In 1911, the Massachusetts Bay Transit Authority built the Annisquam River drawbridge for commuter trains, and crews reconstructed it in 1932.
Flames licked the wooden bridge in 1984, necessitating an update for the structure. Fast-forwarding to 2010, the bridge was declared in the worst shape of any in the MBTA's commuter rail system.
So in 2013, the century-old, wooden bridge, an oft-painted view, will be replaced with a modernized concrete-pillared drawbridge.
The new drawbridge has an expected lifespan of 75 years, according to Massachusetts Bay Transit Authority (MBTA) spokesman Joe Pesaturo. Transportation officials have been sure to note that the bridge's new trestle, the support frame, will consist of fire-resistant material: concrete.
At a public forum here Thursday night, state transportation officials met with Senate Minority Leader Bruce Tarr and the public to present bridge designs by Boston-based Fay, Spofford & Thorndike, which are about 60 percent complete. Tarr had requested the public meeting in order to share plans for the sorely-needed replacement bridge with the public.
"I'm impressed by the design," Tarr said. "I think it will be reliable and long-lasting."
In bridge plans, inspired by a South Australian drawbridge and the Woodrow Wilson Bridge in Washington, D.C., engineers opted for concrete and avoided timber, which can be more susceptible to the elements, according to Pesaturo.
In a summary of project benefits, MBTA officials wrote: "The existing bridge, which has served the community well, is reaching the end of its useful design life ... The replacement bridge will provide decades of reliable service."
Though few pieces of the century-old bridge are salvageable, the abutments on either side of the bridge will be cleaned, repaired and reinforced to allow for continued use on the new drawbridge during construction.
Two sets of gray pillars and a massive concrete block surrounding the bridge's draw mechanism will replace scattered bundles of wooden beams beneath the bridge, while a tidy railing will line boats' travel path between the pillars, according to the plans.