Pima County ponders tougher data center rules

The proposed changes come shortly after new documents confirmed plans of another data center proposal in Sahuarita known as Project Gravel that has been in the works for at least a year.

County Administrator Jan Lesher released a memo Monday that includes the draft changes to the section of county zoning code addressing data centers.

Under the new code, the county would only allow developments that use a closed-loop cooling system, a more water-conscious method which recirculates the same water to cool computer equipment. The water in these systems can go several years without needing to be replaced or refilled.

Any development over 25 acres has to get approved for a conditional use permit, which the county uses for commercial land users that have the potential to be disruptive to the surrounding community.

The code adjustments also set new standards for height, setbacks from other properties, and noise. Developers would have to conduct a third-party noise study and comply with maximum noise levels that vary depending on the adjacent properties. If a data center development was next to a zoned residential area, noise levels would need to be under 55 decibels at all times, about as loud as a household refrigerator, according to Yale Environmental Health and Safety.

The county’s Planning and Development Services department published an online survey Monday that asks participants to rank major concerns about data centers and what mitigation techniques the county should require from developers.

Survey responses will be reviewed by staff to shape the version that appears in front of the Planning and Zoning Commission on Oct. 28, where there will also be a public hearing, according to Lesher’s memo.

The final changes are then scheduled to be considered by the Board at the Dec. 15 meeting.

There will also be an open house on Monday, Sept. 28 from 10:00 a.m. to 3:00 p.m. in the basement of the Public Works Building, 201 N. Stone Avenue.