An $18 Billion, 1.55-Gigawatt Data Center, a County Moratorium and a Fight Over Local Control

On September 8, 2026, the Lake County Board in Illinois approved an eight-month pause on new data centers. The pause covers unincorporated land, which is land outside any city or village. It runs to May 11, 2027, unless the board adopts data center rules sooner, the Lake and McHenry County Scanner reported. The county has received no data center proposals for that land.

The pause does not reach the Village of Grayslake. Grayslake has already approved a campus called T5 @ Chicago IV, from T5 Data Centers. The village's own fact sheet, updated August 25, puts it at 473 acres and an estimated $18 billion in private investment. It says the latest plans call for 6.75 million square feet in 11 buildings, built over seven to 10 years. On September 1, Grayslake announced the first building permit, for an 800,000-square-foot building.

Residents sued on July 31 to undo the village's approvals. The first court date is October 30. The county now has two different answers to the same question: a pause on unincorporated land, and a permit inside one of its villages.

At a Glance

• Item: Lake County's eight-month pause on data centers outside cities and villages, and the separate Grayslake approval of T5 @ Chicago IV.
• Vote: The county committee that reviewed the pause voted 6-0, with one member absent, according to its minutes. The full board voted unanimously on September 8, the Daily Herald reported.
• Project: T5 @ Chicago IV in the Cornerstone business park, near Peterson and Alleghany roads, west of Route 83. 473 acres; latest plans 6.75 million square feet in 11 buildings, per the village fact sheet of August 25.
• Power: The village fact sheet gives no power figure. The lawsuit, as reported by the Scanner, cites about 1.55 gigawatts from ComEd. ComEd is the Chicago-area electric utility, and one gigawatt is 1,000 megawatts.
• Effect: The county pause stops new requests on land outside cities and villages. It does not apply to Grayslake or any other village or city.
• Fiscal impact: Village officials project $1.4 billion in property tax revenue over 20 years, and say no local tax breaks were used.
• Court: A lawsuit by nine residents and a company asks a judge to void the approvals. First hearing: 9 a.m., October 30, Courtroom 301, Lake County Circuit Court.

What Lake County Approved

The county's action came in steps. In June, the County Board told its Zoning Board of Appeals to hold a public hearing on a pause. It also let county staff stop reviewing data center applications for up to four months, the Scanner reported on June 20. No request was pending.

The Zoning Board of Appeals held its hearing on August 18 in Libertyville. The Scanner reported that residents packed the room and that the board voted 6-0 to recommend the change.

The next stop was the county's Planning, Building, Zoning and Environment Committee. Its minutes show a motion by Member Wasik, seconded by Member Campos. The committee voted 6-0 to send the ordinance to the full board. Chair Altenberg, Vice Chair Pedersen and Members Campos, Frank, Knizhnik and Wasik voted yes. Member Schlick was absent. The county's September 8 bulletin said the committee approved it unanimously on September 2.

The full board acted on September 8. According to the Scanner, the ordinance defines a data center. It is a facility that houses computer, network and server equipment, plus its cooling, power and backup systems. It covers one building or a campus. County staff will now write the longer-term rules: definitions, zoning categories, performance standards and review steps. The Daily Herald reported that staff may also look at community benefit agreements. Staff will watch a proposed state bill called the POWER Act. It would require data centers to report water and electricity use.

The Daily Herald reported that, with another administrative action, the pause could last up to a year. Board member Paul Frank raised the issue in December. On September 2, the Daily Herald reported, he said: "This moratorium will give us time to do better." In June, board member Esiah Campos cited water use and electricity demand as concerns.

What Grayslake Approved

The T5 campus is inside Grayslake, so the village, not the county, made the decision. The county's data center page says the county "does not have the authority to approve, deny, or impose zoning conditions on the project."

The Daily Herald reported that an advisory committee and the village board approved the project in hearings and meetings between September 2024 and May 2025. The Scanner gives the same dates. The site is part of Cornerstone, a $750 million, 641-acre mixed-use development, the Scanner reported. Alter Asset Management Company is its master developer.

Mayor Elizabeth Davies gave the village's account in a video posted September 28. She recorded it because the August 20 session could not be held. She said the village held 33 meetings on Cornerstone. The original zoning took 18 meetings and four public hearings. The data center approval took 11 meetings over eight months, with no limit on public comment. She said no elected official or anyone at village hall signed a non-disclosure agreement.

On September 1, the village announced it had issued the first building permit. The Daily Herald reported on October 3 that the first building is in foundation work and that work on an electric facility is expected to start soon. The village said: "By no means is this permit a blank check." It said T5 must meet state and local rules.

The village says the project got no local tax breaks, no property tax exemptions and no tax increment financing. That is a deal that sets aside part of a project's new property taxes to pay for local costs.

The Lawsuit

On July 31, the Preservation of Community Well-being Collective LLC and nine Lake County residents sued in Lake County Circuit Court. The defendants are the Village of Grayslake, T5 Data Centers, LLC, and Alter Asset Management Company.

The suit asks the court to declare the 2024 and 2025 approvals invalid. It asks the court to void the development agreement between the village and T5. It also asks for a permanent bar on any more permits based on those approvals. The Scanner reported these claims in the complaint:

• Planning: The approvals depart from the village's own plan for the area.
• Public notice: Notices used the code name "T5@Chicago IV." They did not say it was a very large data center until the last agenda in the approval process.
• Open meetings: The mayor and trustees did village business on personal email and devices, in violation of the Illinois Open Meetings Act.
• Zoning: The village's zoning code has no data center category.

