Back On TrackBy Elizabeth Bennett | Posted 2005-03-08 Email Print
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A blaze in a New York subway station threatened to derail service for yearsbut a resourceful manager helped get the trains rolling again in 10 days.Tracy Bowdwin, nighttime assistant chief signals officer for New York City Transit, spent Sunday, Jan. 23, making sure snow hadn't piled up on the rails and switches were working properly following a snowstorm. En route to his downtown Brooklyn office from a subway station in Queens, he got the call on his BlackBerry.
Fire in the Chambers Street station. Bowdwin's first reaction: "We see track fires all the time." Second reaction: "When they told me the signal system was starting to fail, I knew I was in trouble."
The station fire, the source of which is still unknown, was only the second in a century to destroy a relay room, the nerve center of subway operations.
These rooms contain the relays, circuits, signals, fuses, batteries, cabling and other equipment that safely space, track and redirect trains passing through a station. Without relays to power the signals, service is not possible.
The Chambers Street room was home to 57 signal relayselectrical contacts, wires and coils in a package a little larger than a coffee cancirca 1932.
Welcome to crisis management on the fly. The biggest goal in this case was getting 580,000 New York City commuters to work the next day, on tracks that run along the West Side of Manhattan. Toss in a public statement from the city's transit authority president that it would take three to five years to bring back the affected A and C lines, and you're describing a recipe for continuing chaos.
Here's how Bowdwin and his underground cohorts got the A and C lines running again in 10 days, instead of years:
Phase One: Stay Calm, Assess, Communicate Well
When Bowdwin got his first call, he kept his emotions in check. "I've been through a lot of signal failures," he says. "It's not my job to get excited."
Within 20 minutes, Bowdwin was at a lower Manhattan station that connects to Chambers Street. Acrid smoke filled a platform about 1,900 feet from the fire, but Bowdwin knew what was needed: a quick damage assessment, an inventory of necessary materials and a project road map updated as often as hourly.
Flashlight in hand, Bowdwin sized up the damage through charred, wet electrical parts. "The whole place was a total loss and all the relays were burnt up," he says. "They're the most important part." His report to superiors: an inoperable signal system in at least the Chambers Street station, a destroyed relay room and 4,000 feet of track in "dark territory"an area that can't be monitored.
Meanwhile, subway officials were sending out mixed signals about the time it would take to recover. On the evening of the fire, Lawrence G. Reuter, president of New York City Transit and its umbrella agency, the Metropolitan Transportation Authority, made this statement: "This is going to have an impact we're guessing from between three to five [years]; we'll know better in the next week or two as the engineers evaluate it."
Phase Two: Set First Milestones, Deliver
With the damage assessed and necessary labor lined up, Bowdwin set his first milestone: Restore service by the next morning's commuter rush.
With signals down and no way to direct trains through the "blind" areas, Bowdwin's crew created an "absolute block," which limits an area to the passage of one train at a time. That meant six trains per hour could safely travel through the damaged station. Normally, 25 did.
The A train ran a drastically reduced schedule that day, Monday, Jan. 24. The C train could be diverted temporarily to the F line, which runs parallel to the C and then about a mile north of it in lower Manhattan.
To restore limited service, teams of signal workers checked the 40 or so signals in the adjacent stations for damage and slated them for rewiring. Workers then manually secured the 15 switch points that had run on relay room power. Clamps and wooden blocks prevented tracks from moving.
For train conductors and passengers, the absolute block meant delays. For three days, the A train rolled into the Canal Street, Chambers Street and Broadway-Nassau stations and sat until the motorman got the all-clear from a transit worker communicating with a colleague at the next station. Once cleared, the train lurched through the darkness with the help of lantern-carrying, whistle-blowing "flaggers."
The next nine-plus days would include 12-hour shifts of signal operators, signal engineers and capital construction emergency workers. The goal: get more signal control back. Engineers designed circuits and tracked down extra signals and cable (20,000 feet of it) to get to "automatic block," service with limited signal control but no switching ability.
Circuits for 15 of the downed signals were rewired via spare relays kept in cases between stations. At the end of each shift, Bowdwin and his daytime counterpart, Vito Geloso, updated a Microsoft Excel spreadsheet. These entries were used to outline tasks for the next shift and inform superiors of progress.
By Feb. 210 days after the fire at Chambers Streetrush hour service on the northbound lines was at 70% of normal frequency, and at 80% on southbound trains to Brooklyn. Frequency of service is expected to return to 100% in May or June when all automatic signals will be restored. But trains won't be able to switch tracks or go in reverse.
Phase Three: Plan Ahead
When New York City Transit rebuilds the Chambers Street relay room, it won't go back to Depression-era technology. The agency's capital program management division will feature Chambers Street in its plan to convert the subway system to communications-based train control (CBTC) systems. CBTC uses two-way digital radio-frequency communication between "intelligent" trains that continuously calibrate their own speed and location, and "zone controllers," a network of distributed computers located at each interlocking (switch) point to direct all the trains and tracks in a zone.
The agency plans to upgrade the entire network to CBTC, starting with the Canarsie L line in July. Between procuring funds and a work schedule restricted to nights and weekends, the upgrades could take 30 to 35 years, systemwide. CBTC "will greatly reduce the uncertainty by precisely locating the train," according to chief signal officer Nabil Ghaly. Optical lasers on the belly of each car will scan transponders positioned about 600 feet apart on the side of the tracks. The train will relay that information via data radios to the zone controllers, giving them a digital map of all trains in the area.
With enhanced monitoring, New York City Transit can cut the distance between trains to increase frequency and reroute lines quickly. Engineers will make design and operational changes directly into the zone controller database, rather than hard-wire track equipment made by a two-person squad trained in the art of subway-part smithing. Ghaly says the transit authority will first have to create tools to verify and modify the database.
So how long will it take to revamp the Chambers Street relay room with the new two-way train control system?
"We could build it in seven or eight months if we went full tilt, but that's not realistic," Bowdwin says. "We would have to design it, fund it and shut down service to build it." So what is realistic? Three to five years.