Illinois struggles to balance data center growth with dwindling water supplies

Illinois faces growing pressure to manage water consumption by data centers as demand surges. Experts warn that without immediate action, the state’s water supply could come under severe strain. The issue has become urgent as facilities in Chicago and beyond rely heavily on municipal drinking water for cooling operations. Data centers across Illinois currently consume millions of gallons of water each day. A single facility can use up to 5 million gallons in 24 hours—roughly the same as a medium-sized town. Unlike household water, this supply is not returned to the system after use, raising concerns about long-term sustainability.

Lake Michigan, the main water source for the Chicago area, provides most of the region’s drinking water. But its capacity is not unlimited, and rising demand from data centers threatens to stretch supplies thin. Nationally, water usage by these facilities is set to quadruple by 2028, jumping from 17.4 billion gallons in 2023 to 72.6 billion gallons. Experts suggest Illinois could ease the pressure by adopting strategies from states like California. One key solution involves using treated wastewater instead of drinking water for cooling. This approach would reduce reliance on municipal supplies while ensuring data centers continue to operate efficiently.

The call for action comes as Illinois weighs the balance between technological growth and water security. Shifting to wastewater reuse could help protect drinking water reserves for residents. Without changes, the state risks facing shortages as data center demand continues to climb.