Aurora council advances sweeping data-center rules after weeks of resident complaints

City of Aurora staff presented a package of four interrelated ordinances on March 18 designed to regulate data centersoperational transparency, sound and vibration impacts, energy and water use, and local privacy protections.

The measures would add two new chapters to the municipal code (an Aurora Responsible Data Center Ordinance and a Data Center Privacy Protection Ordinance), create a zoning text amendment to treat data centers as a distinct conditional use rather than simply a warehouse, adjust warehouse zoning rules, and update the building code to require city-reviewed sound and vibration testing before occupancy.

"We're distinguishing data centers from warehouses, creating performance requirements and requiring annual public reporting," John Curley, the city's chief development services officer, told the Committee of the Whole. He described requirements including engineered sound and vibration studies submitted with entitlement requests, city-selected third-party in-place testing before certificates of occupancy, annual public reporting of noise, energy and water, and development agreements that can include site-specific operational terms paid for by the developer.

Allison Lindbergh, the city's director of sustainability, summarized technical targets staff proposed: a challenging but achievable 1.2 Power Usage Effectiveness (PUE) target, a 0.2 Water Usage Effectiveness (WUE) goal or alternative compliance such as local battery-storage investments, a prohibition on potable-water evaporative cooling, limits on generator testing, and continuous reporting through a publicly posted EnergyStar Portfolio Manager account.

"This ordinance is about transparency and operations," Lindbergh said. She described annual third-party day-and-night noise testing, a developer-reimbursed city-selected testing engineer, and fines for failures to report.

The privacy measure would mirror Illinois' Biometric Information Privacy Act (BIPA), requiring written consent for biometric collection, retention limits and destruction, and a local annual certificate of compliance. Chaojun Liu of the Electronic Frontier Foundation told the council that protecting biometric data through a local ordinance "mirrors and reinforces" the state law and helps prevent corporate misuse.

Residents who live near existing centers pressed the council to go further, describing persistent noise and vibration they say have harmed sleep and quality of life. "They've been kicking the can forever," said Leo Wright, who said he lives about 1,500 feet from a data center and reported repeated, loud generator and chiller noise. Multiple speakers presented decibel readings and urged the council to tighten separation distances and lower allowable decibel levels.

Council members and city legal staff debated how strict separation distances can be without creating exclusionary zoning that could trigger legal challenge. Staff warned that strictly limiting districts where data centers can locate could effectively prohibit the use and risk litigation; legal counsel cautioned the council about measures that are "legal on paper but exclusionary in practice." Council members requested revised maps showing the effect of different setback distances and asked staff to model the results.

On testing and enforcement, staff proposed limiting generator maintenance/testing windows (9 a.m. to 5 p.m. weekdays, non-holidays) and allowing no more than two generators to be tested simultaneously for new facilities; staff also proposed city-selected post-construction testing reimbursed by developers to verify modeled performance matches in-place noise and vibration.

Council did not vote on the ordinances that night. Instead, members agreed to place the four linked files on unfinished business for the March 24 city council meeting, asked staff for updated maps and financial/context materials (including utility-tax and property-tax revenue estimates by megawatt), and confirmed staff can use a 30-day moratorium extension (available under the existing moratorium) if needed to avoid a regulatory gap. The extension would push the moratorium expiration to April 23 if invoked.

The package aims to balance resident protections and legal defensibility: staff signaled the city is seeking standards that are measurable at the data-center property line (auditable by the public and by staff) while preserving a conditional-use process and development agreements to address site-specific conditions.

Next procedural steps: staff will supply updated buffer maps showing the effect of alternative separation distances, provide additional decibel modeling examples tied to real parcels, and publish the staff FAQ and other materials online. The council will consider the ordinances again March 24.