The data center tradeoff

Background in two minutes

Loudoun is home to the largest concentration of data centers in the world, most of them in the Ashburn and Dulles areas. In the county's fiscal year 2025 budget, data centers produced about 38% of general fund revenue and nearly half of property tax revenue. Most of that comes from the computer equipment inside the buildings, which is taxed at $4.15 per $100 of value.

As of February 2025, county staff counted about 46 million square feet of data centers built or permitted, with roughly 61.5 million more square feet of possible development. Until March 2025, a data center that met zoning standards in industrial areas could be approved by staff without a public vote. Since then, every new one needs a public hearing and a Board decision.

The case for continued data center growth

Supporters point to the money. Data center revenue has let the Board cut the real estate tax rate and the car tax in back-to-back budgets while fully funding the School Board's request, and it produced budget surpluses of $259.6 million and $194 million in recent years.

They also argue that industrial land is the right place for industrial buildings. When the Board narrowly approved a data center near Leesburg Executive Airport in July 2025, the chair said the site was already industrial and an appropriate location. Industry representatives argue that changing the rules for projects already in the pipeline is unfair to companies that planned under the old ones.

The case for tighter limits

Critics argue that each new data center brings costs that don't show up in the budget. Residents who spoke at hearings raised noise, huge buildings near homes, and new high-voltage lines needed to power the growth, and many worry that grid expansion will raise electric bills for households.

Town mayors and residents backed the 2025 rule change because it lets supervisors judge each project on its own effects. Some supervisors now say the county relies too heavily on one industry and should plan for slower growth before it is forced to.

What the county actually did

The Board's votes show a county that has moved from automatic approval toward closer review, often by narrow margins.

• Mar 13, 2024Belmont Innovation Campus denied at 2.9 million square feet Denied Vote: 5–4
  Denies the original, larger version of the Belmont Ridge Road data center campus. A smaller version was approved a month later.
• Apr 10, 2024Scaled-back Belmont Innovation Campus approved Approved Vote: 6–3
  On reconsideration, approves a 1.3 million square foot data center campus on about 112 acres along Belmont Ridge Road.
• Mar 18, 2025Data center rules, Phase 1: ending by-right approval Adopted Vote: 7–2
  Requires special exception approval, with public hearings, for data centers in the IP, GI and MR-HI districts. Pending applications grandfathered in a separate 5–4 vote.
• Jul 15, 2025Cross Mill Center data center near Leesburg airport approved Approved Vote: 5–4
  Approves a data center rezoning at Crosstrail Boulevard near Phil Bolen Park, close to Leesburg Executive Airport.
• Sep 16, 2025Data center rules, Phase 2 project plan approved Approved
  Approves the Phase 2 work and adds a General Plan policy limiting data center encroachment into the Transition Policy Area.
• Apr 7, 2026FY 2027 county budget adopted at $5.4 billion Adopted Vote: 8–0–1
  Holds the real estate tax rate at $0.805, cuts the vehicle tax rate, fully funds the schools' $105 million increase, and raises public safety pay.
• Jul 23, 2026Spring Valley Technology Park recommended for denial Denial recommended Vote: 6–0
  A 325-acre campus near Beaverdam Reservoir proposing 12 data centers and three substations. The Board of Supervisors makes the final decision.
• Sep 2, 2026Review of 2025 grandfathering exceptions requested Legal analysis requested Vote: 9–0
  Asks staff for legal analysis on ending the 2025 grandfathering resolution, which covers 17 applications totaling about 11 million square feet.
• Sep 15, 2026Proposed pause on data center and substation application votes Vote Oct 20
  A resolution would pause final votes on legislative data center and substation applications for up to 12 months, retroactive to Sept. 15. Scheduled for consideration Oct. 20, 2026.
• Sep 28, 2026Data center rules, Phase 2: noise, power and substation standards Public input
  Covers noise, on-site generation, battery storage, substations and siting. Open houses held Sept. 28 and 30; staff recommendations to the Planning Commission expected February 2027.

Open questions

• Will the Board approve the proposed 12-month pause on data center and substation votes on Oct. 20, 2026?
• Will the 17 applications protected by the 2025 grandfathering resolution keep that protection after the county's legal review?
• What noise, power generation and substation standards will Phase 2 set when it reaches the Planning Commission, expected in February 2027?
• If data center growth slows, how will the county replace that revenue without raising other taxes?