Concrete is curing on the Sewalls Falls Bridge after a milestone in construction Thursday, when its deck began to take shape.
Beginning at 6:15 a.m., a towering concrete pumper stationed at the eastern foot of the bridge began to churn liquid concrete through its 62-meter arm to the work zone over the Merrimack River.
“This is a big step in the job,” said Mike Cole, vice president of Concord contractor E.D. Swett, which was awarded the job last year. “Once the bridge deck is on, everything else falls into place rather quickly.”
Cole said all of the concrete should be cured by Oct. 12, at which point crews will begin to pave all 2,800 feet along Sewalls Falls Road between Manor Road and Interstate 93.
The 400-foot-long bridge should be open to traffic by early November, which Cole said is the project’s “intermediate completion date.” The final completion date – when all the cosmetic work and walkways will be finished – will be at the end of June, he said.
On Thursday, one of the 50 construction workers used a remote to control a massive arm dumping concrete, while others waited at the end of the boom to smooth and prepare the material as it poured out in globs.
A Bid-Well concrete deck finisher churned the concrete once more with an auger. At the rear of the machine, it smoothed the concrete into its final form, crowning ever so slightly at the center of the road in accordance with the engineers’ design.
In this way, the crews placed about 330 cubic yards of concrete Thursday onto the deck of the $10 million bridge.
The concrete was poured onto a base of precast concrete panels and reinforcing steel bars.
“In layman’s terms, we’re putting on the travel way for automobiles,” Cole said. “Add 2.5 inches of asphalt, and it’s going to take traffic.”
The November completion for traffic is much anticipated for Concord drivers traveling between Fisherville Road and Mountain Road. For nearly two years since the historic former bridge was dismantled, they’ve had to find another crossing, adding several miles to the trip.
“We’ve been working six days a week since we were awarded the contract last September,” Cole said. “That’s right through the winter.”
(Nick Reid can be reached at 369-3325, nreid@cmonitor.com or on Twitter at @NickBReid.)