earned tax dollars put to work to protect our water environment through this massive and critical infrastructure,” said MWRD Commissioner Mariyana Spyropoulos. “Viewers will be able to witness water flowing into the reservoir and catch a glimpse at how this unique system works during these demanding and changing weather patterns.”

In 2018, in its first year of operation, the reservoir captured 27.2 billion gallons of water. Combined with the adjoining Mainstream and Des Plaines tunnels that feed into the reservoir, the whole McCook system captured 46.1 billion gallons in 2018. From January through July 2019, the entire TARP system captured 58 billion gallons of water. If not for TARP, that is 58 billion gallons that could have polluted local waterways.

“The live footage of McCook Reservoir offers a new vantage point into the work of the MWRD striving to meet our mission in both improving water quality and protecting homes and businesses from flooding,” said MWRD Commissioner Kim Du Buclet. “It also serves as a reminder on those rainy days to help us increase capacity in this system by reducing the amount of water that flows down your drains. By conserving more water during storms, we can prevent taxing these pivotal collection systems.”

The MWRD will be able to capture more water when McCook Reservoir Stage II comes online with a storage capacity of 6.5 billion gallons. Between the two stages of McCook Reservoir, the MWRD will be able to capture 10 billion gallons of storage, large enough to fill 200 million rain barrels. The McCook Reservoir in its entirety will be 6,400 feet long by 1,000 feet wide and 300 feet deep.

In February 2019, the MWRD and project partners at the U.S. Army Corps of Engineers Chicago District entered into an agreement on a federal funding plan to complete Stage II by 2029. Once fully complete, the McCook Reservoir will provide more than $143 million per year in flood damage reduction benefits to 3.1 million people in 37 communities, including Chicago.