Metro riders who use the Silver Line's future stop at Washington Dulles International Airport may have to pay an extra surcharge on top of their regular fare if Loudoun County officials get their way.

It's unfair that Loudoun alone will have to pay for the upkeep of the airport stop, since so many D.C.-bound travelers will be using the station, Loudoun Supervisor Matt Letourneau said at a meeting of regional leaders Wednesday.

"It's a continuing source of frustration to Loudoun that we'll be paying the operating costs at the airport station," he said. "It didn't seem all that logical that Loudoun County be on the hook for that because most people who are going to board at Dulles airport are going east. They're going into D.C., not to the two stations in Loudoun."

But Mary Hynes, who sits on the boards for both Arlington County and Metro, said that instead of Metro organizing the surcharge, the Metropolitan Washington Airports Authority, which is overseeing construction of the $6 billion Silver Line, should take the reins.

"My understanding is that that is entirely under control of the MWAA board, whether they are willing to put that kind of surcharge on or not," she said.

Hynes suggested that the airports authority could charge Dulles travelers an extra $1 in their ticket price to pay for the station upkeep.

But Hynes also said that if Metro were to add a surcharge at Dulles, Ronald Reagan Washington National Airport should get one, too.

"National Airport's in my jurisdiction, so if we were to go that way, it should be both airports and not just one airport, in my opinion, because Arlington's been paying for 35 years for all of those passengers," she said.

Metro has discussed putting special 5-cent surcharges at stations like Union Station, where floods of riders have overwhelmed existing facilities, but it has never contemplated a surcharge as high as Loudoun might want, she said.

The Loudoun representative's lament about the cost of the Dulles station comes after the chairman of the Loudoun board, Scott York, recently complained that Fairfax County was seeking state funds to pay for part of its share of the Silver Line project, a move York said seemed unfair.

The first part of the Silver Line, to Reston, is expected to open to riders late this year. The second part, to Loudoun through the airport, is not expected to run until 2018.