Council adopts general‑plan policy and zoning rules for data centers after extensive public comment on power, water and fire risks

Phoenix City Council on July 2 adopted a general‑plan amendment and a zoning text amendment establishing location criteria, definitions and performance standards for data centers, after broad public comment and a unanimous council vote.

City staff and outside counsel told council that the scale and operational characteristics of modern data centers — very large electric loads, onsite backup generation, battery energy‑storage systems, and cooling systems — require a distinct regulatory framework that the current zoning ordinance does not address. Planning staff noted electric utilities APS and SRP reported interconnection requests from data centers that far exceed current system capacity, raising the prospect that some centers will need on‑site power and long‑duration energy resources.

The council approved a two‑part framework: a general‑plan policy to guide where data centers may be appropriate, and a text amendment that adds data centers as a listed use, defines the term, requires a special‑permit process and sets performance and siting standards. The Planning Commission had unanimously recommended the measures with modifications; staff proposed additional refinements in memos on June 26 and July 1 that the council accepted.

Key policy elements include a requirement for detailed technical analyses as part of future data‑center special‑permit applications — including grid interconnection plans, water usage assessments, fire‑safety plans and community impact studies — and a Prop‑207 waiver application process for property owners seeking relief from the new standards. Planning staff added noise limits and clarified exemption language for projects with existing final site plan approval. During debate the council emphasized transparency and public safety as central goals.

Fire and public‑safety witnesses urged stricter review. Chris Green, an energy specialist working with firefighters, described the difficulty of responding to a data‑center fire: “When those batteries have problems, those fires are extremely difficult to suppress even with water,” he said. Local firefighter representatives warned that large battery installations can produce intense heat and hazardous combustion products and urged explicit fire‑safety and notification requirements in the permitting process.

Industry and economic development representatives said the rules provide necessary clarity for investment but asked staff to preserve reasonable grandfathering for projects with binding utility agreements and preliminary site plan approvals. City staff and outside counsel said the July 1 memo addressed those concerns by clarifying exemptions and by setting a process for binding waivers of enforcement under Prop 207.

Both the general plan amendment and the text amendment were adopted by unanimous votes. Staff said the rules are designed as a pre‑application framework that will be applied to future special permits and major PUD amendments and that more technical review will occur at the special‑permit stage.