Bridge 'unbuilding' clears the way for neo-Panamax containerships in NJ

Navigational clearance for the new generation of neo-Panamax containerships coming into New Jersey container ports will be ready this summer, as workers dismantle the original 85-year-old roadway of the Bayonne Bridge in a process termed "unbuilding" by the Port Authority of New York & New Jersey.

The rebuilt span over the Kill Van Kull channel leading to the ports of Newark and Elizabeth will be 215’ above the water — 64’ higher than the original bridge — finishing a key part of the Port Authority's plan to compete with other East Coast ports.

The higher vertical clearance will let containerships built for the widened Panama Canal clear the waterway between Bayonne, N.J., and Staten Island, N.Y.  Local pilots and tugboat companies have been preparing for the new ships with training and ordering bigger, more powerful tugboats.

The old span of the Bayonne Bridge is visible beneath the elevated new one. Photo by Mike Dombrowski, Port Authority of New York & New Jersey.

The current four-month phase of the bridge project is removing 9,800 tons of steel and concrete, a tricky task to perform safety above the heavily trafficked channel. This part is actually six months ahead of schedule, according to Steven Plate, the Port Authority chief of major capital projects.

Sparks fly as workers separate the 85-year-old steel floor beams and girders that once made up the lower span of the Bayonne Bridge. Photo by Mike Dombrowski, Port Authority of New York & New Jersey.

Engineers divided the old span into sections called “panel points,” concrete squares 40’ to a side. They are supported by steel girders and floor beams, suspended by cables from the original bridge arch that supports both the old and new roadways.

Cranes equipped with giant saws cut each panel point into four 20’ squares, which are then lifted away to expose the steel support structure. Workers cut up the steel and remove it, then proceed to the next section.

The material is trucked away for recycling, as the old roadway retreats day by day — a process captured in a time lapse video prepared by the Port Authority’s Raphael Azucar and Conrad Barclay.