City planners present draft data‑center zoning rules as residents and industry spar over limits

City planning staff presented a comprehensive draft of zoning and operational rules for data centers in St. Louis at the committee’s June 22 meeting, proposing a three‑tier approach intended to tailor requirements by facility size and potential impact.

The planning commission‑backed draft would create a new zoning chapter that classifies data centers as micro, standard or major facilities based on square footage and maximum power demand, require conditional‑use review in all zoning districts, and impose site, noise, water and renewable‑energy conditions intended to protect neighborhoods and infrastructure.

Miriam Keller, City Planning’s executive for general planning and design, said the rules distinguish three tiers: micro facilities (small, limited power demand), standard facilities (intermediate scale) and major facilities (the highest tier, subject to the strictest limitations). The panel would treat data centers as conditional uses in every district to ensure site‑specific review; major facilities would be limited to the city’s most intensive industrial districts, the staff recommendation said.

Staff also proposed mandatory application disclosures including anticipated maximum power demand, water use, project end users, financing, timelines, decommissioning plans, and commitments for renewable energy and community engagement. Setbacks would scale with facility size (proposed at roughly 150/300/600 feet for micro/standard/major), and the draft bans evaporative cooling as a sole cooling solution, citing large water consumption.

A large public turnout reflected the polarizing nature of the topic. Environmental groups and neighborhood advocates urged a mandatory community consent mechanism for the largest facilities and called for stronger renewable‑energy build‑out timelines and air/water safeguards. Elise Schaefer of Missouri Coalition for the Environment urged that renewables and monitoring are necessary to prevent increased fossil‑fuel generation tied to big data center demand.

Industry speakers and downtown stakeholders argued the draft risks harming existing facilities and undermining downtown reuse. Representatives of existing downtown data centers and service providers said new triggers (notably a proposal to forfeit grandfathering when backup‑generator capacity increases) could render lawful operations nonconforming and create legal exposure, and asked for clearer grandfathering and expansion rules. Developers and union representatives urged flexibility to allow investment and job creation, particularly downtown.

Several unions and economic developers argued data centers can produce tax revenue and new, well‑paid construction jobs; neighborhood groups countered that the long‑term environmental and public‑health tradeoffs (noise, low‑frequency vibration, generator testing, heat, and air emissions) warrant tighter local limits. The planning presentation and the committee record show the proposal remains a trade‑off between those priorities.

Planning and committee members agreed the draft is imperfect and needs follow‑up work. Staff said they would refine technical sections, monitor legal applicability (including how to treat existing facilities as ‘nonconforming’), and work to align the draft with the comprehensive zoning update under way. The committee expects to continue the data‑center discussion at a future meeting and flagged several areas for amendment and clarification, including grandfathering treatment, the role of maximum power demand (megawatts) versus square footage in defining tiers, and possible community consent mechanisms.

No committee vote was taken on Board Bill 49 at the meeting; the measure will return for further committee consideration.