Boston’s beloved Longfellow Bridge has been magnificently restored, marking the completion of a significant granite refurbishment endeavor. This project saw United Stone leading the charge, involving meticulous onsite blasting activities as well as the careful deconstruction of the bridge’s famed Rockport granite “salt and pepper” towers. These pieces were then shipped to Charlestown workyards for specialized restoration before being pieced back together on-site, blending traditional craftsmanship with contemporary building methods. United Stone’s artisans expertly rejuvenated the intricate granite sculptures and massive stone blocks using advanced blasting technology tailored for this unique application.

The restoration process employed by Sponge-Jet is tailored to each project’s specific finish desired by architects or preservationists, allowing for a customized approach through the careful selection of media and blasting pressures. This technique ensures the granite’s surface is meticulously cleaned without causing harm to the stone, effectively removing stains, chlorides, and other impurities while keeping airborne dust to a minimum.

Remarkably, parts of the Longfellow Bridge remained accessible to the public during the restoration, with pedestrian and cyclist traffic continuing unimpeded as conservation efforts unfolded just a short distance away.

Jeff Hartwell, the Vice President of Operations at United Stone and Site Inc., praised the Sponge-Jet technology for its effectiveness and minimal environmental impact. “The Sponge-Jet system proved invaluable on the Longfellow Bridge project, demonstrating both its efficiency and environmental friendliness. After the initial setup, a small team could carry out the work seamlessly. It’s hard to overstate the benefits of this eco-friendly method over traditional acidic cleaning or manual scrubbing techniques,” Hartwell shared.

This project not only revitalized a key piece of Boston’s infrastructure but also showcased the seamless integration of eco-conscious restoration practices with historic preservation efforts, ensuring the Longfellow Bridge’s legacy for years to come.