The southbound side of the Gold Star Memorial Bridge was a hub of activity on Wednesday morning, like most days.

Wearing yellow safety vests, hard hats and face shields, a crew of construction workers used jackhammers to break up deteriorated concrete on the bridge's pedestrian walkway and soon after vacuumed the pieces into a truck.

On another section of the bridge between New London and Groton over the Thames River, a crew smoothed over a fresh patch of fast-setting concrete. The crew then will have to add brush strokes with a broom, so the surface won't be slippery for pedestrians and cyclists once the sidewalk repair project is finished.

Workers in buckets of long-armed snooper trucks also installed brackets underneath the bridge to hold debris shields in place, so workers could later begin demolishing the concrete sidewalk in those areas.

“It’s a constant orchestra of moving materials, moving manpower,” Keith Schoppe, project manager with the state Department of Transportation, said as a fork lift dropped off a pile of brackets in the work zone.

Multiple construction crews from Mohawk Northeast, aided by machinery and vehicles from excavators with small concrete buckets to concrete mixers, have worked during the day, and at night when possible, to repair the more than mile-long sidewalk on Connecticut's longest bridge. They are making the repairs along the length of the bridge in a work zone that is sealed off from the zooming vehicle traffic by concrete barriers.

The sidewalk repairs are one of the final remaining components of a project to rehabilitate the Gold Star Bridge's southbound Interstate 95 structure, which was built in the 1970s and last had major work completed in the 1990s. The project, which is being inspected by DOT along with FIGG Bridge Group, began in April 2017 and is scheduled to wrap up in the late fall, according to DOT.

Crews already have stripped off the old membrane on the bridge deck and patched up areas of concrete, installed a new membrane and paved the deck, replaced joints, repaired steel, patched up areas on the concrete substructure, replaced lamp posts and installed new sign structures, Schoppe said. 

For the sidewalk repairs, Schoppe said DOT initially anticipated that it only had to replace a few patches of concrete "here and there."

"We would have just closed the sidewalk for a week and would have worked around the clock," he said.

But inspections revealed that about 25 percent of the sidewalk needed to be replaced, which required a longer closure. The sidewalk repairs began on Aug. 13 and are expected to be finished on Nov. 1.

After inspecting the sidewalk, workers marked the sections needing full-depth repairs. A few spans in the middle of the bridge required almost complete replacement of the sidewalk, while other spans only had a few areas in need of patching up, he said. The work also includes fixing and realigning the rebar under the concrete, as necessary, and replacing joints.

Schoppe explained that replacing the entire sidewalk would have been beyond the scope of the project and the cost "astronomical," so the DOT is focusing only on the areas in need.

During the repairs, DOT removed about 4,000 feet of fencing and installed temporary fencing, Schoppe said. The workers are fixing the parts of the fence that are in need of repair or replacement and will reinstall the permanent fence after the concrete repairs. DOT also plans to push out the fencing a little bit in areas where the foundations of sign structures have obstructed the walkway.

The last step will be to seal the entire walkway to protect it from salt and water penetration, Schoppe said.

During the sidewalk construction project, DOT is paying Southeast Area Transit District to operate a daily shuttle to pick up passengers at the entrances of the walkway in New London and Groton that are closed during the repairs. The shuttle, which is free for riders, runs from 6 a.m. to 6 p.m. on the weekdays. Starting this weekend, the bus will run from 8 a.m. to 4 p.m. on Saturdays and Sundays, rather than from 6 a.m. to 6 p.m. as before, due to low ridership, SEAT and DOT announced this week.

Schoppe said Mohawk Northeast, the contractor, has done a "phenomenal job" and understood when the DOT said the sidewalk repairs need to completed in a short window of time. He also praised SEAT for being very cooperative and helpful.

The final steps in the overall bridge project include completing steel repairs on the left side of the southbound structure; line striping the new deck pavement; and removing the old sign structures and placing signs on the new structures, Schoppe said.

While the bridge rehabilitation project initially was estimated at about $26 million, Schoppe said it's currently estimated at $35 million due to the more extensive work that was determined to be needed after inspecting the bridge, including replacing expansion joints and repairing steel. The more extensive sidewalk repairs had added about $2 million to the total project. 

But Schoppe said it's money well spent to ensure the bridge stays in good shape for the next 25 years.

"The idea is we don't want to come back here anytime soon," he said.

After work on the southbound structure wraps up, the northbound structure is in line for an upgrade. The DOT said it plans to go out to bid for that project in 2019.

k.drelich@theday.com