Location

Bronx and Manhattan, NY

Services

Materials Analysis

Construction Documents

Field & Lab Testing

Construction Monitoring

Materials

Brick

Stone

Metal

Awards

2016 New York Landmarks Conservancy Lucy G. Moses Award

Completed in 1848, the High Bridge is New York City’s oldest standing bridge. It was built as part of the Croton Aqueduct system, which carried water from the Croton River in Westchester down to Manhattan. The 1,420 foot-long bridge spans the Harlem River between Manhattan and the Bronx. The top surface of the bridge serves as a pedestrian walkway between the two boroughs. The aqueduct’s original iron pipe still remains below the pedestrian walkway.

Due to neglect and unsafe conditions, the pedestrian walkway and bridge were closed to the public in the 1970s and remained so for 40 years. The restoration of the bridge included cleaning, patching, repointing and resetting granite stones as well rehabilitating the walkway. JBC worked on both the design and construction phases of the restoration. JBC was retained by Li Saltzman Architects to analyze the bridge’s natural cement mortar, painted finishes on metal elements, a waterproofing coating that was applied to the pedestrian walkway, and to perform metallurgical testing on iron elements including the massive aqueduct pipe. In the construction phase, JBC was retained by Schiavone Construction to assist with developing restoration procedures as well as periodic construction supervision.

Construction Phase Scope

• Cleaning, paint, and graffiti removal tests and recommendations.

• Written procedures for full restoration of masonry including crack repair, Dutchmen, patching, cleaning and repointing.

• Development of means and methods to protect the bronze lettering during abrasive cleaning of the stone.

• Monitoring and review, including periodic visits to report progress and quality assurance as well as review of submitted materials, means, methods, and shop drawings.