The Longfellow Bridge was completed in 1906, and is today considered the most important historic bridge in the City of Boston, due to its prominent location over the Charles River, as well as its outstanding visual and architectural quality.
Originally called the Cambridge Bridge, it was renamed the Henry Wadsworth Longfellow in honor of the distinguished poet in 1924. The multimodal bridge carries trains for the Massachusetts Bay Transportation Authority (MBTA), motor vehicles, pedestrians and bicyclists. The bridge handles 28,000 motor vehicles and 90,000 transit riders on average each day. The structure consists of 11 original, open-spandrel, steel-arch spans with a total length of 2,132 feet, and the deck is approximately 105-feet wide. The bridge substructure is built of granite masonry and consists of 10 hollow piers and two abutments. The central bridge span is marked by four neo-classical, granite towers, which are the origin of the bridge’s popular nickname – the “Salt and Pepper” Bridge.
According to Miguel Rosales, the lead architect on the Longfellow and adjacent Frances “Fanny” Appleton bridges, as well as the president and principal designer of Boston-based Rosales Partners: “The primary aim of the rehabilitation work was to address the bridge’s structural deficiencies, upgrade its capacity and bring it up to date with modern codes while also preserving its visual and architectural character.” The abutments and approaches to the bridge also had to be slightly modified to allow for accessibility in compliance with the Americans with Disabilities Act.
The bridge was considered “structurally deficient” because of the poor condition of several steel elements, and it had deteriorated substantially since the last major restoration project was completed in the 1950s. The bridge’s ornate, cast-iron pedestrian railings were restored or replicated when missing and its granite masonry was cleaned and conserved. Original ornate bronze doors and wood windows were cleaned or recreated when missing with their original profiles and detailing.
A new functional and aesthetic lighting system was also installed to enhance usability of the bridge at night and highlight its main architectural features. Original historic lighting posts were replicated and placed along the bridge at the historic granite niches, which mark the location of the arches below. These new historically appropriate lamps and fixtures serve to enhance the pedestrian experience along the entire bridge. The historic lamps originally attached to the granite towers were also replicated and placed in their original locations. In both cases, carefully concealed LED light-fixtures were used preserving the exterior appearance but increasing sustainability.
Meanwhile, the interior of the main granite towers was illuminated to create a distinct presence at night along the river. LED linear lights were used to frame the historic windows to create a subtle glowing effect. In order to conceal the location of the linear fixtures frosted glass was used, and to provide sufficient lighting for the roadways on the bridge, new higher posts were designed that were inspired by the original historic catenary poles used along the old trolley lines. These new lampposts were located in the same positions as the original catenary posts along restored railings next to the trains. The steel arch spans were also enhanced with new lighting that is located under each of the 12 arches that comprise the spans over the river.
A distinct blue color was selected which complements and highlights the bridge from a distance. The fixture were carefully located and detailed as to not detract from the historic character of the bridge.
“After almost 15 years of involvement, I am very proud of the end results and the amazing positive reception that both the Longfellow and Appleton bridge have received,” Rosales wrote. “The support and enthusiasm of my Beacon Hill neighbors for both bridges is very much appreciated.” The landmark bridge has once again become a source of pride for the community due to its enhanced artistic merit and the innovative restoration and preservation of its historic architectural character and engineering significance including its state-of-the-art, new lighting system.