THE LEGISLATURE’S TRANSPORTATION COMMITTEE heard testimony Wednesday on a bill that could help fund the cash-strapped Green Line Extension, but neither the communities that would provide the funding nor the MBTA which would spend the money showed up to say whether they supported the legislation.

The bill, filed by the House chairman of the committee, Rep. William Straus of Mattapoisett, would allow the state to use property tax revenues collected on growth resulting from a transportation investment to pay off bonds used to finance the project. Straus said the approach could be used to help finance the Green Line Extension, South Coast Rail, and other transportation projects around the state, including highway off-ramps that spur new development.

Officials from the MBTA and officials from the three communities through which the Green Line Extension would travel have indicated in the past that they are interested in the so-called value capture financing approach, but none of them testified at the State House Wednesday.

Jacqueline Goddard, a spokesman for the state Transportation Department, said a representative from the agency was at the hearing but did not speak or offer written testimony.

Mayor Joseph Curtatone of Somerville said in a telephone interview that he was grateful to Straus for filing the bill but could not attend the hearing because he had another engagement. As for value capture itself, he said he and his aides are working with state officials trying to figure out what would work best.

“The concept of value capture, we’re all trying to understand what it is and what role it will play,” he said.

At the conclusion of the Transportation Committee’s three-hour hearing on a wide range of legislation, the Senate chairman, Sen. Thomas McGee, was asked what he made of the fact that none of the affected parties showed up to testify on the value capture bill. “That is a good question,” he said. “I really don’t know.”

Straus, who was away taking a vote in the House when the hearing concluded, said later via email that he wouldn’t read too much into the absence of the T and officials from Somerville, Medford, and Cambridge. “The process of input, frankly, is always more than the hearing,” he said.

Thomas Ryan, manager of public policy and government affairs for A Better City, which advocates on transportation issues, said value capture requires more study. He noted a Value Capture Commission is studying the issue and has more work to do. Ryan’s boss, Rick Dimino, the CEO of A Better City, sits on the commission.

While Ryan was not opposed to value capture, he said it needs to be introduced carefully because it could place a heavy burden on some developers and communities. He also suggested value capture should not just seek to capture growth in property tax revenues but also growth in sales and income taxes in the area around a transportation investment.

One of the chief criticisms of value capture is that it would not raise enough revenue to have a significant impact on the financing of a project of the magnitude of the Green Line Extension. T officials had planned to spend $2 billion on the project, with $1 billion from the federal government and $1 billion from the state. Last year, the estimated cost of the project ballooned to $3 billion, and state officials are now trying to figure out ways to cut costs and raise revenues to make the project feasible.

Nicholas Downing, a government affairs specialist for the Metropolitan Area Planning Council, testified that value capture has a role to play in the state’s overall transportation discussion. “It’s something we know we need going forward,” he said.