Illinois data centers drain millions of gallons of water daily—raising alarm

Illinois faces growing concerns over water usage as data centers consume millions of gallons daily. These facilities, mostly in Chicago, rely on municipal drinking water for cooling, raising fears about long-term supply. Experts now warn that better planning is needed to prevent shortages. Data centers across Illinois are putting significant pressure on the state’s water resources. A single facility can use up to 5 million gallons in one day—roughly the same as a medium-sized town. Most of this water, drawn from Lake Michigan, is lost after cooling and not returned to the system.

Nationwide, data centers consumed 17.4 billion gallons in 2023, with projections suggesting this could rise to 72.6 billion gallons by 2028. In Illinois, the strain is particularly acute, as Lake Michigan, though vast, has a limited supply. The Illinois Department of Natural Resources has so far declined to comment on the issue. Scientists and advocates are pushing for alternative solutions. One proposal involves using treated wastewater from plants to supply data centers instead of drinking water. Without action, they argue, the state risks worsening water scarcity in the coming years.

The rapid expansion of data centers has made water management a pressing issue for Illinois. Without changes, the state’s reliance on Lake Michigan and municipal supplies could lead to shortages. Alternative sources, like treated wastewater, may offer a way to ease the strain on existing resources.