PowerHouse and Hillwood: The Joliet Technology Center and the $20 Billion Rezoning Now in Court

The Joliet plan rezoned 795 acres of farmland at the edge of the city from agricultural to light industrial and annexed it, clearing the way for 24 buildings totaling 6,936,000 square feet and a power demand of 1.8 gigawatts. The Plan Commission heard it on March 5, 2026, the City Council took it up on March 16 and March 19, and the council approved the annexation agreement 8 to 1 on March 19.

The plaintiffs allege the rezoning bears no substantial relation to public health, safety, or welfare and is therefore unconstitutional under Illinois law, that the city violated the Illinois Open Meetings Act, that the February 18, 2026 public notice never described a data center, and that residents were denied the chance to cross examine witnesses. They ask the court to void the March 19 vote.

The defense is specific and, so far, undecided. The city argues the February 18 notice adequately described the project through its industrial classification and its name, and that state law does not require a notice to specify a project's end use. The developers' attorney argues the plaintiffs had no right to cross examine witnesses at the March 16 meeting because it concerned an annexation agreement, that the right belongs only to property owners within 600 feet, and that the meeting video shows no one sought it. On the Open Meetings Act, the city says nullifying a vote taken at an open public meeting is too extreme a remedy for an alleged notice or agenda defect. The defendants also challenge the nonprofit's standing because it was incorporated on June 4, after the suit was filed. Our full report on the Joliet case has every filing and the September 8, 2026 motion hearing.

The developers have made their case in public as well as in court. Through Hillwood, they have said the campus would generate $2.1 billion for all taxing bodies, including schools and other units of local government, over 30 years, would create between 7,000 and 10,000 jobs through construction, and would support 700 permanent high paying positions once fully operational. Shaw Local reported those figures and also reported that the city, Hillwood, and PowerHouse Data Centers did not respond to its requests for comment on the lawsuit itself. The city's spokesperson said the city does not comment on pending litigation.

Those promises are the ordinary currency of a hyperscale approval, and they are exactly the terms residents should push to see written into an annexation or development agreement rather than a press release. Our tax abatement guide explains how to read a 30 year revenue projection, and our guide to who pays for data center power covers the 1.8 gigawatt half of the equation.

Joliet is not the only front. The same plaintiffs' firm is challenging a 472 acre campus in Grayslake on a similar theory, and the reason both cases exist is Prince William County, Virginia, where the largest data center approval ever granted was voided because the hearing notice was legally defective. The Joliet defendants are asking an Illinois court to draw that line in a different place, holding that a zoning category and a project name are enough. Whichever way it goes, the ruling will govern how every large campus in the state is noticed and approved.

If a project near you moved from first hearing to final vote in a matter of weeks, the practical lesson from Joliet is to pull the published notice and read it for what it does not say, to request cross examination in writing at the hearing whether or not you live within 600 feet, and to make sure individual neighbors are named alongside any group. Our guide to fighting a proposed data center and our zoning appeal deadlines guide cover the substance and the clock. Our free case review connects you with an independent attorney in our network who handles data center cases in your state, at no cost and with no obligation.