The Board of Aldermen Thursday further considered funding for the Green Line Extension (GLX).

As the Dec. 8 deadline approaches, some Aldermen mentioned that they are inclined to approve Mayor Joseph Curtatone’s request to contribute $50 million.

After the long-promised GLX was revealed to be more than $1 billion over budget last year, the state revised the project to a bare-bones level. In an unprecedented request, the state asked Somerville and Cambridge to contribute $50 million and $25 million, respectively, to fill a gap in the budget. The Federal Transportation Authority (FTA) plans to contribute $1 billion to the project, pending the results of an ongoing risk assessment.

At the meeting, multiple Aldermen said that Somerville residents are nervous about rising taxes. With the price of the project, combined with the $256 million high school, people are worried about Somerville’s affordability.

“When does this first hit, in a major way, the taxpayer?” asked Alderman President Bill White. “When will the principle interests of this show up on the tax bill?”

Somerville Director of Finance Auditor Ed Bean explained that if the state Legislature passes the city’s home rule petition, costs associated with the GLX will likely hit taxpayers in six years. If the Legislature does not approve the petition, residents could feel an impact as soon as 2020.

The Somerville High School debt exclusion will hit tax bills in small amounts starting in 2018, rising gradually to an estimated peak of $300 for single-family homeowners until it is paid off by 2054.

“I think it’s important that we let (taxpayers) know that we’re trying to stagger it as long as possible in the future,” said White, who suggested city budgets will be lean in coming years to alleviate some of the debt burden.

Alderman Mary Jo Rossetti asked whether the city could allocate $2 million from the recent Powderhouse School sale toward the GLX bond, potentially decreasing the principle to $48 million, to help alleviate the burden. However, city officials advised that the money legally needs to be put into debt service, but promised to look into ways to apply it towards the GLX.

White asked Curtatone to confirm that state officials will not ask Somerville for more money down the line if the project were to go over budget again.

“I’ll tell you what I told them: we’ve given you what we can,” Curtatone responded. “We want the Green Line, you owe us the Green Line, you need to build the Green Line. But we can only put up what we can pay for. We were pretty clear with them.”

If the project is completed and comes in under budget, Somerville and Cambridge will receive state reimbursements proportional to their respective contributions. If, for some reason, both cities make their contributions and the GLX is not built, the municipalities will be fully reimbursed by the state.

Though an expensive project, head of transportation Brad Rawson said that the GLX will bring "incredible benefits" to Somerville. According to recent projections, he said, an estimated 49,000 people will ride the Green Line on opening day.

The GLX will create social equity among residents, he continued, providing everyone with equal access to public transportation. And, he added, it will reduce Somerville’s carbon footprint.

Rawson noted studies showing the average Somerville household could save $10,000 if they can go from a two-car family to a one-car family, or from a one-car family to a zero-car family, a decision closely tied to the availability of alternate transportation options like the GLX.

However, some residents feel that the GLX may not be accessible to everyone.

At a November community hearing, residents were outraged that the community path will end at Washington Street under the new pared-down GLX design, rather than extending to Boston as originally planned.

Friends of the Community Paths (FCP), a local advocacy group fighting to extend the associated community path to the Charles River pathway, will meet with state officials on Dec. 5.

Lynn Weissman of FCP said that the meeting will include GLX supervisor John Dalton, city officials, the Conservation Law Commission, and the Somerville Transportation Equity Partnership. Weissman’s team plans to present a cost-saving design that will effectively connect the Minuteman Path to the Charles River.

The FCP wants the community path extension be a top priority in alternative technical conceptions submitted by GLX builders in the coming months, Weissman said. But in the meantime, she said that she still supports the GLX.

“The benefits of this project outweigh the downside,” she said.

The Board of Aldermen will meet at 7 p.m. this Tuesday, Dec. 6, to discuss the GLX plans further.