Two electrical substations serving load in Lower Manhattan were destroyed by the collapse of World Trade Center Building 7, where they occupied the two bottom stories. On Sept. 11, their combined 407-Mw capacity was loaded about 75%. Two 138-kv feeder cables serving them also were lost.
IMPROVED OUTLOOK |
Rana oversaw rapid restoration of electrical system. (Photo by Thomas F. Armistead for ENR)
Restoring electric power became the top priority, says Louis Rana, Consolidated Edison Co. vice president for Manhattan electric operations. To meet the immediate goalreopening the New York Stock Exchange on Monday, Sept. 17Con Ed technicians working round the clock ran 36 miles of what Richard P. Fogarty, substation and transmission chief engineer, calls "13-kv extension cords" around both sides of the site to the blacked-out areas.
Lines laid directly in the streets to save time were buried only at intersections to allow passage of emergency vehicles. The power was restored by 6:00 a.m. on Sept. 17 and the exchange opened on schedule. Ten days after the attack, power had been restored to the rest of the affected areas.
The priority then shifted to preparing for the summer peak load, requiring replacement of at least one of the stations. At an existing station in the vicinity of the South Street Seaport, five bays were available, complete with 138-kv feeders. Transformers ordered for another project were diverted to the replacement station. Vendors went all-out to meet emergency orders for switchgear and other equipment, says Fogarty. With that kind of cooperation and packaged equipment being installed in an existing building, the substation was in service April 27, after less than eight months. "Normally that takes two to three years," notes Rana.
Underground utility replacement also proceeded on a grand scale and a fast track. The emergency cable on the streets was replaced by 130 miles of new underground cable in nearly nine miles of trenches, says Rana. In late May, Con Ed removed the last of the temporary electric cable in the streets. Now, "the bulk of the underground work has been completed," he says.
A substation is planned for the building now being constructed on the 7 WTC site. The lower four stories will hold up to 10 transformers and associated switchgear, says Fogarty. Con Ed was hoping to have the station available by summer 2003, but "that's physically impossible now," he says. Con Ed plans to have its new station operating even as the building rises above it, but Fogarty says he will serve next summer's load with diesel generators, if necessary.
Telecommunications also reeled from the attack. "The square mile surrounding the World Trade Center is without doubt the most intensive square mile of telecom on Planet Earth," says David Johnson, spokesman for AT&T, Bedminster, N.J.
The WTC basement held the largest AT&T local network transport node in the U.S., says Kevin Lynch, vice president of field operations. With the capacity to handle more than 1.7 million voice messages at a time, it was a crucial telecom link serving all the financial exchanges in the nation's financial heart. "We essentially had to rebuild [the network] in the outside plan," says Lynch.
Following a rehearsed disaster recovery plan, AT&T restored service to the few customers remaining in the devastated area with a parking lot full of preloaded tractor-trailers in Jersey City, N.J. By Monday morning, the stock exchange could count on telecom as well as electricity.
AT&T now has dispersed replacement equipment to remote locations, making the system much less vulnerable to future attacks.
Workers cleared space for the new nodes in three separate buildings elsewhere in Manhattan and ran nearly 6,000 miles of fiber-optic cable up the east and west sides of the island to them from the area of the destroyed transport node. Of the cost, Lynch will say only that it was greater than $100 million.urning disaster into opportunity, utility companies and other service providers are using the wholesale reconstruction of Lower Manhattan grids and networks to upgrade, modernize and rationalize their systems.