Best Highways/Bridges: Bronx Whitestone Bridge Rehabilitation

Originally opened in 1939 as a four-lane span, the Bronx-Whitestone Bridge has expanded over the years to accommodate the roughly 200,000 vehicles that cross over it daily. However, like many aging structures throughout the metropolitan area, it was in great need of repair to bring it up to 21st-century safety standards.

The $192.8-million rehabilitation of this major artery between the Bronx and Queens included construction of 15 double-arch piers with mini-pile foundations; replacement and widening of the steel deck to 12 lanes from 10; and demolition and reconstruction of the 2,091-ft Bronx approach structure.

Under an aggresive 42-month schedule, the team was required to keep at least five lanes of traffic open at all times throughout construction. It succeeded by implementing a complex staging plan that used all space available. The team, for example, built new concrete bridge piers in advance of deck demolition under the existing structure and installed extensive temporary supports for the existing viaduct. This allowed sections to be demolished in stages while remaining sections could continue to carry traffic.

The team also installed specialty equipment to monitor the vibration impact of remediation and installation work. With these measures, it could ensure that there was no roadway disturbance and that ongoing work would not impact the public.

The high-profile project required major coordination and communication efforts. Site access was limited—the entry and exit point was located under a viaduct to avoid impacting adjacent wetlands. Given that, logistics and delivery schedules were carefully planned so that more than 13 million lb of steel—as well as concrete and other materials—were received and placed on schedule at the site.

Diligent communication was also critical in keeping work running smoothly. The team continually relayed information to stakeholders that included government agencies, subcontractors and the public.

The project was delivered on time and on budget.

Best Projects judges noted the team's success in keeping five lanes open on a bridge that handles 5,000 vehicles an hour and called the project innovative and "technically more complex than others."

Bronx Whitestone Bridge Rehabilitation, Bronx & Whitestone, N.Y.

Key Players

Owner Metropolitan Transit Authority, Bridges and Tunnels

General Contractor Conti Enterprises Inc.

Lead Designer A joint venture of Parsons Brinckerhoff and WSP Sells

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