Friday, January 2, 2026

Maynard's Main Street Bridge Status

Maynard's Main Street bridge is tentatively scheduled for replacement starting the summer of 2028. The estimated budget is $8.4 million, a far cry from the $20,000 that the bridge it will be replacing cost back in 1922.

A bridge is rated “structurally deficient” if its deck, superstructure, or substructure is rated in poor condition, which is a rating of 4 or below on the National Bridge Inspection Standards (NBIS) rating scale. Per website https://www.fhwa.dot.gov/bridge/nbis.cfm, "...the NBIS are the standards established over the safety inspections of highway bridges on public roads throughout the United States. The U.S. Congress originally required the Secretary of Transportation to establish these standards in 1968. The original NBIS was published in 1971, creating our Nation's first nationally coordinated bridge inspection program. Periodic and thorough inspections of our Nation's bridges are necessary to maintain safe bridge operation and prevent structural and functional failures. Updates to the standards have been made over the years, most recently in 2022. These updates recognize technological advancements, research results, and experience in administering the inspection program."

Plaque on the Main Street bridge (click to enlarge). This plaque and
one for the Walnut Street bridge were installed on Armistice Day,
November 11, 1923, in memory of those who served in the named wars.  


The mass.gov website https://gis.data.mass.gov/datasets/MassDOT::bridges/about has a link to a map of all bridges in Massachusetts with reports of the most recent inspections for each bridge. Maynard has three Assabet River bridges that are more than 100 years old: Walnut Street, Main Street and Route 117/62 toward Stow. The latter is also known as the Ben Smith bridge, as it is not far downstream from the Ben Smith dam. (The dam so-named because it was Ben Smith who sold the land to Amory Maynard and William Knight to build the dam that would power their mill.) These were all constructed as rebar-reinforced concrete bridges, with an expected lifespan of 50-75 years. The Walnut and Route 117/62 bridges were recently scored as six overall, i.e., "Fair", with no four scores for deck, superstructure or substructure. In contrast, the Main Street Bridge - constructed in 1922 - had an overall score of four, i.e., "Poor", with four for deck and superstructure and five for substructure. The image shows some of the deteriorating concrete.

A search for future bridge projects identified Project #604564 as a replacement of this Massachusetts bridge #M-10-004, with a planned start date as summer of 2028. The existing bridge has a curb-to-curb with of 36 feet with 6.8 foot sidewalks of both sides. The plan calls for full-depth reconstruction of 300 feet beyond the bridge itself on both approaches, which would include not just Main Street but also the Walnut Street connection. The demolition, removal and replacement will be conducted in stages to always allow one lane of traffic in both directions plus pedestrian access during all of the demolition and construction, much as was accomplished for the Waltham Street bridge a few years back. This may require a temporary sidewalk bridge, as did Waltham.

The 1872 Main Street bridge, standing on Walnut Street and
looking west. The farthest building was "Assabet House",
 a large boarding house demolished in 1962 to make room
for the present-day post office, which opened in 1963. 
Photo courtesy of Maynard Historical Society. 
The estimated cost of the project is on the order of 8.4 million dollars, to be funded primarily through the Federal Transportation Improvement Program. Bridge replacement projects are notoriously slow - state records show initial consideration dating to 2005, then the Notice To Proceed (NTP) to begin negotiating a contract, issued in 2022, with actual work start scheduled for 2028. 

The history of a Main Street bridge over the Assabet River dates back to 1849, with replacements in 1872 and 1922. The 1872 bridge was of steel construction, as was the Walnut Street bridge of the same year. Both were replaced in with rebar-reinforced concrete bridges. The contract was awarded to F.B. Saunders of Framingham, who had bid $34,485 to do both bridges, in August of 1922. (The smaller Florida Street bridge had been replaced in 1919 for $6,000.) In the photo, the tracks were for the electric trolley that serviced Hudson, Stow, Maynard and Concord, with a branch to Acton, over the years 1901-1923. 

The first bridge owed its existence to the woolen mill. Under the auspices of Amory Maynard and William Knight, a woolen mill was constructed in 1846. At that time there was a railroad line passing through South Acton, connecting Fitchburg to Boston, that had become operational in 1844. The mill, however, was on the south side of the Assabet River, with no convenient way for horse-drawn wagons to bring raw wool in and finished goods out from the railroad station at South Acton. The bridge across the Assabet was completed in 1849.* This allowed wagons loaded with wool or other goods to more conveniently connect to the road north to South Acton. That road (now Route 27) also crossed Concord Street, thus providing a connection to Concord to the east and Stow to the west. The east/west road was ancient, as on April 19, 1775, Stow Minutemen had marched on it toward Concord to confront the British troops that had forayed out from Boston to seize guns and other militia supplies.  

*By 1850, with a lot of lobbying by Amory Maynard, a railroad spur from South Acton reached what was then informally named Assabet Village (later incorporating as Town of Maynard in 1871), and then extended to Marlborough in 1855. In Assabet Village, a short railroad spur was created directly into the woolen mill. In addition to transporting raw wool and finished goods, after the Civil War the railroad was delivering coal, and in that way allowing the Assabet Mill to convert from water power to coal-fueled steam engines. The mill also had a coal gasification facility to provide gas for gaslight for the mill and for the town's streetlights, and then later a generator for electric lights. Over the following decades Maynard's mill becoming the largest woolen mill in New England. It closed in 1950.