On Monday, July 27, 2026, Chicagoans witnessed an unusual spectacle as manholes across the city erupted like geysers during intense rainstorms. Videos shared on social media captured jets of water bursting from manhole covers in the Loop, West Loop, and Pilsen neighborhoods, as the city experienced heavy downpours. This phenomenon, known as urban geysers is becoming increasingly common in cities across the country as climate change intensifies rainfall and stresses aging infrastructure.
The city’s sewer system, much of which was constructed over a century ago, is struggling to cope with the increased volume of water. The Metropolitan Water Reclamation District explains that the original design was intended to handle sanitary flow and limited stormwater, directing it to the river before wastewater treatment became standard. Today, Chicago’s combined sewer system carries both household wastewater and rainwater to treatment plants, but during heavy rain, excess flow is diverted to the Tunnel and Reservoir Plan, adopted in 1972. Even this system, which includes the largest sewer reservoir in the world has been pushed to near capacity this summer due to extreme storms.
Climate change and infrastructure challenges
Susannah Drake a landscape architect and instructor at the University of Colorado Denver, explains that climate change is leading to more powerful downpours over shorter periods. This intense influx of water creates trapped air pockets and pressure differentials, forcing air and water upward through manholes and lifting their covers. Drake likens this to putting your thumb on a hose to make the water spray faster and farther.
The problem, according to Drake, is that the city’s pipes are often too small to handle the increased rainfall. This causes water to build up in the pipes and shoot out backward through the manholes rather than draining into treatment plants or combined sewer overflow systems. It’s a capacity issue she states, highlighting the urgent need for solutions to redirect excess rainwater.
Green infrastructure as a solution
One potential solution is the implementation of green infrastructure to absorb surface water runoff. Chicago’s green alleys serve as an example of this approach. These alleys act like sponges and runways for rainwater, allowing some water to seep into the ground while the rest gathers into grooved channels and streams into manholes connected to local sewers. The underground trench system can absorb thousands of gallons of rainwater every hour.
However, Drake points out that part of the challenge is that there aren’t a lot of permeable spaces in cities. With roads, sidewalks, buildings, and roofs covering much of the urban landscape, water is forced into drainage systems. Without permeable spaces, there’s no flexibility, and water has nowhere to go except into the drainage systems. This lack of permeable spaces exacerbates the issue of urban geysers during heavy rain.
Chicagoans can report urban geysers via the city’s 311 system to request dispatch from the Department of Water Management. As climate change continues to intensify rainfall, cities like Chicago will need to devise innovative strategies to manage excess rainwater and protect their aging infrastructure.
