Up-Close Look at Water Management Complexity

Friends board members and staff stand beneath the scale-size outline of the Deep Tunnel.

Recently the board and staff of Friends of the Chicago River got an up-close look at the watershed-wide complexity of stormwater management, water treatment, and multi-benefit nature-based solutions at visits to the Metropolitan Water Reclamation District (MWRD) and the Forest Preserves of Cook County (FPCC).

The group met with MWRD engineers at the Mainstream Pumping Station located in the southwest suburbs and went more than 300 feet down to discuss the system and enormous pumps that move water to be treated through the underground Tunnel and Reservoir Plan (TARP), aka the Deep Tunnel. We also saw the massive McCook Reservoir which is connected to the Deep Tunnel. Stage 1 of the McCook Reservoir currently can hold more than 3.5 billion gallons of sewage, stormwater, and industrial wastewater; when construction of a second adjunct reservoir is complete in 2029, the McCook Reservoir will be able to hold more than 10 billion gallons. The Mainstream Pumping Station is the largest in the world and can pump more than one billion gallons of sewage per day from a depth of over 350 feet below the surface. TARP has contributed to the steadily improving health of the river system by drastically reducing combined sewer overflows which are harmful to people and aquatic life.

At a site visit to Country Lane Woods in the southwest Palos region of the county, we met with an ecologist of the FPCC who praised the value of our multiyear partnership including a large-scale restoration project which began in 2018 to enhance habitat in the Crooked Creek watershed. The watershed is within the Palos-Sag Valley region. This restoration project is dramatically improving habitat through invasive species control and removal, giving native species a chance to thrive. As of 2021, more than 425 acres have been restored including miles of riparian area along the headwaters of the Crooked Creek. The creek is a beautiful, winding tributary of the Chicago River system, provides critical habitat for the at-risk Hine’s emerald dragonfly, and is home to many fish species including largemouth bass, bluegill, and pumpkinseed. At 15,000 acres, the Palos Preserves in southwest Cook County are the largest concentration of preserved land in the Forest Preserves. Learn more about Crooked Creek and the Palos Preserves on our Inside, Out & About podcast.