Could a new road ease South Boston traffic?

Barry Chin/Globe Staff

The South Boston Bypass Road has long tempted drivers with a way around traffic snarls that bedevil waterfront commuters, a mile-plus-long ribbon of asphalt that holds the promise of freedom.

The connection between the waterfront and the Southeast Expressway is open now to only commercial vehicles — tractor-trailers, cabs, and the like — to keep them out of residential neighborhoods. But as more employers move into the area, bringing with them more congestion, there are hints state officials are preparing for more widespread use of the bypass.

One obvious clue: plans for a project to overhaul Cypher Street and extend it another block, from D Street to E Street. Now a ragged stretch with no sidewalks, Cypher offers an alternative connection between the South Boston neighborhood and the bypass road behind the Boston Convention & Exhibition Center. It can also act as a crucial link between the A Street and D Street corridors, improving the traffic flow to and from the area.

City officials say the Cypher project could include renovations to the existing street, to make it more pedestrian-friendly and to clean up pollutants buried in the soil there, as well as a short extension of E Street to better connect it with Summer Street and the Haul Road.

The full cost has yet to be determined, although two state lawmakers issued a statement boasting that they expect at least $9.7 million to be spent on the project as part of $25 million authorized for road improvements in the area over five years.

The Boston Transportation Department is working with the Massachusetts Convention Center Authority, the Massachusetts Port Authority, and the state Department of Transportation to develop the project, with a goal of securing funding within the next few years.

“That link, although a short distance, is very important,” said Richard Dimino, chief executive of A Better City, a business group involved with transportation planning in the area. “It has to serve many functions.”

State transportation officials declined to say much about either project — the Cypher extension or lifting the bypass restrictions. A spokeswoman said both concepts are under review and no final decision has been made.

Proponents contend the projects could be part of a broader effort to ease congestion throughout the district. In particular, Dimino said the Cypher extension could help keep trucks off that part of D Street, a once-desolate stretch that is now home to hotels, apartments, shops, and a popular park. And he said improving Cypher could also enhance the access to the bypass road, something that would become more important once commuters are allowed there.

State transportation officials hosted a six-month test run that ended in February to study the possible conflicts the commuters could pose to the commercial drivers who rely on the road. The state agency saw no significant impact on the truckers using the bypass.

The pilot project only opened the bypass to inbound commuters during certain morning hours, although a short stretch between Cypher and the Massachusetts Turnpike ramps was fully opened in both ways. If the state transportation department moves ahead, it likely will start with that scaled-back use before opening the entire bypass road at all times.

State environmental officials need to approve any permanent changes to the bypass road’s use.

Massport wants to protect the truckers who travel to and from the Conley shipping terminal and the nearby industrial park; convention center officials are eager to see the area behind their facility become more amenable to walkers and cyclists.

For many residents, simply addressing the existing conditions on Cypher represents a big improvement because there’s no other quick way to get between A and D streets.

“It really looks like a war zone,” said Drew Volpe, a Fort Point resident. “I bike all over the city. I won’t bike over that. The potholes are huge. The streetlights are pretty bad. It’s pretty dangerous.”

Neil Fitzpatrick, president of Boston Freight Terminals, said he would prefer to see the Cypher Street extension limited to trucks only. He said putting too much traffic on Cypher and the bypass road could prompt truckers to travel through residential stretches to get to and from the waterfront. He noted that could conflict with the original goal of the bypass road, built during the Big Dig as a mitigation measure to keep trucks away from homes in South Boston.

But state Representative Nick Collins said the state’s test shows that both constituencies can coexist.

“I think there’s a way for both commuters and trucks to use that road effectively and not get in each other’s way,” the South Boston Democrat said. Collins and state Senator Linda Dorcena Forry recently issued a joint press release that touted funding for the Cypher project.

That said, it could be years before the bypass road is fully opened for outbound commuters because the out-of-town route can get much more congested than the inbound route. Outbound drivers often get stuck in bottlenecks further south, amid the tangle of ramps near the South Bay shopping center, where the bypass connects with the Southeast Expressway.

Cheryl Tougias, an architect from Milton who works on A Street, would prefer to see the bypass road fully opened, alongside an improved Cypher Street. But she said she would be happy to at least be able to use the bypass road in the mornings. She routinely drove on the bypass road during the test run and found that the new route shaved at least 10 minutes off her morning commute, in part by enabling her to miss much of the congestion on A Street.

“A Street has become very challenging with so few ways in and out of Fort Point and the Seaport,” she said. “I think opening it up would really help.”