State Rep. Evandro Carvalho said this week that he would support Mayor Walsh’s new plan for a pilot project to enhance service on the Fairmount commuter rail line.

Earlier this year, Carvalho proposed a bill that was shaped with advocates who want a rebranding of the Fairmount Line: A two-year pilot that would run trains every 15 minutes at peak hours, and 30 minutes at off-peak hours. This would align with the advocates’ stated goal of making the Fairmount Line, the only commuter rail route to operate entirely within Boston, more akin to a rapid transit line.

The Walsh proposal seems to operate within the constraints of a typical MBTA pilot, with an 11-month testing period ideally using trains already available on the line.

Details on the mayor’s pilot remain slim, although sources within the Walsh administration said the pilot would aim to boost ridership on the line by increasing frequency. Trains along the 9.2-mile Fairmount stretch currently run every 40 minutes or so, which residents have long said leaves riders along the line without reliable rapid transit options.

“I want to thank Mayor Walsh for helping promote the Fairmount Line and its value to our community,” Carvalho said on Tuesday. “Rapid transit service on the line would be a tremendous benefit to those living in the corridor, and I am happy to support the mayor’s efforts to do exactly that.”

An MBTA panel recently approved a proposal to extend daily service on the Franklin and Fairmount lines to Foxborough. Last Friday, the Lawyers’ Committee for Civil Rights and Economic Justice, the Greater Four Corners Action Coalition, and the Fairmount Indigo Coalition submitted a public records request to the MBTA for the immediate disclosure of information concerning the proposed extension.

They are also seeking demographic data on transit users and “information concerning the racial and economic impact of the Fairmount Line service modification.”

Wrote the group in a press release: “Low-income transit-dependent residents rely heavily on the Fairmount Line. The proposed Foxborough extension may result in express suburban commuter trains that skip urban stations used primarily by minority and immigrant passengers. In this manner, the Foxborough extension may dilute the quality of transit service available to passengers of color.”