Billions of Gallons of Untreated Sewage Pour into Chicago Waterways
Chicago’s aging sewer infrastructure and intensifying storms have forced pumping stations to dump more than 10 billion gallons of raw sewage into local rivers and creeks this year, according to reporting by the Chicago Sun-Times and WBEZ. Intense weather patterns dropping rain faster than the system can manage have overwhelmed underground tunnels and reservoirs, sending feces, tampons, and condoms floating past urban paddling routes and wildlife habitats.
Ten Billion Gallons at the Racine Avenue Station
The Racine Avenue pumping station on the South Side has dumped more than 10 billion gallons of untreated sewage into the South Branch of the Chicago River this year, marking its highest volume since 2019. The nearly 90-year-old station moves combined wastewater and stormwater toward treatment facilities, but heavy rains force the Metropolitan Water Reclamation District of Greater Chicago to divert raw sewage directly into the water to prevent residential basement backups.
Along Bubbly Creek, a stretch dividing Bridgeport and McKinley Park near the Bridgeport Art Center, the discharges leave visible layers of waste caught in shoreline trees. Joe Gamble, who works at the Chicago Maritime Museum nearby, notes that strong sewage odors frequently linger on his clothes even after he leaves the area. The water reclamation district operates under a 2011 binding agreement with the U.S. Environmental Protection Agency regarding federal clean water violations tied to these overflows.
Two Billion Gallons on the North Side
The water reclamation district’s North Branch pumping station near Albany Park and Lincoln Square has spewed nearly two billion gallons of untreated sewage into the North Branch of the Chicago River this year. The combined sewer system handles both domestic waste and stormwater runoff, leaving it vulnerable when downpours exceed system capacity. While the network is engineered to handle about two inches of rain in a 24-hour period, recent storms have dropped more than 8.5 inches within the same timeframe.
Tara Hoffmann, executive director of Recovery on Water, a rowing team for breast-cancer survivors, observes members paddling through contaminated water where fish surface gasping for air.
Deep Tunnel and Reservoir Limits
The multibillion-dollar Deep Tunnel project—formally known as the Tunnel and Reservoir Plan—spans more than 100 miles of underground tunnels designed to capture floodwaters and protect Lake Michigan and regional rivers from pollution. However, climate change has accelerated extreme weather events that outpace the capacity of the underground network and its holding quarries.
This summer, the Thornton reservoir in South Holland filled with stormwater for the first time since opening in 2015, holding nearly eight billion gallons of water. To the west, the McCook reservoir in Bedford Park filled to capacity 10 times this year, compared to just five times between its 2017 opening and last year. The McCook facility is undergoing an expansion to hold 10 billion gallons by 2032, three years later than the district previously reported to the EPA.
Ecosystem Impacts on Urban Rivers
Researchers tracking the ecological toll note that sewage surges trigger sudden oxygen depletion and nutrient spikes that devastate aquatic life. Phil Nicodemus, research director for Urban Rivers, explains that these organic loads cause massive oxygen drops that can wipe out fish populations for weeks. Austin Happel, a research biologist from the Shedd Aquarium who studied Bubbly Creek following a 2023 spill, found that nitrogen levels rose significantly while oxygen levels crashed, shifting the local food chain.
Environmental advocates argue that traditional engineering alone cannot solve the overflow crisis. Margaret Frisbie, executive director of Friends of the River, agrees that the efforts are not keeping up in the race against time and nature.