WASHINGTON – A rebellion that began in Old Lyme and has spread along coastal Connecticut is pressing the federal government to make big changes in an ambitious plan to bring high-speed rail to the Northeast, and to turn the proposal into merely “aspirational” recommendations.

“Opposition is growing along the entire shoreline,” said Gregory Stroud, director of special projects for the Connecticut Trust for Historic Preservation, a leader of the opposition.

Connecticut would be the most affected state among the eight involved in the Federal Railroad Administration’s NEC Future, a $135 billion plan to upgrade train service in the nation’s busiest rail corridor.

Demographers project that between 2010 and 2040, the population in the Northeast Corridor will grow to 64 million, an increase of roughly 23 percent. Six of Amtrak’s busiest stations are in the corridor, with New York and Washington, D.C., ranked first and second for passenger traffic.

Besides improving rail lines and adding tracks along parts of Connecticut’s coastline the NEC Future plan incorporates the state’s plan to upgrade the New Haven to Hartford to Springfield line, the only part of the proposal for Connecticut that hasn’t come under attack.

But the wave of opposition to the FRA’s other recommendations may push the agency to scrap many of its ideas, including construction of a bypass that would cut though Eastern Connecticut, including Old Lyme.

“Old Lyme has made its concerns known,” FRA spokesman Marc Willis said.

The FRA is under great pressure as it drafts its final Record of Decision – which could be released as early as late May – to focus instead on what the Malloy administration and many local officials want – to upgrade and fix Connecticut’s existing rail infrastructure.

State officials and residents, as well as a number of state historical societies and environmental groups, have sent hundreds of letters to the Federal Railroad Administration since the beginning of the year to try to influence the agency.

There’s evidence the heavy lobbying may have made an impact and some of the proposed changes – besides the proposed new route between Old Saybrook and the village of Kenyon in Richmond, R.I. – may be eliminated and others downgraded to suggestions.

While eight states are involved in NEC Future, all through the planning process Connecticut was viewed as a “bottleneck,” it’s old, curved tracks, especially those that hugged the coastline, an impediment to upgrading rail transportation in the Northeast.

“To get faster, more reliable service, you have to straighten the rails out north of New York to Boston,” Willis said.

The FRA floated several proposals, but the favored alternative, released in December, was roundly denounced by residents of Old Lyme because the proposed bypass from Old Saybrook to Rhode Island would run through that town.

That touched off concerns that faster rail speeds would come at a cost to the historic character of the southeast corner of the state. The rebellion spread.

There are now worries because the plan to upgrade rail service in Connecticut will bypass New London, Groton and Stonington.

“It would make [New London’s] Union Station obsolete, and that makes no sense to us,” said James Butler, executive director the Southeastern Connecticut Council of Governments. “We would prefer to see the money used to repair and upgrade existing tracks.”

The FRA’s proposal to add tracks to the stretch of the existing corridor from Branford to Guilford also has provoked opposition.

“Double tracking could…lead to the destruction of many homes and communities, endanger historic properties and impose significant harm to homes and communities,” Sen. Richard Blumenthal wrote acting FRA Administrator Patrick Warren on April 12. “It is imperative that these concerns be addressed immediately before the FRA moves towards a Record of Decision, a process I understand is underway. I urge you to engage in thorough discussions and dialogue with the residents of Branford, Guilford and nearby communities in order to ensure these concerns are resolved.”

Meanwhile, in Fairfield County there’s growing pushback on the plan’s proposal to lay down a new two-track line from New Rochelle, N.Y., to Greens Farms in Westport.

Commuter-rich Fairfield County is suffering from traffic congestion and the need for improved rail service, but it’s also worried laying down new tracks would harm property values in its pricey neighborhoods.

Darien First Selectman Jayme Stevenson said there’s anxiety in the town about the proposal’s recommendation that embankments and aerial structures be used to carry the new tracks.

“High-speed rail is a fantastic idea on its face, but when you analyze it community by community, the impact to individual communities can be dramatic and negative,” Stevenson said.

Like other local officials, she thinks the best thing in the FRA plan is its proposal to put the existing railroad network in Connecticut “in a state of good repair.”

The Malloy administration has urged the FRA to release its Record of Decision as soon as possible — and to leave out specific recommendations on laying down new tracks.

James Redecker, commissioner of the Connecticut Department of Transportation, said Connecticut and New Jersey kicked off the process for NEC Future years ago. But he said the goal was to speed improvements along the Northeast Corridor with the federal government’s help.

“We never envisioned the brand-new alignments,” Redecker said. “Our whole purpose was to expedite projects that had to be done.”

He said the NEC Future recommendations have caused “anxiety and opposition” to what is merely the FRA’s recommendation for how the rail bottleneck in Connecticut could be solved.

He wants the Record of Decision to make clear the recommendations are “aspirational and not part of the record.”

He also wants the ROD to move forward certain projects that are important to the state. The Record of Decision would pave the way for the next step in the process, called Tier 2 , which would begin environmental and other studies of individual projects in the eight-state region over the next several decades.

“Each Tier 2 project study will involve engineering, design and environmental review with the involvement of affected communities and the public,” the FRA says. “During the Tier 2 process all necessary approvals and permits from regulatory agencies will be obtained as required.”

Moving into Tier 2 would allow the state to move forward on a new railroad bridge across the Connecticut River and work on the 111-year old Devon Bridge in Stratford, Redecker said.

“What we are trying to do is to focus on an existing corridor without entering into significant projects,” he said.

Those “significant projects” include new tracks, bypasses, aerial structures, embankments and tunnels that were included in NEC Future.

The state has even asked the FRA to drop plans to electrify rails from Hartford to Springfield, Mass., from the ROD because the environmental impact study and other hurdles that project would have to clear would take too much time.

“We wanted to get projects approved that could be built as soon as possible,” he said.

Redecker also said there’s a “high probability” the federal government will consider the state’s position in its Record of Decision, although the FRA was hesitant to provide a timeline for its release.

“The FRA recognizes that many of its stakeholders are eager for the release of the NEC Future Record of Decision,” Willis said. “The NEC Future project team is hard at work completing its analysis with a continued goal to release the ROD in 2017.”

Francis Pickering, executive director of the Western Connecticut Council of Governments, said part of the opposition to NEC Future may be based on the fact its proposals to improve rail service in Connecticut were new and hadn’t been considered by the state officials or the public.

“In other parts of the Northeast Corridor, improved rail speeds had been more extensively studied than in Connecticut,” he said.

There was also a concern Connecticut would not fully benefit from the introduction of high-speed rail because its cities might not be large enough to merit a stop.

“We’re a drive-through state, and we don’t want to be a train-through state,” Pickering said.

Stroud of the Connecticut Trust for Historic Preservation said “there is absolutely a concern” that high speed trains would whiz through the state without stopping.

“Connecticut is different than New York or Massachusetts in that we lack a very large city,” he said.