STATE TRANSPORTATION OFFICIALS plan to have South Coast Rail service up and running by November 2022, but they haven’t figured out a way to cover the $1 billion cost yet.

About $200 million has either been spent or budgeted so far, but the funding sources for the remaining $800 million haven’t been located. Officials say the Baker administration is working on a funding plan, but it won’t be ready until the end of the year – after the election.

Gov. Charlie Baker has made rail service between Boston and New Bedford and Fall River a top political priority, and officials within his administration say they are confident the money needed to get the service up and running will be found. But they haven’t been very talkative about where the money will come from.

The MBTA has a five-year, $8 billion capital plan (1999-2023) that doesn’t include the money. New Bedford and Fall River aren’t expected to kick in any funds the way Somerville and Cambridge did with the Green Line extension. And, at a joint meeting this week of boards overseeing the Department of Transportation and MBTA, Transportation Secretary Stephanie Pollack said she didn’t think the project would receive any federal funds.

So where will the money come from?

There are lots of theories. Some say the state’s bond cap – basically the amount the state can legally borrow each year – will keep growing and all or a portion of that increase could be siphoned off to help pay for South Coast Rail. Others say Baker will have to rob Peter (take money from other, currently funded projects) to pay Paul (cover the cost of South Coast Rail), although Pollack said at Monday’s joint board meeting that the boards didn’t want that to happen.

Rep. William Straus of Mattapoisett, the House chair of the Legislature’s Transportation Committee, said he doesn’t think it should be that complicated to find the $800 million in an $8 billion spending plan. He said the MBTA doesn’t need the money in one lump sum, and it’s not uncommon for some projects in a five-year capital spending plan to be delayed. Straus, a Democrat, said he is confident Baker, a Republican, will get the job done.

Asked if the governor should spell out his funding plan for South Coast Rail before the election, Straus said: “Whenever he does it, it’s fine with me.”

James Eng, MassDOT’s deputy administrator for rail and the person in charge of South Coast Rail, provided an update on the project at Monday’s joint board meeting. He said the T plans to complete design of the project by May 31, 2019, and spend $100.8 this fiscal year, including $10.6 million on special track materials that have to be ordered well in advance and $28.8 million on the purchase of nine properties.

Betsy Taylor, a member of the MassDOT board, raised concerns about signing contracts for South Coast Rail without a full spending plan in place. “If this project doesn’t go, can rail operations use these tracks at other places?” she asked.

Eng said the track could be used on other projects. He did not address whether the real estate purchases would make sense if funding for the entire project wasn’t found.

Joseph Aiello, a member of the MassDOT board and the chair of the T’s oversight board, wanted Eng to develop an estimate of what it would cost to operate and maintain South Coast Rail once it is up and running. 

It was an interesting line of questioning. Baker has made much of the T’s plan to spend $8 billion over the next five years, but even with that high level of spending a number of priority projects (South Coast Rail, Blue Line power and signal improvements, and Green Line rail car upgrades) aren’t currently funded. As Aiello’s question illustrated, the new spending in most cases also puts additional upward pressure on the T’s operating budget.

The hunt for money to fund South Coast Rail is probably a precursor of what’s to come.