Williamsburg Bridge, Contract 7

Development Team

Owner: New York City Department of Transportation, Division of Bridges, NYC
Prime Contractor: Yonkers Contracting Co. Inc., Yonkers, N.Y.
Prime Engineering Consultant: Consoer Townsend Envirodyne (CTE) Engineers of New York Inc., NYC Design Engineer/Construction Support
Services: The Parsons Transportation Group, NYC

The Williamsburg Bridge turns 100 this year.

The vital link in the city's transportation system carries eight lanes of traffic, two mass transit rail lines (the R and the N trains) and a pedestrian walkway, funneling 100,000 vehicles and 90,000 transit riders between Brooklyn and lower Manhattan daily.
During a routine biennial inspection of the bridge in 1988, the Parsons Transportation Group discovered extensive deterioration of the steel girders, mainly on the approaches, and determined that the floor beams under the railroad tracks were in poor condition.

In 1991, the city's Department of Transportation began a long-term program to repair the bridge without shutting it down. The work was split into eight contracts. Contract 7, which included the reconstruction of the Manhattan-bound roadways and the walkway, was completed last year.

The completion of the $230 million project was significant because it meant that after 11 years of work, all of the bridge's supports, roadways and rail tracks had been rebuilt. (The eighth and final contract will strengthen the main tower and reinforce the top chord of the stiffening truss.)

The work for Contract 7 was designed by Parsons, with Consoer Townsend Envirodyne Engineers of New York Inc. serving as the prime engineering consultant and Yonkers Contracting Co. Inc. working as the prime contractor.
Because there was no space for onsite fabrication and storage, the 24 truss sections needed for the Manhattan approach to the foot walk were manufactured at a fabrication yard in Red Hook, Brooklyn. Each truss section weights 90 tons and is 25 ft. wide, 125 ft. long and 12 ft. high, so getting them on site was no easy task.

Each truss was loaded onto a barge, floated up the East River, off loaded onto an especially large truck similar to the one used for the space shuttle, driven across the FDR Drive and then up North Delancey Street. From there they were lifted into place with two cranes.

The construction team received permission to stop traffic on the FDR once a week for a maximum of 15 minutes - at 1 a.m. Most of the trusses were moved and placed early on Wednesday mornings.

Another big part of the job was building the foundation for the new approaches to the bridge. It involved the installation of 2,500 piles, each with a capacity of 150 tons - the largest number and the highest-capacity foundation of its kind in the country.
The project was completed June 10, about 50 days ahead of schedule.