On December 17, the New York State Thruway Authority unanimously selected a winning proposal for the replacement of the Tappan Zee Bridge in the Lower Hudson Valley. The authority picked the cheapest of three proposals it had under consideration—the $3.1 billion dollar design by Tappan Zee Contractors. Construction is scheduled to begin in early 2013 and completion is projected for 2018.
The winning design features a twin roadway with a central 350-foot-long, composite-deck, cable-stayed span supported by four reinforced concrete towers that resemble capital "As" turned on their heads. The outwardly inclined towers will be robust enough to handle the loads of rail and/or select bus rapid transit, which may be added to the project at a future date.
The replacement will be the single largest bridge project in New York history, with a construction price tag of $3.1 billion plus another $500 million to $800 million in environmental mitigation, management, and other costs—still considerably less than the original $5.2 billion estimated by the state. The state also enacted special legislation for the project that requires the design-build contractor to cover cost overruns and delays.
Winning design team Tappan Zee Contractors is a consortium between, among others, Pennsylvania-based American Bridge Company (the builder of the original crossing) and Texas-based Fluor Corporation. Those firms were members of the team that designed and constructed the recently completed San Francisco-Oakland Bay Bridge replacement. The team will make use of special heavy-lifting equipment it constructed for that project to cut costs and time from the Tappan Zee replacement, a factor that gave the firms the confidence to enter a bid that was approximately a billion dollars cheaper and a year faster than its competitors. It also proposes to reduce the amount of dredging necessary from 1.8 million cubic yards to less than one million cubic yards, reducing environmental impacts, costs, and the schedule.
Tappan Zee Contractors’ proposal beat out a $4 billion proposal by a joint venture involving Kiewit Infrastructure and Skanska USA and a $3.9 billion proposal from Bechtel Infrastructure and Tutor Perini. Those proposals required closer to six years to complete and required more dredging.
The existing Tappan Zee Bridge was completed in 1955. The 3 ½-mile-long crossing spans the Hudson River at its second widest point, connecting Rockland and Westchester counties 25 miles north of New York City. It serves approximately 138,000 vehicles per day, far more than it was designed to accommodate. Traffic jams and accidents are a regular occurrence at the crossing, a factor that kicked off replacement talks more than a decade ago. The 2007 collapse of the I-35W bridge in Minneapolis added a sense of urgency to the project, though no significant progress was made on the project until Governor Andrew M. Cuomo took up the cause when he entered office in 2011.