Study and Review Committee reviews draft Oldham County data‑center rules, asks staff for another draft

The Oldham County Study and Review Committee on a June 2025 meeting reviewed a draft ordinance (proposed section 2‑53‑40) that would regulate data centers countywide and asked planning staff to revise the draft and return with another version for further consideration.

The committee’s review came after three months of work by county planning staff; Ryan Fisher, planning staff, told the committee the draft is intended to define and control data centers “to minimize their impact on surrounding properties, ensure compatibility and promote sustainable development.” Fisher said the regulation is still a draft and remains subject to change at the committee, the planning commission and the legislative bodies.

Committee members and members of the public raised questions about technical thresholds, setbacks, noise, generator testing, decommissioning and public notice — issues Fisher said the draft attempts to address but that may require more detail. ‘‘Power and energy are not the same thing,’’ resident Stuart Robinson warned the panel during discussion of size and energy thresholds, saying the facilities can approach the scale of power plants. Resident Don Erler asked that transmission lines be buried and substations screened, saying, ‘‘They should all be underground and the substations should be fully screened.’’

The draft classifies data centers by size and electrical capacity and ties those classes to where the use would be allowed. Under the chart in the draft: small centers are 5,000–20,000 square feet with 1–5 megawatts; medium centers are 20,000–100,000 sq ft with 5–50 megawatts and would be limited to industrial zoning (I1, I2, IPD); large or ‘‘hyperscale’’ centers are greater than 100,000 sq ft or greater than 50 megawatts and would be limited to I2 and IPD districts. Fisher said the draft includes a note recommendation to treat whichever measure (floor area or power) is greater as controlling so a small building with unusually high power demand would follow the large‑center rules.

Setbacks and siting: the draft preserves existing dimensional standards for C4, I1, I2 and IPD zoning but adds one new requirement: any structure, maintenance equipment, ground‑located cooling/ventilation or backup power equipment must be located at least 1,000 feet from buildings on adjoining properties used or zoned for residential purposes; the measurement is from the data‑center building or equipment to the adjoining residential building, not lot line to lot line. Fisher said that standard was modeled on existing Oldham County provisions for solid‑waste transfer facilities and similar rules in other jurisdictions; commissioners raised concerns that a strict 1,000‑foot rule could be effectively prohibitive in some industrially zoned areas.

Noise, mechanical screening, and testing: the draft would require pre‑construction and post‑construction noise impact studies signed by a licensed acoustical engineer, with an apparent target of no greater than 55 decibels at the property line for ongoing operations and a special allowance for short‑duration generator testing. Generator testing would be limited in frequency (no more than once per week per unit) and duration (the draft limits some testing to 15 minutes) and would be prohibited during specified daily hours; backup generators are required to meet a minimum emissions standard (‘‘Tier 4 or the highest standard available at the time of application’’). The draft also requires mechanical equipment to be screened from public roads and adjoining parcels and calls for sound‑dampening screening walls at least 10 feet high or at least two feet above the generator height, whichever is greater.

Power, cooling and green infrastructure: the draft allows diesel backup generators and battery energy‑storage systems and prohibits natural‑gas turbines for primary power generation. It encourages (but does not mandate) participation in heat‑recapture or thermal‑energy districts and recommends closed‑loop systems for liquid cooling equipment to avoid groundwater contamination. Fisher said the draft’s intent statements include promoting renewable energy and green infrastructure, though some provisions remain aspirational.

Security, fencing and surveillance: the draft requires perimeter fencing and prohibits chain‑link with razor wire; permitted fence materials were narrowed during discussion to metal options (aluminum or iron) and exclude vinyl and wood for these uses. Video, audio and drone surveillance must be restricted to an applicant’s property to avoid intruding on neighboring properties.

Impact studies and notices: the draft lists several impact studies that may be required, including noise (pre/post), traffic (after consultation with the county engineer), environmental assessments, and health impact assessments (with potential input from the Oldham County Health Department). The draft would require at least one neighborhood meeting at least 30 days prior to filing an application and formal notification to property owners within 500 feet of the proposed site, even if the parcel is already zoned for the use — a provision that drew questions about whether data centers are being treated differently than other industrial uses.

Decommissioning and financial assurance: the draft would define ‘‘cessation of operations’’ as 365 consecutive days of inactivity and would require a decommissioning plan within 90 days of permanent closure or 30 days after notice of abandonment. Centers larger than 20,000 sq ft would need to post financial assurance (bond, letter of credit, cash or escrow) sufficient to cover decommissioning and remediation; the county engineer would review and update the security every five years or after major expansions. Fisher said the requirement follows examples used elsewhere and noted enforcement experience and staffing limitations in the county.

Next step: after extended discussion and numerous suggested edits, committee members did not vote to forward the draft to the planning commission. Instead the committee requested additional revisions and another draft return to the Study and Review Committee before any formal transmittal. Earlier in the meeting the committee approved the May 22, 2025 meeting summary by voice vote.

The committee’s deliberations demonstrated the core trade‑offs county staff framed: protecting residential areas from noise, light and air emissions while preserving workable development standards for industrial property and accounting for long‑term decommissioning and public notice. Fisher and other staff said they will incorporate committee feedback and present a revised draft at a future meeting for additional review.