The end result wasn’t perfect, Fairfax County supervisors acknowledged, but the zoning-ordinance amendment they passed Sept. 10 on an 8-2 vote was designed to protect residents from impacts of data centers.
The board pressed for the new rules “because we want to put in place protections for data centers in Fairfax County and not repeat the challenges that have been faced in neighboring Prince William and Loudoun counties,” said Board of Supervisors Chairman Jeff McKay (D).
Supervisors held July 16 public hearing on the matter and was scheduled to render their decision July 30, but had to hold a new public hearing Sept. 10 on this matter – and a host of others – because of a county legal-advertising snafu.
County code previously allowed data centers by-right in the:
• C-3 and C-4 office zones for facilities with up to 40,000 square feet of gross floor area, or larger if repurposing buildings that existed as of May 10, 2023.
• I-2 and I-3 industrial zones with facilities up to 80,000 square feet of gross floor area or larger if repurposing buildings that existed as of May 10, 2023.
Special exceptions were required in all the above zones for larger data centers or to increase their height or floor-area ratio (FAR).
• I-4, I-5 and I-6 industrial zones. There was no maximum size dictated, but data centers in these zones could be no taller than 75 feet and have an FAR of up to 0.5. Special exceptions were needed to increase FAR and height.
• PRC (Planned Residential Community), PDC (Planned Development Commercial) and PTC (Planned Tysons Corner Urban) zones, if shown on the approved development plan. Special exceptions were not applicable in these categories.
The new rules, which took effect Sept. 11, allow by-right data centers of unlimited size only in the I-5 and I-6 districts. The regulations remove the option for data centers in PRC districts, where no such facilities exist or are planned, and allow those in the PDC and PTC districts only by special exception.
Supervisors retained the previous size limits in the C-3, C-4, I-2, I-3 and I-4 zones and allowances for larger facilities by special exception. The board removed the allowance for larger data centers if buildings were being repurposed.
The board extended to all zoning districts requirements that data centers’ mechanical equipment, generators and power-supply equipment must be fully enclosed if feasible, or surrounded by a screening wall or other barrier if not.
Such equipment and accessory electrical substations, if located on the ground, must be screened from view by a visually solid wall or a building. That standard does not apply to solar-power equipment.
Data-center buildings or equipment must be at least 200 feet from the lot line of an adjacent or abutting residential district or property.
Data centers’ outdoor equipment and backup generators need to be at least 300 feet from residential lot lines or separated from the lot line of a residential-district property by the data-center building. Reduced setbacks are available via the special-exception process.
Data centers now must be situated no closer than 1 mile from a Metrorail station, unless a special exception is obtained.
The county government now will require data-center developers to submit pre- and post-construction noise studies to ensure compliance with the county’s noise ordinance. The new rules also require data centers to enhance their visual appeal using main-entrance features, façade variations and other architectural elements.
Site plans for data centers that were accepted for review by July 16 this year will be evaluated under the previous zoning ordinance.
The new rules are the first step toward addressing data-center challenges, supervisors said.
“Data centers provide job growth, economic opportunities and are an important revenue source that can be used to offset real estate taxes in the county,” Supervisor Patrick Herrity (R-Springfield) wrote afterward. “However, they need to be properly located and screened. While not exactly what I wanted, I supported the motion as a step in the right direction to achieve that balance.”
The General Assembly’s Joint Audit and Legislative Review Commission will provide a report by year’s end concerning the data-center industry’s impacts on energy demand in Virginia and how zoning and regulatory restrictions can affect development of those facilities, Smith said.
Supervisors also passed a follow-on motion directing the Department of Planning and Development (DPD) to review the energy-efficiency commitment of data centers, whether approved by-right and via rezoning or special exception.
County planners also will examine land-use and environmental factors related to data centers, including water quality and demand, air quality and noise.
The Department of Public Works and Environmental Services will monitor wastewater issues and concerns identified by Fairfax Water and the Upper Occoquan Service Authority.
Supervisor Walter Alcorn (D-Hunter Mill) said data centers should be powered by small, modular nuclear-fission reactors to avoid overburdening the electrical grid.
“That is absolutely critical,” he said. “We need to be out in front of that.”
Fusion reactors, which may be only a few years from reality, offer the “real promise of a whole lot of clean power,” he added.
Regarding the zoning-ordinance amendment, Alcorn said he would have preferred that all data centers be approved via special exception. He and Supervisor Andres Jimenez (D-Mason) voted against the main amendment, but the follow-on motion passed unanimously.
