Washington, D.C.'s largest suburban county has set new limits on the size of data centers and their proximity to residential neighborhoods and transit stops as the industrial facilities spread.
The board of supervisors in Fairfax County approved a rule that data center buildings must be at least 200 feet from residential property and a mile from Metro stations. The county, with 1.1 million residents as of 2023, also capped data center size at 80,000 square feet in certain areas zoned for industry. Developers have to ask the board for permission to exceed these restrictions.
Cities across the country are concerned that data centers, while providing substantial tax revenue, may pop up in the wrong locations. Atlanta’s city council recently considered a ban on new data centers near walking trails and transit stations out of concern the industrial facilities will compete with other types of employment and housing.
As of February, Fairfax had more than 4.4 million square feet of data centers under construction, on pace to more than double what already exists, according to a report by the Northern Virginia Technology Council. Data centers across the county range in size from 30,000 to 500,000 square feet.
Nearby Loudoun County leads the region with more than 30 million square feet of data center space built, while Prince William County has 7 million square feet built and 30 million more under development, the NVTC report said. Across greater Washington, D.C., data centers play a large role in industrial development, according to a CoStar report.
“We did this because it’s in our interest to get ahead of a problem that exists in the jurisdictions around us,” Jeffrey McKay, the Fairfax board chairperson, said before the Sept. 10 vote. “One of my colleagues in a neighboring jurisdiction [told me], ‘I wish we’d done what you’re doing 10 years ago, before the data center boom happened.’ We want data centers, but we want them under the right conditions, and to protect the neighboring communities around them.”
Added requirements
Loudoun officials introduced legislation this year that would allow them to reject any data center project, even if it’s proposed in an industrial zone and meets other county standards.
The board vote also requires data center developers to submit noise studies before and after construction to address concerns about the sound effects of the facilities’ cooling systems on nearby neighborhoods. Besides the 200-foot setback from housing, the board approved a 300-foot setback from ground-level data center equipment unless it’s separated from residential areas by the data center building.
The 80,000-square-foot size limit the board added for the I-4 industrial zone previously applied only in lower-density industrial areas.
The minimum distance from Metro stops is necessary to leave room for housing and employment centers near the stations, Fairfax County staff wrote in a May report before the planning commission considered the draft rule. Until the board vote, the setback for data centers from residential property was equal to the height of industrial buildings, typically at least 40 feet.
In addition to creating pressure on residential areas, data centers use a significant amount of water and electricity. Fairfax’s planning commission voted in June to have the county coordinate land use decisions more closely with area electric and water utilities. According to a county staff report in May, a typical 400,000-square-foot data center demands up to 60 megawatts of electricity, while a 250-house subdivision needs a single megawatt.