Less than 100 yards from this crush of commuters, the Northern Avenue Bridge sat empty and rusting, as it has for nearly five years since being closed for safety reasons.

Meanwhile, the Moakley’s sidewalks were thick with pedestrians, many lugging backpacks on the way home from work, while cyclists pedaled along a narrow, unprotected bike lane.

A little before 5 p.m. one recent day, cars and shuttle buses stacked up on the Moakley Bridge across Fort Point Channel and for blocks down Seaport Boulevard. It’s a daily traffic nightmare that has become as much a part of the booming Seaport neighborhood as glass-paneled condos and shimmering waterfront views.


Now, as the city considers how best to rebuild the 283-foot span, there’s a roiling debate about what mix of cars, shuttles, bikes, and pedestrians it should carry.

A view of the Northern Avenue Bridge from the Seaport side. Lane Turner/Globe Staff/Globe Staff

Some people, including Mayor Martin J. Walsh, see those stacked-up cars on the Moakley Bridge and say every vehicle lane matters in tackling the Seaport’s traffic. They want a new Northern Avenue Bridge that’s designed largely for cars, or at least shuttle buses.

Neighbors and vocal cycling advocates envision a bridge that accommodates bicyclists and pedestrians foremost, as it did for 20 years prior to being closed in 2014.

In context, the modest Northern Avenue Bridge is not a critical link in the city’s transportation system. At most, a new one would add two lanes of traffic, a relief valve for a corner of the Seaport.

A close view of the Northern Avenue Bridge. Lane Turner/Globe Staff/Globe Staff

But the discussion over its redesign is shaping up as a sort of Rorschach test for the traffic snarl vexing the Seaport, and Boston as a whole. Should moving cars be the priority? Or is putting cars first precisely the problem? Can shuttle buses safely mix with people on foot? And at what cost?

City engineers will soon weigh in on those questions and more. They’ve scheduled a public meeting on Monday to present a range of designs — from a $40 million 12-foot-wide span solely for walkers and bikers to a $150 million major redo with 64 feet of lanes for motorized vehicles, cyclists, and even shops. They aim to pick one later this summer, and to start work by 2021.


Like any project, it’s a balancing act between competing priorities, said Chris Osgood, Walsh’s transportation chief. The city has to consider history, mobility, climate resilience, and the desire to create an interesting piece of architecture on the waterfront.

“We’re trying to find the right mix,” Osgood said. “It’s been a good conversation.”

A pedestrian crossed the Evelyn Moakley Bridge on Seaport Boulevard, seen through the rusting girders of the Northern Avenue Bridge. Lane Turner/Globe Staff/Globe Staff

For months, that conversation has played out on a task force advising Walsh on the new bridge. Seaport business groups and developers are pushing for something that could, at least, accommodate corporate shuttles and other high-occupancy vehicles, citing studies by city consultants that suggest crossing the Northern Avenue Bridge instead of the Moakley could shave four minutes off a shuttle ride to North Station. They argue that it also could provide backup capacity for cars if one of the other bridges closed.

Source: OpenStreetMap, NextZen Saurabh Datar/Globe Staff

Advocates for cyclists and pedestrians have said that such a time gain is minimal, and the city shouldn’t overdesign for vague, worst-case scenarios. They point to those same city studies that predict as many as 2,800 people an hour would cross the Northern Avenue Bridge on bike and by foot when the Seaport is fully developed.


Then there’s the nearby Moakley Courthouse, where officials stress the need for emergency vehicle access in case of an incident. And don’t forget the neighborhood groups that would like to see the bridge return to what it was in its car-free final years, a haven in the bustling city.

“It was a great place to be, a fun place to be, and a comfortable place to be,” said Greg Galer, executive director of the Boston Preservation Alliance. “If we’re going to lose this historic bridge we should at least try to capture the essence of it.”

Critics of any plan that prioritizes cars say it won’t do much to alleviate traffic. While the Moakley feeds directly into busy Interstate 93 North, the Northern Avenue crosses Fort Point Channel a bit to the north, and would funnel cars into an already-congested stretch of Atlantic Avenue.

But even minor improvements are worth it, said Yanni Tsipis, senior vice president at WS Development, which is building the massive Seaport Square complex. That 23-acre project includes bike lanes and better sidewalks and a new entrance to the MBTA’s Silver Line. But WS, like its neighbor Fallon Co., which developed Fan Pier, says a bridge that carries shuttle buses should be part of the solution, too.

“There’s no one silver bullet,” said Tsipis, whose company agreed, during city permitting, to contribute $2 million for the Northern Avenue Bridge. “The solution comes from lots of small incremental things, and having [shuttles on the Northern Avenue Bridge] is one of those.”


While city engineers say they’ve yet to make a final decision on what the bridge should carry, their boss appears to be siding with those who are pushing for vehicles. Walsh recently said building a bike-and-pedestrian bridge doesn’t make sense.

“I don’t think we can,” he said. “I mean, in a perfect world, absolutely. But one of the biggest concerns people have is getting off the waterfront at 5 o’clock. That’s one of the biggest complaints I hear.”

The Northern Avenue Bridge, Walsh said, needs to carry vehicles.

“Maybe shuttles and buses,” he said. “Maybe cars.”

That’s a short-sighted approach, said City Councilor Michelle Wu, an advocate for cycling and mass transit, and it contradicts a growing belief that Boston’s traffic troubles will be better addressed by having fewer cars on the road, not more.

“It’s frustrating,” Wu said. “We’re stuck in this mindset that we have to find ways to accommodate vehicles. We should be thinking long-term, about how people can have options other than vehicles.”

That car-first mindset, some observers say, is what led to the Moakley in the first place, a functional slab of concrete that no one appears to love. For the historic and charming Northern Avenue Bridge, longtime Fort Point advocate Steve Hollinger said, the city should strive for something better — or maybe just not bother.

“This is Boston. We don’t do mediocre bridges,” Hollinger said. “We did one, in the Moakley. If this process is just leading us toward another Moakley, why are we building a bridge at all?”


Tim Logan can be reached at tim.logan@globe.com. Follow him on Twitter at @bytimlogan.