TOWNSEND -- Aaron Silvestri often makes the short walk from his computer shop in Townsend center down to the Squannacook River, where he eats his lunch on the quiet riverbank.
From his grassy perch on the eastern slope of the waterway, he watches the ducks beg for a piece of sandwich before they float south under the Main Street bridge.
That bridge concerns Silvestri. It carries serves hundred cars per day. With its rusted frame and craggy concrete, it's slowly crumbling.
As bad as the bridge looks, it is not among the state's priority projects, but three other bridges in Townsend are, including the Locke Brook bridge on West Meadow Road. Preliminary surveying is underway at Locke Brook, with construction soon to follow.
The state Department of Transportation has identified more than 400 bridges across the state in need of repair or replacement, including dozens in the Nashoba and Merrimack valley.
Massachusetts ranks 21st in terms of percentage of bridges deemed "deficient," according to a 2017 American Road Transportation Builders Report, slipping from 27th in 2013.
Several streams of funding are converging to address the problem.
Two programs whose source can be traced directly to the state level are MassWorks, and the Municipal Small Bridge Program (MSBP), for structures not eligible for federal funding.
On Monday, Shirley's Main Street Bridge was dedicated by Lt. Gov. Karyn Polito.
Along with DoT money, money from MassWorks and MSBP is being used on the local level for smaller structures and repairs for towns with fewer than 7,000 people. Larger towns are also eligible but with caveats, according to the MassWorks guidelines.
Repairs fall to one of two bodies -- the municipality where the bridge is located, or the DoT -- to address the structural and safety concerns that the National Bridge Inspector's report outlines.
Townsend's Canal Street highway bridge was built in 1850, and each of the 6,000 cars that cross it every day add to the wear. This is a municipally-owned structure, so the town is tasked with the responsibility to upgrade according DoT standards.
The Locke Brook bridge, built in 1917, is also the property of the town.
A third bridge in Townsend, Pearl Hill Brook, built in 1907 and serves more than 5,000 cars per day, falls under the state's purview.
Shirley's Mulpus Brook Bridge, built in 1968 is also on the NBI list.
No bridges in Ayer, Groton or Pepperell are considered in need of urgent attention.
According to Tom Donald, state project manager for the state's 5,000 bridges, "All the bridges are rated in priority from 1 to 5,000 based on severity of need, with 1 being the worst. From those, there are three categories of consideration where money is allocated to be spent for repair, rehabilitation or replacement."
States are given a chunk of federal money each year that is especially earmarked for bridges, each state establishes its own prioritization metric over three classifications.
In Massachusetts those groups are: "off-system bridges," which are not linked to the national highway system; and "on-system bridges," which are divided into highly-traveled overpasses and town centers, and the interstates themselves.
Many municipally owned structures are "off-system," which means that the individual cities and towns are responsible the maintenance of structures.
But, according to Donald, "We are the stewards of all the state's bridges. If work needs to be done, we can't force them (the towns) to pay for the projects."
So when the number came up for the Townsend bridges, specifically the Locke Brook bridge on West Meadow Road, the state began planning.
Preliminary site work began on the Locke Brook location early this month when a local drilling company took core samples to determine if the current topograhical composition can support a planned auxillary bridge that will be used while the main structure is replaced. The timetable for the project is still in flux but the end product will be a modern bridge of steel and concrete that will safely accommodate the 800 cars that cross it daily.
Other area bridges rated as poor are at least three "on-system" units in Chelmsford.
Three I-495 highway overpasses are bridges of concern, according to MassDoT's website. The Hunt and Westford road bridges over the highway, both built in 1961, are on the state's list, as is the North Road bridge, which serves 33,500 cars per day.
The next major project slated for the area is the Beaver Brook Road bridge, over Beaver Brook, in Westford. The $1.5 million rehabilitation project is scheduled for 2022, according to MassDoT.