Increasingly overwhelmed by the city’s population, aging infrastructure systems throughout Chicago could begin to threaten the environment in the coming years if nothing is done to fix them.

According to The DePaulia, evidence of sewer system overload is already apparent throughout much of the city. When last summer brought heavy rains and flash flooding, Chicago’s century-old sewer lines — buried 12 to 24 inches below the city streets — weren’t equipped to cope with the extra storm water.

When Chicago’s sewer systems and water treatment plants can’t handle these intense storms, this water overflow goes into the Chicago River. But to keep the river from rising onto city streets, Metropolitan Water Reclamation District officials are often forced to release extra sewage and rain water into Lake Michigan. Last summer, the city released 525 million gallons of sewage and storm water into Lake Michigan.

And with climate experts and city officials predicting that these storms will only get more intense and unpredictable as time goes on, current sewer line repair projects might be another case of too little, too late.

“There is a new kind of storm hitting Chicago in recent years — heavy rains that can be very local, very intense and hard to predict,” a city website that pushes for preventative flood programs said. “They dump two inches or more per hour on a given neighborhood. This volume quickly overwhelms local sewers, which were not designed for such intense rainfall. Sewer mains fill up, and additional water pushes into basements through our private drains.”

Chicago’s sewer system overflow isn’t all that threatens the local ecosystem. According to a June 4 report from The Chicagoist, methane leaks from natural gas pipelines around the city pose a risk to the climate. In the city’s older neighborhoods, especially, these leaks are most prominent, indicating a clear need to upgrade and fix these leaks.

In fact, 40% of Chicago’s gas pipelines are more than half a century old, the Environmental Defense Fund found. And while these methane leaks don’t necessarily create an immediate threat to the environment, it’s clear Chicago’s leadership will need to prioritize pipeline upgrades in the near future.