Tappan Zee Constructors has announced that they have set a date for the use of demolitions to bring down the old Tappan Zee Bridge that has damaged sections.
According to the company project engineers, the decision to use explosives was made after the September discovery that the bridge's east anchor span, which was already out of service, was damaged but stable with certain key components highly stressed.
Since that time, the span has been closely monitored, and it has been determined that the original removal plan is no longer the safest method of removal and that controlled demolition is the safest way to lower and remove the span, the company said.
TZC has hired demolition and salvage experts to perform the work that is scheduled to being at 9:30 a.m. on Saturday, Jan. 12, 2019, the company said.
The charges will be used to bring down the vertical members supporting the span, allowing the demolition team to safely lower the span eastward, away from the main navigation channel, using specialty marine salvage equipment. Marine salvage experts will then remove the material from the river during the following weeks.
The steel will be recovered with the assistance of chains, previously laid on the riverbed. The chains will support the salvaged structure in the river, enabling TZC to place the material on barges for removal from the project site.
During the demolition period, the Hudson River’s main navigation channel will temporarily be closed at 7:30 a.m. for approximately three hours and traffic on the New York State Thruway (I-87/I-287) – between exits 11 (Nyack – South Nyack –
US Route 9W) and 9 (Tarrytown, Sleepy Hollow – Route 9) - will be stopped in both directions by State Police at 8:55 a.m. for approximately 45 minutes.
In addition, the U.S. Coast Guard is planning to establish a 2,500-ft. safety radius around the controlled demolition site during the operation.
“Through extensive engineering analysis, it has been determined that this is the safest method to proceed with lowering the span given its current state," Tappan Zee Constructors said in a statement. "TZC has worked with local, state, and federal agencies to review the controlled demolition plans and subsequent operations to remove the steel from the Hudson River. Throughout the planning and execution of this operation, the safety of our workers and the traveling public is our top priority.”
Over the past week, TZC has been meeting with local officials to inform them of the details. They have been told that no residential areas are within the safety zone, and local residents are not expected to be affected by the blasts, which will sound like fireworks, the company said.