As Project Blue continues to break ground near the Pima County Fairgrounds, the city of Tucson has been working on regulations to manage future large-scale data centers.
On Wednesday night, more than a dozen Tucson locals trickled into the city council chambers to share their input before the Planning Commission, as they reviewed a proposal to define large-scale data centers as well as operating standards for these facilities within city limits.
At first, the Project Blue property was expected to be annexed into the city, but those plans were halted when the city council denied the project access to city water. Project Blue is being built in unincorporated Pima County, so it is unaffected by city regulations.
The Commission made several recommendations to address concerns related to public health and noise levels, building setbacks and water usage – issues brought up during the public comment period.
Tucson resident April Putney asked for the committee tasked with creating the standards to define what qualified as an emergency, in the event that backup generators need to be turned on.
After the hearing, Putney told AZPM that she feels conflicted towards state-level restrictions that limit local decision-making.
“I think there’s a lot more that we can do in the state of Arizona to help protect our communities from large scale data centers and their harms,” Putney said.
The Commission will hold another public hearing for city staff to review those recommended changes in about 45 days.
The next step is to move the standards forward to the Mayor and Council for a hearing and review this summer.
Where the rule stands now
City officials are proposing to define large-scale data centers as:
Any facility, multiple facilities, or portion of a facility on a contiguous site with the same controlling ownership interest, and a gross floor area greater than 25,000 square feet or uses greater than 20 megawatts (MW) of energy, housing networked computer systems and/or telecommunications equipment used for remote storage, processing, and distribution of data.
A public review process is proposed with an enhanced public notification of all property owners within half a mile, neighborhood associations within two miles, a neighborhood meeting, Zoning Examiner public hearing and Mayor and Council decision.
Large-scale data centers would not be allowed anywhere by right. City officials said that these facilities would require a higher level of review than most land uses in the city with an ultimate decision by the Mayor and Council.
1. The proposed procedure for data center review is: 2. Neighborhood meeting 3. Application Submittal 4. Public Notice of Zoning Examiner Public Hearing 5. Zoning Examiner Public Hearing 6. Zoning Examiner Recommendation 7. Mayor and Council Decision
In addition to the process, city officials are also looking at establishing standards in the proposal:
- Noise limits at the property line, requiring sound walls or roof screening.
- Requiring battery backup first during power disruptions, prohibiting “load shifting” or running generators instead of grid power.
- Applicants using Tucson Water must comply with the *Large Quantity Water User Ordinance, must demonstrate adequate water supply, use no potable water for cooling if not covered by the ordinance.
- Applicants must demonstrate adequate energy supply at time of application and disclose energy use and mix including renewable energy.
- Landscape buffers of 40ft are being suggested as well as reduced parking requirements, a maximum 40% lot coverage to encourage greater open space onsite and the revegetation of disturbed land with native plants.
Tucson adopted the Large Quantity Water User Ordinance in August 2025 and requires any potential customer who plans to use 7,480,000 gallons of water or more per month to submit plans to the Mayor and Council for approval.
Additional changes have been made since last month’s Planning Commission study session including changing the lower energy threshold from 50MW to 20MW in large-scale data center definition, the establishment of a maximum height limit of 50 feet, increased separation from residential/ non-industrial uses to address concerns about noise and heat island effects and expanded landscaping and native vegetation protections.
Earlier this year, Tucson officials held four public meetings in February and March, to solicit community feedback.
About 200 participants shared concerns about water scarcity, energy demands and utility, setbacks from property lines and outright opposition to large-scale data centers within the city.
