Marine Log - August 2007 - (Page 4) Nick Blenkey Senior Editorial Consultant Second Thoughts Don’t raise the bridge, lower the boxes N ew research commissioned by Lloyd’s Register and carried out by the U.K.’s Ocean Shipping Consultants indicates that the expansion of the Panama Canal by means of new and larger locks is now likely to lead to “a complete redefinition of container trades.” This includes a new ship definition: NPX—shorthand for New Panamax, the largest ship able to transit the expanded canal. These NPX ships, with capacities upwards of 12,500 TEU, will make routes between Asia and the U.S. East Coast the most cost-effective means to move freight in and out of the U.S. Midwest. Central to the success of the revitalized trades will be the ability of ships to call at New York. There’s just one problem: the Bayonne Bridge. “With an air draft of 46 meters (151 feet), this bridge currently poses a problem for nearly all post-Panamax ships currently in service and on order,” says Lloyd’s Register, which adds, “it is understood that the 75-year old bridge will eventually be raised.” Let’s take a little closer look at what’s involved. The Bayonne Bridge crosses the Kill van Kull, which is one of the busiest waterways in the world and runs between the southern tip of the Bayonne Peninsula and the north shore of Staten Island, joining New York Harbor with Newark Bay. The bridge is the third longest steel arch bridge in the world, and was the longest in the world at the time of its completion in 1931—beating the Syd- ney Harbor Bridge by two feet. It carries about 20,000 vehicles a day and is operated by the Port Authority of New York and New Jersey, which says it is “an important part of the regional system of arterial highways.” On Staten Island, it leads to the Verrazano-Narrows Bridge via the Martin Luther King, Jr. Expressway and the eastbound Staten Island Expressway (1-278). It also leads to the Goethals Bridge and Outerbridge Crossing via the westbound Staten Island Expressway. Even now, many ships traveling the Kill van Kull must pass under the bridge at low tide because there is not enough vertical clearance. The Port Authority has been looking to solve this problem through various options, including raising the bridge or building a replacement. How do you raise a steel arch bridge? The roadway would be removed and the bridge piers extended higher. New suspension cables would be installed on the existing superstructure, to suspend a new four-lane road about 35 feet above the current position. The price tag would be about $500 million. Under the $1 billion replacement bridge scenario, a new bridge would be built alongside the original bridge and would have at least 200 feet of vertical clearance. Either plan would be at least a three year operation after final approval by state and Federal governments—and would involve closing the Kill van Kull to navigation for a period. Clearly, the Panama Canal is likely to be widened long before than the bridge is raised! Lloyd’s Register is proposing interim NPX ship design solutions that will help operators to provide a competitive service from Asia to the U.S. East Coast —including New York—while the air draft under the Bayonne Bridge remains at its present status. The Panama Canal Authority says that an NPX vessel would have dimensions of 366m by 49m on a 15m draft. The Lloyd’s Register says this would enable ships with a capacity of 12,500 TEU to transit the new canal locks, carrying seven or eight tiers of containers on deck. To meet the current air draft restrictions in New York, however, a post-Panamax container ship would need to be limited to five tiers on deck. This, says Lloyd’s Register, requires a new approach to design—probably incorporating a “one third forward” bridge arrangement to maximize the ship’s container capacity. Lloyd’s Register says all this can easily be changed to get the on-deck tiers up to eight once the bridge has been raised. Whenever that might be! nblenkey@sbpub.com Dec. 5-6, 2007 Washington, D.C. Corporate sponsor www.marinelog.com 4 MARINE LOG AUGUST 2007 . . . is coming www.marinelog.com http://www.marinelog.com http://www.marinelog.com
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