Golden to Mars

Golden to Mars is a pair of new overhead lines, one 500 kV and one 230 kV, between Dominion's Golden Substation near Route 28 and the W&OD Trail and its Mars Substation west of Dulles Airport. The same case approved two 230 kV loops, Prentice and Sojourner, and work at five substations. Dominion filed it with the State Corporation Commission on March 28, 2025, at a stated cost of about $513.1 million in 2025 dollars, with a target in-service date of June 1, 2028.[1]

Dominion said the project, with Mars to Wishing Star and Aspen to Golden, completes a 500 kV loop around Data Center Alley. No party disputed that the lines are needed. The fight was over how and where to build them.

What the SCC decided

On April 9, 2026 the SCC found the lines are needed and that burying them is not feasible in this case, citing timing, cost and construction problems. It approved Route 4, which needed the School Board's consent to cross school land, and named Route 3A as the fallback. The Commission found Route 3A puts nearly four times as many homes within 250 feet of its centerline as Route 4.

The School Board did not consent. On June 29, 2026 the SCC approved Route 3A, about 8.4 miles. It wrote that "by almost every objective measure, Route 3A is clearly inferior to Route 4," and approved it anyway, finding that "continued delay in ordering a final route for this Project unreasonably jeopardizes the provision of reliable electric service."[2] Route 3A follows the Broad Run stream valley and crosses Loudoun Reserve Drive at the entrance to Rock Ridge High School and Rosa Lee Carter Elementary.

The April 9 order also says something every Loudoun official should read. As data centers concentrate in one area, the SCC wrote, there may come a point where no reasonable transmission route is left, and it may need to look at whether the utility and localities should plan together, earlier.

Where it stands

The SCC refused to suspend its order on July 20, 2026. The School Board, Loudoun County and two homeowners associations have taken the fight to the Supreme Court of Virginia, the only court that hears appeals of SCC decisions. In early August the School Board was asking the Court to keep Dominion off the parcel it now owns on Route 3A while the appeal is decided.[4] We have not confirmed a ruling by the Court since then.

Who decides

The SCC decides whether and where a transmission line is built. The county does not. What the county does decide is how many data centers it approves, and those approvals drive the need for lines like this one.