A massive data-center campus planned in Grayslake, Illinois, has moved a step closer to construction after the village issued its first building permit, paving the way for an 800,000-square-foot facility
The larger development is expected to involve as much as $18 billion in private investment, but the project has also triggered opposition from residents who say they were not given a meaningful opportunity to weigh in before approvals were granted.
The Project
The T5 Data Centres project, known as the Cornerstone development, is planned on land along Peterson Road in Grayslake. The latest plans call for about 6.7 million square feet of data-centre space to be built over 7 to 10 years. Earlier approvals allowed for a larger development of up to about 473 acres and as much as 10.1 million square feet
The village said the initial permit marks the operational start of the multibillion-dollar campus, with site work moving forward. While the village and developer have promoted the project as a major economic investment, some nearby residents say they were unaware of the scale of the development until after key approvals had already been granted.

Residents React
CBS Chicago reported that residents living close to the future data centre said they did not realize what was planned until the project had already been approved.
Rob Baum, whose family has owned property near the site for three generations, said he believed the land was simply farmland and was surprised by the scale of the planned construction. “This was all farm field,” he said. “My uncle owns like five acres back there. It seemed like they kinda snuck it under the table a little bit.”
Hannah Harris, another resident, told CBS that residents did not understand that the project was being approved because of what she described as “ambiguous language.” She said she began attending village meetings after learning more about the development, but by then the project had already received approval.
The Concerns
The concerns extend beyond the size of the buildings. Residents have raised questions about potential environmental effects, water consumption, electricity demand, noise, and wetlands around the site.
The opposition has also moved into the legal arena. A lawsuit filed by opponents seeks to challenge the village’s approvals, while residents have organized through the Lake County Data Centre Opposition Coalition. Opponents argued that the public hearings surrounding the approvals were inadequate and that the village did not commission third-party studies to support some of its conclusions.
The Developer’s Response
T5 Data Centres has defended the development and said it intends to continue engaging with residents. Pete Marin, CEO and chairman of T5, said the company was committed to incorporating community input. He pointed to the company’s decision to voluntarily withdraw an application related to the remediation of local wetlands after hearing concerns from residents.
T5 has also said it is working with the village on standards involving noise, water, and electricity use. The company has said the project is expected to generate about $1.4 billion in property tax and permit-fee revenue over 20 years.
The Village’s Position
The Village of Grayslake has emphasized the financial impact. According to village officials, the project is moving forward without local tax incentives, exemptions, or tax-increment financing subsidies. The village estimates the campus could generate approximately $1.4 billion in property tax revenue for local taxing bodies over its first 20 years.
The village currently operates with a balanced budget and no municipal debt, officials said, meaning the additional revenue could potentially support infrastructure, parks, trails, schools, and other community projects.
Water and Power
Data centres have attracted increasing attention in the US because of their electricity and water requirements, particularly as artificial intelligence drives demand for computing capacity. Grayslake officials say the planned campus will use closed-loop cooling systems and estimate that an average data-centre building would consume around 2,500 to 3,500 gallons of water a day. For the full 6.75-million-square-foot campus, the village estimates total water use at approximately 50,000 gallons per day.
The developer is also expected to fund the electrical infrastructure the campus requires, including an electrical substation on the property.
The Bottom Line
Illinois has issued its first permit for an $18 billion data-centre campus in Grayslake. The project will cover up to 472 acres and include 6.7 million square feet of data-centre space built over 7 to 10 years. Residents say they were not given a meaningful opportunity to weigh in before approvals were granted, and a lawsuit has been filed to challenge the village’s decisions. The developer says it is committed to community engagement, and the village says the project will generate $1.4 billion in property tax revenue over 20 years.
My opinion
Data centers are coming because the AI boom demands them the economic benefits are real. Grayslake stands to gain $1.4 billion in property tax revenue over 20 years but the way this project was approved is a problem.
Residents say they did not know what was being built until it was already approved. They describe ambiguous language, missed meetings, and a process that moved faster than they could respond. That is not how local government is supposed to work. Public hearings exist for a reason. If residents feel like something was “snuck under the table,” the process failed them — even if the outcome is legal.
T5 deserves credit for withdrawing its wetlands application after hearing concerns. That is a sign of good faith. But good faith after the fact does not replace meaningful participation before the fact. The lawsuit filed by opponents may or may not succeed. But the frustration behind it is legitimate.
The real question is not whether Grayslake needs the money. It is whether the community should have a say in how its landscape is transformed. Right now, the answer appears to be no. And that is a loss for everyone involved.





