Connecticut moved $120.9 million closer on Monday to a high-speed rail line running between New Haven to Hartford, and Springfield, Mass.

The $121 million grant will help fund the $880 million project to create a commuter railroad along the north-south corridor from lower Connecticut to central Massachusetts, U.S. Sen. Christopher Dodd, Gov. Jodi Rell and other state officials, at a news conference from the Meriden Train Station.

State and city officials said the new rail will reduce highway traffic and promote job growth in New Haven. The new line will have double-rail tracks that allow for speeds of up to 110 miles per hour and more frequent departures, but a $379 million funding gap still remains.

Stops on the 54.3 miles of track to be built in Connecticut will include Wallingford, Windsor and Hartford with a link to Bradley International Airport. Average train speeds are expected to rise from 40 mph to around 60 mph.

Although a commuter rail already exists between New Haven and Springfield, currently operated by Amtrak, the National Railroad Passenger Corporation National Railroad Passenger Corporation, service is limited by the constraints of a single-track railroad, said Michael Piscitelli, director of the New Haven Department of Transportation.

The core of the proposal is to create a double-track line from the original single-tack rail and improve the stations, he said.

“By double-tracking the line and improving the safety, you can improve the schedule, the frequency of the service and thereby generate ridership,” Piscitelli added.

The state originally requested $220 million from the Federal Railroad Administration for the new rail line in 2005, but only received $121 million. Monday’s announcement brings the total funding for the project up to $421 million, after the state Bond Commission announced in August it would provide $260 million in funding and the project received $40 million in federal stimulus dollars specifically for creating double-track between New Britain and Newington.

Local and state transportation officials hope that the new line will clear traffic along state highways, particularly I-91, by around 4,000 cars a day, according to a press release from the state Department of Transportation. The reduction in traffic will save one billion gallons of fossil fuels annually, the release stated.

The line will be particularly efficient for residents commuting to Hartford, Ward 7 alderwoman Frances “Bitsie” Clark said.

“It’s going to be commuter-oriented,” she said. “People are going to be able to live in New Haven and work in Hartford and not have to drive on 91.”

University officials, too, expressed enthusiasm over the announcement. In an e-mail to the News, Vice President for New Haven and State Affairs and Campus Development Bruce Alexander said the project will be an economic boon to the city. The rail line from New Haven to Boston along the shoreline currently runs at full capacity, and because it’s built near wetlands, it is unlikely to be expanded, Alexander said. Adding an inland route from New Haven to the Boston area will “enhance the economic prosperity of New Haven and Connecticut,” he added.

The construction project will also promote future job growth in the New Haven area. Short-term, the project will bring construction jobs, as well as peripheral jobs for those who supply clothing and tools for construction workers, Ward 6 alderwoman Dolores Colon said. After the line is completed, the improved flow of traffic will make the downtown business district more accessible for drivers and pedestrians.

“Investments in transportation infrastructure promote density, and density is a friend to cities because it promotes job growth,” Mayor John DeStefano Jr. said in a Tuesday interview.

Piscitelli said he hopes the new rail line will help New Haven grow as the center of Connecticut’s transit system, making New Haven a final destination for commuters, not just a connecting stop.

The proposal for the New Haven-Springfield line emerged in 2002 from regional discussions about the construction of the State Street train station, according to Piscitelli. These discussions prompted additional conversation about streamlining train service between New Haven, Hartford and Springfield, he added.

Four students from the Hartford and Springfield areas interviewed said they would take advantage of the new high-speed train.

Thu Do ’13, of Amherst, Mass., said the current lack of transportation options is frustrating, and would “definitely” choose the train to Springfield.

“[The new train] would be 10 times easier,” she said.

The state Department of Transportation projects that the line will not be up and running until late 2015.