A portion of the Wiehle-Reston East Station is seen during a tour of the Silver Line in November 2013. (Matt McClain/The Washington Post)

The drivers have been preparing since September, testing new bus routes in the Dulles corridor, exploring the bus bays at the Wiehle Avenue Metro station garage, and familiarizing themselves with the other four new stations to debut this year as part of the first phase of Metro’s Silver Line. Now all they need is for the service to begin.

“We wait and wait and wait,” said Christin Wegener, operations manager for planning and customer service for the Fairfax Connector. Bus operators are getting extra training, the county’s outreach plan is being fine-tuned, “we have been looking at the schedules more carefully, looking at bus bay assignments . . . we are proofing timetables like mad,” she said.

Fairfax County finalized plans in June to start 15 new bus lines and adjust 28 others to increase transit ridership and encourage the use of the Silver Line when it opens. The county purchased 15 buses at $455,00 each. The Connector hired 35 new drivers and scheduled training, aiming for a launch at the turn of the year. But two weeks into February there is still no date for the start of passenger service on the Silver Line.

The first phase of the $5.6 billion Silver Line — four stations in Tysons Corner and one in Reston — was originally set to open in late 2013. A series of delays, including a software problem linked to the automatic train control system, pushed that timetable back. But the Metropolitan Washington Airports Authority, which is overseeing construction of the rail extension, could hand over the project to Metro this month. Metro would then determine when to begin service.

“We all want the line to be safe and so nobody is going to push to short-circuit the testing of the line,” said Fairfax Supervisor John C. Cook (R-Braddock), who serves on the Northern Virginia Transportation Commission. “We want to be patient with the process, but of course we are looking forward to the service starting because, yeah, it is part of a bigger effort to move people.”

Transportation planners have been busy over the last year remapping many of the biggest bus routes in Northern Virginia. Some jurisdictions, like Fairfax, have approved significant funding to boost service intended to complement the new Metro line and have already invested in new buses and manpower.

Fairfax County, where most of the changes will take place, budgeted $3.3 million for the first six months of new and adjusted bus operations, starting Dec. 31 of last year. The county is expected to spend about $6.5 million annually on the new service, with most expenses coming from a new circulator bus service in Tysons Corner.

Arlington, Loudoun and Prince William counties also are planning changes to accommodate the new line, including adjusting existing bus routes and adding new ones.

For some riders, the changes will mean shorter bus rides to Metrorail. For example, residents in Loudoun and Prince William counties who now take buses to the West Falls Church Metro station will instead be able to take buses to the new Wiehle Avenue station.

The Silver Line, one of the largest public transit projects in the United States, is expected to change the way people travel in Northern Virginia, where a vast majority of residents rely on cars to commute, and local governments are working to make the transition easier.

“It has been in everybody’s mind ever since the project went under construction,” said Nancy Gourley, chief of transit and commuter services in Loudoun County. Loudoun has purchased new buses, will launch one new bus line and will reroute two current bus lines to the Silver Line. It also plans to boost the frequency of service.

Some local transit systems are preparing to gain riders on some of their busy bus lines. Arlington is projecting that some of its buses serving north and central Arlington will feed riders who work in Tysons Corner to the Silver Line at Ballston and East Falls Church Metro stations.

“We are excited about it,” said Stephen Del Giudice, transit bureau chief for Arlington County. “The connection of our system to the Silver Line will boost hopefully the ridership and help us get people on transit rather than driving out I-66, which is what many of them probably do today.”

The county’s transit system, ART, is expecting to receive six new buses in the next few weeks and it is planning to launch the Route ART 43, between Crystal City and the Rosslyn-Ballston corridor, at the end of March. The new bus service was planned to address projected cuts in Blue Line service once the Silver Line opens. Del Giudice said the county expects the Silver Line to open around that time but that it will assess whether to delay the ART 43 launch.

More delays may prove costly to some Silver Line stakeholders. Metro, in particular, was counting on the Silver Line revenue as part of its current budget projections. Each month of delay in passenger service costs Metro $2 million to $3 million in lost revenue, according to the transit agency.

Metro also planned adjustments to 11 Metrobus routes in anticipation of the new rail line. All but three routes have been implemented, with the remaining three to change when the rail line opens, the agency said.

In Fairfax, the Silver Line bus plan affects about 40 percent of the Connector’s bus lines and is one of its largest undertakings ever. The county is not expected to take a big financial hit because of the delays.

An agreement with its transit provider, MV Transportation, includes $335,602 for start-up costs for new bus service associated with the Silver Line, including the hiring of new drivers, supervisory staff and new employee training.

Fairfax County is picking up other costs for time and resources that county staff members put into Silver Line planning and is working with Metro and MWAA to get the project moving.

“There has been a lot of preparation done and we are ready to go, but we obviously have to wait until the line can open,” Cook said. “It’s only been a couple of months, but if the delay continues we will need a pretty good explanation so people know what is going on.”

In Tysons Corner, a circulator bus service will connect the rail stations to key employment sites and shopping destinations. The service is viewed as an important investment in Tysons, which is primarily a commercial destination but is projected to grow dramatically after the Silver Line opens. The county predicts that the population of Tysons, now fewer than 20,000, will grow to 100,000 by 2050, and officials and developers hope to transform it into a walkable community where people live, work, shop and play.

“Until Tysons becomes pedestrian friendly we really think it is important to provide highly frequent bus service to connect people from rail to their location,” Wegener said.

County transportation officials say they hope the Silver Line will trigger changes in travel patterns in the area. By starting with a lot of service, Fairfax hopes to help the new rail line be successful and to encourage Tysons commuters to choose public transit.

“We are going to see how it goes,” Wegener said. For now, she said, “everything is hinging on the Silver Line opening.”