HNTB served as lead designer on the design-build team for rehabilitation of the Metropolitan Transit Authority’s Long Island Rail Road Atlantic Avenue viaduct, a more than 100-year-old bridge that carries two tracks above six-lanes of vehicle traffic. Each weekday, more than 25,000 passengers travel between Jamaica, N.Y., and Brooklyn, N.Y., on the commuter rail line.

The project

Deterioration of the structure, which is 1.5 miles long and 26 feet wide, with 199 spans varying from 30 to 45 feet in length, required major rehabilitation, including:

• Replacing 189 spans
• Designing and replacing the longitudinal girder and cap beams
• Bracing
• Painting the entire structure
• Repairing columns
• Mounting fiberglass interior and exterior walkways for workers
• Installing improved lighting under the viaduct

Accelerated Bridge Construction

The phased project replaced the viaduct’s superstructure, its track and all utilities while trains continued to operate. The design-build team of Kiewit and HNTB completed all reconstruction activities during 54-hour weekend windows to minimize service disruption. Phases 1 and 2 of the project both were completed ahead of schedule without disrupting service.

Location: Long Island, NY

Client: Metropolitan Transit Authority