The Lechmere Viaduct is a concrete

arch bridge An arch bridge is a bridge with abutments at each end shaped as a curved arch. Arch bridges work by transferring the weight of the bridge and its loads partially into a horizontal thrust restrained by the abutments at either side. A viaduct (a ...

connecting the West End neighborhood of Boston to

East Cambridge, Massachusetts East Cambridge is a neighborhood of Cambridge, Massachusetts. Referred to in modern times as Area 1, East Cambridge is bounded by the Charles River and the Charlestown neighborhood of Boston on the east, the Somerville border on the north, Bro ...

. Opened in 1912, the

viaduct A viaduct is a specific type of bridge that consists of a series of arches, pier (architecture), piers or columns supporting a long elevated railway or road. Typically a viaduct connects two points of roughly equal elevation, allowing direct over ...

carries the

MBTA The Massachusetts Bay Transportation Authority (abbreviated MBTA and known colloquially as "the T") is the public agency responsible for operating most public transportation services in Greater Boston, Massachusetts. The MBTA transit network i ...

's Green Line over the Charles River. It is adjacent to the Charles River Dam Bridge, but structurally separate.

History

Construction

When the northern section of the

Tremont Street subway The Tremont Street subway in Boston's MBTA subway system is the oldest subway tunnel in North America and the third oldest still in use worldwide to exclusively use electric traction (after the City and South London Railway in 1890, and the B ...

opened in 1898, surface cars entering the subway from East Cambridge had to cross Craigie's Bridge and proceed on surface streets to the

Canal Street incline The Canal Street incline (also Canal Street portal) was a ramp connecting two transit tunnels in Boston with surface and elevated lines. It was located in the Bulfinch Triangle between North Station and Haymarket Square in two blocks bounded by C ...

. The trip from

Lechmere Point Lechmere Square ( ) is located at the intersection of Cambridge Street and First Street in East Cambridge, Massachusetts. It was originally named for the Colonial-era landowner Richard Lechmere, a Loyalist who returned to England at the beginnin ...

over the bridge was slow and prone to delays. On June 20, 1907, construction began on one mile of elevated track connecting the Canal Street incline to East Cambridge. The project's centerpiece was the 12-span, -long viaduct crossing the Charles River. The spans are numbered 1 to 12 from south to north. Ten of the spans are arches; span 3 is a bascule drawbridge over the Charles River channel through the Charles River Dam Bridge, while the span 12 (the northernmost span) is a girder span over the Gilmore Bridge approach. The viaduct connected to the Causeway Street Elevated on the south (Boston) side of the river, and a short steel elevated section (the Lechmere Elevated) that sloped down to Lechmere Square on the north (East Cambridge) side. The first streetcars crossed the bridge in revenue service on June 1, 1912, shortening the ten-minute trip from Lechmere Square to the subway to just three minutes. The building of the massive structure was done entirely by the

Boston Elevated Railway The Boston Elevated Railway (BERy) was a streetcar and rapid transit railroad operated on, above, and below, the streets of Boston, Massachusetts and surrounding communities. Founded in 1894, it eventually acquired the West End Street Rai ...

, without use of subcontractors. The BERy opened Lechmere station on July 10, 1922, as a transfer point between the Cambridge streetcars and the subway cars. This prevented traffic delays affecting the surface cars from propagating into the subway, and allowed the underground service to use three-car trains, which were too long for safe

street-running A street running train is a train which runs on a track built on public streets. The rails are embedded in the roadway, and the train shares the street with other users, such as pedestrians, cars and cyclists, thus often being referred to as r ...

. In 1935, a citizen's group proposed to widen the viaduct into a four-lane expressway to accommodate an extension of the

Mohawk Trail The Mohawk Trail began as a Native American trade route which connected Atlantic tribes with tribes in Upstate New York and beyond. It followed the Millers River, Deerfield River and crossed the Hoosac Range, in the area that is now northwester ...

; transit service would have been rerouted into a new parallel subway. On August 20, 1955, the MTA opened Science Park station as an

infill station An infill station (sometimes in-fill station) is a train station built on an existing passenger rail, rapid transit, or light rail line to address demand in a location between existing stations. Such stations take advantage of existing train ser ...

on the steel approach span of the viaduct over Leverett Circle, just south of the southernmost arch span. It serves the Boston Museum of Science and the West End.

Service disruptions and rehabilitation

Lechmere Viaduct rehabilitation work, July 2021

On June 25, 2004, service over the viaduct was suspended as the Causeway Street Elevated was removed, and the surface and elevated platforms at

North Station North Station is a commuter rail and intercity rail terminal station in Boston, Massachusetts. It is served by four MBTA Commuter Rail lines – the Fitchburg Line, Haverhill Line, Lowell Line, and Newburyport/Rockport Line – and the Amtra ...

were consolidated into a new underground "superstation". This left the Lechmere Viaduct and Lechmere Elevated as the sole remaining elevated lines in Boston. A new portal was built off Martha Road, with a new concrete bridge connecting to the viaduct just south of Science Park station. Service to Lechmere resumed on November 12, 2005. The incline from the 2005-built tunnel to the Lechmere Viaduct is the steepest grade on the entire MBTA subway system. The viaduct was again closed from April 30 to November 4, 2011, as Science Park station was rebuilt with accessible platforms and new elevators. As part of the

Green Line Extension The Green Line Extension (GLX) was a construction project to extend the Massachusetts Bay Transportation Authority (MBTA) Green Line light rail system northwest into Somerville and Medford, two inner suburbs of Boston, Massachusetts. The p ...

project, the northern section of the Lechmere Elevated was removed and connected to a new elevated structure east of Route 28. The original Lechmere station was replaced with an elevated station on the new structure. The viaduct was closed (with service cut back to North Station) on May 24, 2020, with reopening then expected in April 2021. Demolition of the northern section of the Lechmere Viaduct began on June 6, 2020. Only the steel section of the viaduct north of the Gilmore Bridge was replaced; the main concrete span was restored to support Green Line Extension service and future Type 10 vehicles. By July 2021, the rehabilitation project was 83% complete; track and signal work were complete, power work nearly complete, and concrete repairs under way. Substantial completion was reached on March 16, 2022. Only the E branch service used the viaduct at the time of its 2020 closure; the B, C, and D branches terminated in downtown Boston. With the Green Line Extension complete, the D and E branches run across the viaduct: the E branch to , and the D branch to . Service over the viaduct resumed with the opening of the Union Square Branch on March 21, 2022. The Union Square Branch will also be closed from August 22 to September 18, 2022. The closure allowed for wire replacement on the Lechmere Viaduct, increasing speeds from to , as well as final integration of the Medford Branch and other work.

References

External links

MBTA – Lechmere Viaduct RehabilitationMACRIS – East Cambridge Viaduct - Lechmere Viaduct
{{MBTA Green Line (MBTA) Transportation in Cambridge, Massachusetts Light rail bridges