Board approves $250 million cost increase for Silver Line extension

The long-delayed extension of the Silver Line into Loudoun County will cost $250 million more than first anticipated — a cost that will largely be shouldered by Dulles Toll Road users.

At a meeting yesterday (Wednesday), the Metropolitan Washington Airports Authority board approved the cost overrun — including $188 million through tolls on the Dulles Toll Road.

The increase was driven by an increase in the complexity of the project, costs for materials, supply chain issues, and COVID-19-related issues, according to Andrew Rountree, MWAA’s chief financial officer.

Rountree also pointed to the project’s complexity at all levels, new environmental regulations related to stormwater management, and changes in the overall scope.

The cost overrun pushes the budget from $2.79 billion to a little over $3 billion.

Still, Rountree says the increase will not affect tolls directly, which are already expected to go up this year, because MWAA was able to restructure a loan to “flatten out” debt service from 2033 to about 2044.

Fairfax County will pay $40 million, Loudoun County will offer $12 million, and MWAA will recover $10 million.

Drew Hascall, vice president of MWAA’s Office of Engineering, said many of the cost increases are expected given that the project is four years behind schedule.

“We’ve gotten to the point where we’ve resolved all those unresolved requests or changes and we’re closing it out,” Hascall said, adding that contract closeout is expected once the additional funding is obtained.

Metro — which assumed control over the rail extension in late June — still hasn’t set an opening date for the 11.4-mile extension of the Silver Line into Loudoun County, but a fall opening is anticipated.