Land around T and commuter-rail stations in the Boston area could support at least 253,000 new housing units, report says

The areas immediately around T and commuter-rail stations could support an estimated 253,000 new housing units, according to a new report from the Massachusetts Housing Partnership’s Center for Housing Data.

And that’s just a ballpark. The land, especially around commuter-rail stops, could support a lot more transit-oriented development, the sort that would not only provide the Boston region much needed housing but reduce its notoriously vehicular traffic congestion.

The center developed a methodology to map the housing density that all 261 T and commuter-rail stations could support within about a half-mile.

Right now, overall density near the stations averages about 6.5 homes per gross acre. The Massachusetts Housing Partnership, an affordable housing group, is advocating raising that to an average of about 10 homes per acre—a relatively modest density more akin to suburbia than urban streetscapes.

In fact, the partnership says the 10-homes-per-acre density could be achieved not through large new apartment buildings but through a mix of single-, two-, and three-family homes.

“While this math is incredibly simple and ignores some important neighborhood factors, it does show the potential that reimagining these high-access neighborhoods could have in terms of better supporting transit while simultaneously making a huge dent in our chronic housing supply problem,” the Center for Housing Data said in a summary of the report (which includes a handy tool for analyzing the density around the 261 stations).

As the center noted, though, there are myriad factors affecting the potential for such transit-oriented development. Each city and town in the Boston region has its own zoning regs and hurdles re: housing—note what’s been going on in Newton as far as building along the Green Line.

Also, history is not on the housing partnership’s side. Of the 261 stations, 162 average fewer than 10 homes an acre—and 119 of these, most of them commuter-rail stations, average fewer than five homes an acre.

Then, of course, is the mass transit itself. The T and commuter rail both struggle with current ridership. Adding that many more riders through new housing near stations would only add to the burden.

But, as the Massachusetts Housing Partnership’s report points out too, there is already heavy ridership around stations that don’t have a lot of housing density relative to other stops. See the map below of the average density along the Red Line. Ridership is heavy along the line’s Braintree branch even though density is smaller. That’s likely due to riders coming in from farther away to take the T, the report said.

Meanwhile, vehicular traffic is expected to worsen in the coming years and the backlog for repairs to the T, never mind improvements, runs into the billions of dollars. And the region’s population could crest 5 million any year now.