By George P. Hassett

Gov. Deval Patrick’s proposal to delay the extension of the Green Line through Somerville and into Medford by two years has sparked outrage throughout the city.

State Rep. Denise Provost, D-Somerville, said she was “appalled,” and Board of Aldermen President Robert C. Trane said he was “extremely disappointed” by Patrick’s plan to delay the completion date of the project from 2014 to 2016 to seek federal funding to pay for half of the $608 million project.

In 1990, state officials promised Somerville residents they would complete a Green Line extension through the city as a way to offset air pollution in the city caused by the Big Dig. In 2005, the Conservation Law Foundation (CLF) sued the state because it had not taken the necessary steps to complete the project on time. In November 2006, CLF and the state settled and agreed on a binding commitment to complete the project by 2011. That commitment was pushed back to 2014, and now attorneys for CLF say the state is, once again, trying to go back on its legal obligation.

Carrie Russell, staff attorney for CLF, said if Patrick’s proposal to delay the project becomes a reality, the organization will resume its lawsuit. If CLF are forced into a courtroom battle, it will have plenty of support from city leaders. Mayor Joseph A. Curtatone said the city would support CLF in a lawsuit against the state.

“We fully intend to push back hard and hold the state’s feet to the fire on their legal commitment,” he said.

The Board of Aldermen unanimously passed a resolution Aug. 9 supporting the Green Line extension into Somerville. Curtatone said he has not spoken with any citizens, officials or business owners in the city who oppose the project.       

Becky Deusser, a spokeswoman for Patrick, said the administration is committed to completing the project but wants to do it in the most fiscally responsible way possible.

“Getting federal funding for the project would save half of the project cost, which amounts to $300 million in savings for taxpayers,” she said.

In March, a study conducted by the Transportation Finance Commission said the state’s public transit system faces a $20 billion shortfall over the next 20 years and planned projects such as the Green Line extension cannot be completed because of money woes.

Curtatone said he supports the idea of seeking federal money for the project but maintains it does not have to be delayed as a result.

Provost said previous Gov. Mitt Romney’s administration had also planned to seek federal money for the project but never believed that would mean a delay.

Deusser said the current administration would work with federal officials to streamline the process and save time. But local activists said they have already waited too long.

“We’re incredibly disappointed, it feels like Somerville is being jerked around again,” said Ellin Reisner, president of Somerville Transportation Equity Partnership (STEP), an equity transit group that has worked on the Green Line project since 2003. “There is no guarantee we can even get federal funding. 2016 would be the earliest it could it could happen. We expect it would be even later than that.”

The delays in the Green Line extension symbolize the neglect of urban mass transit systems in the last 20 years, Provost said. She said previous Republican administrations in the state have devoted more money to suburban commuter rails while pushing aside the transportation needs of city dwellers.

That was all supposed to change when Patrick, with early and strong support from Somerville, was elected governor. Patrick was endorsed by Curtatone, all five state delegates, the entire School Committee and nine of the city’s 11 alderman. One reason for his broad support in the city was the feeling that his administration would invest in urban transit systems, Provost said.

“Somerville came out big for the governor,” Trane said. “Now to see him push back the Green Line once again is extremely disappointing.”

Reisner said Patrick has underestimated how significant the project is in Somerville and the astounding level of community support for it.

“He believes Somerville is in his pocket, but we voted for him thinking he would follow through on the legal commitment to complete this project by 2014,” said Reisner.

She said the project calls for up to four new Green Line stops in the city with possible locations in Gilman Square, Ball Square, Union Square and on Lowell and Washington streets.

Benefits for the city include improved public transit, better air quality as commuters shift from automobiles to riding the train and expanded commercial development potential in East Somerville and Union Square, Curtatone said.

Two hearings will be held in Boston at 1 Winter St. on Sept. 6 at 1 p.m. and 5 p.m. to discuss the extension.

Alderman-at-Large William A. White said for now the city’s best option is for residents to show up at the meetings and be heard.

“Everybody should show up and make it clear that as a city we are unified on this issue,” he said.

Provost said the state delegation will meet with Patrick Aug. 21 to further discuss his plans for the Green Line extension.