T5 Data Centres has received its first building permit for an 800,000‑sq‑ft data‑centre campus on Peterson Road in Grayslake, Illinois, after the village approved the initial phase of the $18 billion project.
The campus is slated to cover 6.7 million sq ft over 7–10 years, a scale up from an earlier plan of 10.1 million sq ft on 473 acres. The village’s latest documents show the first phase will occupy roughly 800,000 sq ft, the footprint of a large office building.
Opposition emerged when residents learned of the project’s true size only after approvals were granted. Rob Baum, who has owned land near the site for three generations, said he thought the area was farmland until the permit appeared. Hannah Harris added that the approval language was ambiguous, causing her to attend meetings too late.
Legal action has followed: a lawsuit filed by the Lake County Data Centre Opposition Coalition seeks to invalidate the permits, while the village argues the hearings met all statutory requirements. The case now awaits a court hearing in the next month.
T5 and the village emphasize the economic upside. The project is projected to generate about $1.4 billion in property‑tax revenue over 20 years, with no tax incentives or debt financing. T5 has pledged closed‑loop cooling, estimating 50,000 gallons of water per day for the full campus, and will fund the electrical substation needed.
Construction is slated to begin in early 2027, pending the lawsuit’s outcome. If the court upholds the permits, the first phase will break ground soon after, sparking a flurry of activity across the community and the data‑centre industry.