Metro is estimating it will cost about $107 million over the next three years to start what it is now officially ready to call the Silver Line.

Much has been made about the nearly $6 billion price tag for building the new 23-mile Metro line. But these additional costs are the first updated glimpse of what it will take to get the line running, including hiring workers to run the trains, clean the stations and fix the escalators.

It also marks the first time Metro is officially calling it the Silver Line, adopting its longtime nickname, said Metro spokesman Dan Stessel.

The Metropolitan Washington Airports Authority is in charge of building the new Metrorail line that will run from East Falls Church to Washington Dulles International Airport and into Loudoun County. But once the line is complete, Metro will take over.

Metro estimates the new line will cost $20 million in the next budget year, $43 million in the year the first section opens and $44 million after that, the transit agency said in a new report slated to be presented to its board of directors Thursday. The costs cover the transition expenses of recruiting and training rail operators, station managers, maintenance crews and other staff, the report said.

Those estimates, however, do not include any revenue brought in from fares when the first phase of the line begins to carry passengers, now slated for 2013.

Additional ridership and cost projections for the new line remain outdated. Metro officials have said they will provide updated estimates in the next few months.

It's also not clear how Metro will ask local jurisdictions to share the cost of paying the bills associated with the new service. The budget to build the line was divvied up among the communities that will benefit from it. But Loudoun County, for example, does not currently help fund Metro, nor does it have a seat on the Metro board, so new calculations must be made to see how much it should contribute in annual subsidies.

But one thing is now more clear: the name.

For years, it was called the Silver Line as a placeholder name.

Other possibilities, including "cherry blossom" pink or making the line a spur off the Orange Line, were suggested. But when Metro asked for public input this year, Stessel said, "the research was overwhelming" in support of Silver. Metro board members will be asked to sign off on the name this week as part of a package of revisions to the Metro map.