The MBTA’s Fairmount commuter rail line brims with untapped potential, for both the neighborhoods it passes through and for the region as a whole. The 10-mile corridor connects some of the poorest sections of Dorchester and Mattapan with downtown, offering a straight-shot ride to jobs and economic opportunity. For parts of the city that have long been under-served by public transportation, it could be an enormous asset if trains ran more frequently than the current 20 weekday round trips.
Transit planners see even greater potential. With its modern, high-level platforms that make boarding faster, the line is well suited to be the testing ground for a whole new vision for commuter rail in Greater Boston. The T’s control board voted last year to explore ways to transform the commuter rail system into a regional rail network that would operate more like a mass-transit system, with more frequent trains running at regular intervals behind clean locomotives, and tapped the Fairmount Line as one of the first corridors for that transformation.
That’s what makes this week’s announcement of new service on the line so exciting. The agency is adding eight trains daily, starting in May. It’s also providing a way for riders to pay with Charlie Cards on the platform instead of buying tickets on board, removing one of the practical barriers for passengers. That’s good for riders and builds off the hundreds of millions of dollars in state, philanthropic, and private-sector investment in the line. Improvements in the last decade include four new stations, a reduction in fares to attract more riders, and a recent extension to Foxborough. The eight extra trips will cost the T around $1 million a year and are expected to carry at least 185 new riders a day.
As important as the local benefits the new service will provide in Dorchester certainly will be, the model that the T is building may be more significant. With the region choking on traffic, improving the rail system is a must. Getting more riders out of cars and into trains — and making those trains cleaner — will also help reduce the state’s greenhouse gas emissions.
A next step would be to phase out the diesel locomotives now used on the line. Electric trains powered by overhead wires are the most common form of zero-emission train, but battery-powered and hydrogen-powered locomotives also exist. There is already overhead wire on the Providence Line, but the T isn’t using it because it doesn’t own any electric locomotives; slashing emissions on the Providence and Fairmount Lines should be a near-term priority.
The Fairmount Line still has relatively low ridership compared with some other commuter rail routes, carrying around 3,000 people a day, and there has been the occasional grumble that scarce MBTA dollars should be going to lines with higher ridership. But that’s the wrong way to view investments in the Fairmount Line. If the T can figure out a way to deliver fast, frequent, and clean service to residents of Dorchester, it will be a big step closer to figuring out a way to do it for the rest of Greater Boston, too.
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