It will take about 55 months (four years and seven months) to design and build the Green Line extension into Cambridge, Somerville and Medford.
Before that, it will take 24 months (two years) to relocate businesses that will be affected by land takings associated with the project.
And Green Line extension planners can't begin taking land until the project receives a certificate of no impact as part of the environmental assessment process. That certificate is expected sometime at the end of this year.
On top of that, and as part of Federal Transit Administration requirements for seeking New Starts funding, planners had to create a "risk adjusted schedule" to account for complications that could arise from uncooperative utility companies and bridge issues, among other things.
That, explained project managers at a meeting Wednesday night, is how the Green Line extension team arrived at June, 2019, as the date the new trolley line will be complete.
The project team expects the "design-build" phase of the project will begin in 2014.
"Our goal is not to be June, 2019; our goal is to be sooner than that," said Mary Ainsley, director of design and construction at the MBTA.
At the meeting, held at the near Union Square in Somerville, Katherine Fichter, manager of strategic planning in the state's Office of Transportation Planning, talked about a steering committee that will attempt to come up with ideas for moving the project along faster.
The steering committee will include a representative each from Cambridge, Somerville and Medford along with one representative from the Massachusetts Department of Transportation and one from the Federal Transit Administration, said Fichter.
Ainsley said the general manager of the MBTA hopes to have the steering committee in place in two weeks, and that it will likely hold seven meetings.
As of now, the Green line extension project is expected to cost $1 billion, and community advocates argue delaying the project will only add to the price tag, costing the taxpayer even more.
Federal New Starts funding would cover half the project costs, and in today's era of tight budgets, "We can't give up the opportunity to get half a billion dollars" of federal funding for the project, said Fichter.
As a result, the Green Line project team must adhere to the FTA's application process, which is "very strict," according to Ainsley.
And the project may never receive New Starts funding, a view held by at least one member of the public who said, "We are chasing ghosts … we're chasing things that are elusive and are not going to happen."
If the project doesn't receive New Starts funding, the state would have to authorize the issuance of a bond to cover the costs of the project. (One transportation bond of slightly over $600 million has already been authorized, said Fichter, but a new bond authorization would be required for the difference.)
And then there's the operating costs. Once built, the Green Line extension will cost about $22 million a year to operate. That's money the cash-strapped MBTA doesn't have and isn't expected to pay for.
Instead, the state will pay those operating costs.
Where does that funding come from?
"The exact mechanics of it we don't know yet," said Ficther, who added there are multiple possibilities at this point for authorizing that funding.
Upcoming public meetings
There are several upcoming meetings related to the Green Line extension.
A meeting about the a multi-use path for pedestrians, bicyclists, dog-walkers and others that is being planned in conjunction with the Green Line extension, will be held in September.
A meeting about the Green Line maintenance facility, in the Inner Belt area of Somerville, will be held in September.
A meeting about the environmental assessment will be held in October.
A series of three to four meetings about right-of-way retaining walls and noise and vibration mitigation will be held in October and November.
A series of three to four meetings about stations will also be held in October and November.