Franklin County hears wide public reaction to proposed data‑center regulations; staff proposes setbacks, noise limits and utility verification

Franklin County planning staff presented proposed zoning amendments on Jan. 20 to regulate data centers, and the Planning and Zoning Commission opened an extended public‑comment period that produced sharply divided views.

Staff summary: Planning staff (Nicole) proposed definitions for “data center” and “accessory data center,” to permit data centers in G and A zoning districts subject to Article 10 regulations. Key proposed requirements included a 400‑foot setback from all property lines for buildings and associated equipment, a 1,000‑foot setback from property lines adjacent to highly residential districts, a maximum site footprint of 800 acres and a maximum structure height of 100 feet (including antennas). Screening and lighting would follow Article 13 standards; outdoor lighting would be downcast and mounted no more than 20 feet above finished grade. Security fencing would be required (ornamental wrought iron or similar, 6–12 feet tall; barbed/razor wire prohibited), and security guard structures would be exempt from setback requirements.

Noise, utilities and verification: The draft sets daytime noise limits at 60 decibels (7 a.m.–10 p.m.) and nighttime limits at 50 decibels (10 p.m.–7 a.m.) measured at external property lines. Staff would require pre‑ and post‑development sound modeling, mitigation plans if levels exceed thresholds, a post‑development study within 90 days of each phase and then every three years thereafter. Utilities and infrastructure provisions call for at least two access points from state or county roads and service by public water and sewer where available; developers may build systems to agency standards if municipal service is absent. Staff also proposed written verification from the electric utility that the system can safely support the facility and suggested limiting fuel deliveries to 10 a.m.–4 p.m.

Commissioner discussion: Commissioners debated mandating closed‑loop cooling systems, fence‑rating language (sturdiness vs. specific ornamental material), and whether to require utility contract verification for projects near or above a 75‑megawatt threshold (the Public Service Commission of Missouri contract requirement for large projects was noted). Application‑fee proposals discussed ranged from $1,500 (staff idea) to $10,000 (commissioner suggestion) to cover additional review work.

Public comment: The meeting drew dozens of residents, local labor representatives and outside developers. Supporters — including a data‑center developer representative and the chairman of the Franklin County Labor Committee — emphasized construction jobs and economic development; the labor representative said data centers are “clean” facilities and urged closed‑loop cooling and local hiring. Opponents raised water‑use, noise, wildlife, electromagnetic fields and grid‑capacity concerns. Residents presented an ongoing petition with 4,039 signatures opposing data‑center development near the proposed Old Diamond Farms / Gravois Summit area and asked for stricter setbacks, lower noise thresholds, more frequent sound testing and explicit protections for domestic wells and groundwater. Several technical speakers (electrical and mechanical engineers, water‑system professionals) urged mandatory closed‑loop cooling, hydrogeological surveys before any on‑site groundwater pumping, more frequent noise monitoring than a three‑year interval, and stronger utility and decommissioning assurances.

Status and next steps: No final action was taken; staff will incorporate feedback and commissioners signaled options to refine setback, noise, cooling and fee language before a future motion. The commission paused for a brief technical break at the end of public testimony to restore the livestream and accommodate overflow seating before resuming deliberations.