The Ohio Supreme Court on Sept. 18 blocked a ballot measure that could have imposed new operating restrictions and citizen lawsuits on a planned $4 billion Amazon Web Services data center campus in Wilmington, about 35 miles southeast of Dayton.
The court denied a request by petitioners Quintin Koger Kidd and Susan Croutwater to require the Clinton County Board of Elections to put their proposed ordinance on the Nov. 3 ballot. A separate federal case continues over the zoning measures underlying the project.
The proposed ordinance would regulate noise, lighting, air emissions, generator testing, water use and discharge, and heat generation. It would also give certain nearby residents a “private right of action” to enforce those requirements against data center owners and operators.
The court held that the citizens’ enforcement provision exceeded Wilmington’s authority. “The proposed ordinance at issue here seeks to create a new cause of action and is therefore beyond the jurisdiction of the municipality to pass,” the court said.
Under the proposal, residents could seek court orders to suspend data center operations. Courts could also impose penalties of up to $10,000 per day, suspend a certificate of occupancy or revoke conditional use of the property, and successful plaintiffs could recover attorneys’ and expert fees.
The Wilmington Planning Commission remains unable to approve, conditionally approve or deny the AWS site plan under a separate federal court order. That July 14 order, entered into by agreement between Wilmington and the plaintiffs, bars that action until the city council ratifies, replaces or re-enacts three ordinances involving generator noise, data centers as a permitted use and rezoning of the project site, and those measures take legal effect.
The order also requires 14 days’ notice before the commission acts on the site plan and allows participants to present evidence and cross-examine opposing witnesses. Amazon Data Services, which U.S. District Judge Jeffery Hopkins allowed to intervene in the case in June, did not object to the July order but reserved its rights to the ordinances and its pending site plan application.
AWS and the Clinton County Port Authority did not immediately respond to ENR’s questions about the project’s current approval and construction status, whether the Supreme Court ruling affects their schedule and what work can continue while the separate litigation is pending.
Within the AWS Wilmington plans
AWS is proposing a nine-building hyperscale campus in the south end of Wilmington, which is located between Cincinnati, Columbus and Dayton. The city’s 1,900-acre Wilmington Air Park, 10 minutes off Interstate 71, is Ohio’s highest-volume cargo airport and a major regional logistics and distribution hub.
According to the Port Authority of Clinton County, the nine main AWS data center buildings will total about 1.92 million square feet, with individual buildings ranging from approximately 163,000 square feet to 220,000 square feet.
The Port Authority says AWS expects construction to take more than five years and create more than 200 jobs. A December 2025 economic development filing puts Amazon Data Services’ projected private investment at $4 billion, with at least 100 permanent jobs and an annual payroll of $8 million once operational.
The 471-acre site was annexed into Wilmington and zoned light industrial in August 2025. AWS selected the location in part because of its proximity to the Wilmington Wastewater Treatment Plant and the ability to extend water and sewer infrastructure to the property, according to the Port Authority.
Last March, Bohler, AWS’ civil engineering agent for the project, presented traffic, stormwater, photometric and noise studies to city officials.
The campus is designed with 252 Level 4 safety generators in acoustic enclosures with double-walled above ground or belly fuel tanks. AWS told Wilmington that each generator would run an average of about 10 hours a year for testing, maintenance and emergencies.
The infrastructure extends beyond the site
AWS is expected to build and pay for at least $25 million in public infrastructure associated with the campus, including 3.5 miles of sewer trunk, 2.5 miles of water channel and a 1 million gallon water tower. Road improvements on US 68 and State Route 730 must also be constructed and paid for by AWS to city and Ohio Department of Transportation standards.
Bohler’s site plan shows nine major data center buildings planned for Amazon Web Services’ 471-acre Wilmington, Ohio campus, along with a substation, water tower and stormwater facilities. Click on the image to enlarge it.
Courtesy of Bohler
The off-site healthcare system had reached 30 percent design in March, with calculations covering full construction of the AWS campus “as well as the ability to serve future upstream developments unrelated to this project,” Bohler said. The final sanitary sewer design was pending.
The planned water work includes replacing and upsizing an existing main along State Route 730 and widening the main along the northern boundary of the project to US 68. The 1 million gallon water tower is also intended to improve pressure for nearby customers, according to the Port Authority.
AWS estimates that the campus would use approximately 6 million gallons of water annually, with water needed for cooling about 11 days a year. As of March, the company was pursuing a water service agreement with Wilmington governing all water use on campus.
Bohler also told the city that the project’s general contractor would obtain Federal Aviation Administration approval for construction cranes closer to the start of construction. The file does not identify the contractor.