The complaint also says a hearing on September 9, 2024, where the last residential uses in Cornerstone were removed, opened at 6:02 p.m. and closed at 6:03 p.m. with no public comment. These are the plaintiffs' allegations. A judge has not ruled on them.

The Daily Herald reported on October 3 that the village has filed a motion to dismiss. A village memo cited by CBS Chicago says the village will not answer questions about the project. It cites the lawsuit and advice of its lawyers.

T5's chief executive, Pete Marin, told the Scanner: "we're confident we've followed the letter and intent of every law and regulation every step of the way."

Wetlands, Water and Power

The Lake County Stormwater Management Commission reviews erosion and runoff plans. Its director reported in minutes posted in late June. He said the T5 project proposed to permanently fill 15.75 acres of wetlands. The village fact sheet calls it 16 acres.

The Scanner reported on August 8 that T5 suspended its wetlands permit request just before the lawsuit was filed. In her September 28 video, Davies said the developer removed the request and will not build on the 16 acres. She said:

The plan that the village approved that the developer submitted did not build on those 16 acres.

On water, the village fact sheet estimates about 50,000 gallons a day for the whole campus, or 2,500 to 3,500 gallons a day for an average building. The village supplies about 1,375,000 gallons a day. The Central Lake County Joint Action Water Agency told Chronicle Media that a 100-megawatt building needs about 1.6 million gallons for its first fill of cooling water. Associate Village Manager Zach Smith said the demand is not significant compared with the village system and that the design uses closed-loop cooling.

On power, Marin told the Scanner the project "has virtually no effect on electric rates for residents or local businesses."

How the Money Is Described

The village estimates $1.4 billion in new property tax revenue for local taxing bodies over 20 years. The village's fact sheet says that after the first 20 years, the buildings would pay nearly $100 million a year in property taxes across all the taxing bodies. It calls these preliminary estimates. Village officials describe the expected private investment as $18 billion.

In her video, Davies listed ways the village could use its share. They include a property tax rebate, direct payments to households, lower water rates, a new community recreation center, downtown work and open space. She said these were things the village could not have taken on without raising taxes or borrowing.

Marin gave different figures to the Scanner in August. He said the project would create more than 1,600 jobs and well over $1.5 billion in new taxes and fees. The village fact sheet estimates 1,200 to 1,600 operations jobs,. The village's $1.4 billion is property tax revenue only.

Where the Record Disagrees With Itself

How big is it? The village fact sheet of August 25 says 473 acres and, under the latest plans, 6.75 million square feet in 11 buildings. It says that is 33 percent less building space than earlier plans. The Scanner and the Daily Herald still describe the approvals as up to 472 acres and up to 10.1 million square feet in up to 18 buildings. Chronicle Media reported more than 400 acres and 20 buildings.

When was it approved? The village fact sheet lists data center approval meetings from September 23, 2024 to May 6, 2025. The Daily Herald and the Scanner give the same span. Chronicle Media said the village board approved it in March 2025.

How much power? The village fact sheet gives no figure. The Scanner's account of the lawsuit says about 1.55 gigawatts from ComEd.

When does $100 million a year start? The village fact sheet says after the first 20 years. In her September 28 video, Davies said at full buildout.

Was the wetlands request suspended or withdrawn? The Scanner said suspended on August 8. The Scanner on September 1 and CBS Chicago said withdrawn. Davies said removed. The village fact sheet says the developer put a halt to it.

State Pressure

State Rep. Daniel Didech, a Democrat from Buffalo Grove, said the project "should not proceed" if information he requested is not promptly shared with the public, the Scanner reported on August 30. He also criticized the village's limit of 15 minutes of public comment at future meetings. He plans to push the POWER Act in the fall veto session.

The village set out its approach in an August 17 press release. It scheduled a one-time public comment session on the data center for August 20. It said the project would not be on upcoming board agendas, and that comment on items not on an agenda would return to a 15-minute limit. It also added screening at the door and a ban on bags at board meetings, citing law enforcement concerns. On August 19, the village postponed the August 20 session, citing safety concerns tied to social media posts.

Timeline

Why It Matters for Site Selectors and Developers

A county pause covers only the land the county controls.

A developer outside Lake County's villages faces a pause that runs to May 11, 2027, unless rules come sooner. A developer in a village needs that village's approval, and a court can be asked to review it.

The lawsuit lists the grounds opponents are using: notice that did not name the use, a zoning code with no data center category, and open meetings rules.

The Risks and Obstacles

The lawsuit is open. The plaintiffs want the approvals declared invalid and the development agreement voided. The village has filed a motion to dismiss. The October 30 hearing is a first status date.

The wetlands request could return. The developer has halted or withdrawn it. No source says it cannot be filed again.

The county rules are not written. The pause ends May 11, 2027, unless the board adopts rules first. What those rules say is not yet known.

The numbers do not agree. Acres, square feet, power and approval dates differ by source, as listed above.

The state bill is not law. The POWER Act is a proposal. Representative Didech plans to push it in the fall veto session.

What to Watch

• The October 30 hearing in Lake County Circuit Court and any ruling on the village's motion to dismiss.
• Any new request to the Army Corps of Engineers to fill wetlands at the site.
• The Lake County Board's draft data center rules before May 11, 2027.
• The fall veto session and the POWER Act.
• Grayslake's decisions on a recreation center, downtown and open space projects, and how each taxing body plans to use its share of the new revenue.
• Whether Grayslake issues permits for more buildings after the first 800,000-square-foot building.

This article is factual background and is not legal, financial, or investment advice.