Illinois data centers are using millions of gallons of residential water; experts say there are better alternatives
Data centers popping up all over Illinois are sucking up millions of gallons of water a day, at a pace that the state can't keep up with.
With the Chicago area situated next to the massive Lake Michigan, which contains over 1 quadrillion gallons of water, we can forget there isn't an endless supply of water. And experts dealing with the impact of data centers used to train and power AI say we have to shift that thinking, because Chicago can't keep up with the water needs we're now seeing.
"When it comes down to it, the water available for human uses from the lake are not limitless," said Rachel Havrelock of The Freshwater Lab at University of Illinois Chicago.
One data center is able to use 5 million gallons of water in a single day, the same amount of water as a medium-sized town. That water doesn't go back into the water system.
"Often times these cooling systems are what we call evaporative cooling that means the water is lost to the system," Havrelock said.
Most data centers in the Chicago area rely on municipal drinking water – the same water you're getting at home – to cool their computers, servers, equipment and other systems. But it doesn't have to be that way.
"Our wastewater treatment plans can supply data centers and this is what I call, in Illinois, the low-hanging fruit," said Havrelock.
Experts say states like California figured that out a long time ago, and Illinois can too before it becomes a real problem.
"If we don't enlarge our water portfolio right now we're going to be looking at some devastating choices in the near future," Havrelock warned.
"If we are able to plan, we are able to ensure our water supply is much more steady," said Andrea Densham, director of regional government affairs for the Alliance for the Great Lakes. "We have to be really thoughtful in our region about who takes our water and how much is taken. That's why we think when it comes to data centers it's really about planning and management."
In 2023, U.S. data centers accounted for 17.4 billion gallons of water use, according to a study from The Freshwater Lab. That number is expected to grow to 72.6 billion gallons by 2028.
That's why scientists and advocates say Illinois needs to navigate the water issues now.
"We need to, right now in 2026. bring the water we use as waste into productive use," Havrelock said.
"It's really important when we're thinking about these data centers that we don't have just anybody putting a straw up to our groundwater systems and pulling up whatever they want and not thinking about how it impacts the availability for drinking water or for agriculture," said Densham.
CBS News Chicago Investigators reached out to the Illinois Department of Natural Resourced on this topic, but they did not want to be interviewed and did not send any information via email.
Further Resources
Water Procurement for Data Centers – UIC Water Recycling Team
Water Recycling information – The Freshwater Lab
