NEW YORK (NYTIMES) - At a subway station deep under Manhattan, a dingy room is filled with rows of antique equipment built before World War II. The weathered glass boxes and cloth-covered cables are not part of a museum exhibit, however - they are crucial pieces of the signal system that directs traffic in one of the busiest subways in the world.
Much of the signal equipment at that station, at West Fourth Street, is decades beyond its life span, and it is one of the main culprits plaguing the overburdened subway.
As New York City's sprawling subway faces a deepening crisis over delays, the Metropolitan Transportation Authority says that modernising the signals is a top priority. But the rollout of a new signal network is unfolding at a glacial pace even as the subway system is straining under the demands of a booming ridership. Two decades after the agency began its push to upgrade signals, work has been completed on just one line.
At the current pace, transforming every subway line could take half a century and cost US$20 billion (S$27.9 billion).
The signal system is the hidden, unglamorous backbone of the subway, controlling when trains can move down the tracks. But it is so outdated that it cannot identify precisely where trains are, requiring more room between them. And when it fails, trains stop, delays pile up and riders fume.
With a modern signal network, trains on the system could run closer together and therefore more frequently, allowing the subway to absorb more riders as the city's population grows.
New York could find inspiration overseas. Another major city with an even older - although smaller - subway system is also confronting soaring ridership: London. It is further along in its ambitious effort to modernise its signals and has emerged as a global leader in how to upgrade an aging subway, offering lessons to New York and other cities.
London has installed a computerised signal network on four of its 10 main subway lines, and work is underway on four more. Of New York's 22 lines, only the L train has the advanced signal system. A second line, the No. 7, may have it later this year, after a delay.
In New York, the plans have been hobbled by an anaemic schedule for upgrading tracks, a struggle to secure necessary funding and logistical challenges on a system that never stops running. Officials have also been reluctant to anger riders by closing stations to do the work. It took about a decade to complete the signal network on the L line, and work on the No. 7 line has already taken nearly seven years.
Confronted with infrastructure dating to the 1930s and a vast system of 472 stations (the most of any subway in the world), officials are forced to decide which projects to prioritise with limited financing. The transportation authority asked for US$3.2 billion for signal and communications work in its latest five-year capital proposal - about 10 per cent of its US$32 billion budget request - but US$400 million was cut from the plan approved by state leaders last year. The request reflected the need, and it was higher than in the previous two capital plans, when the agency requested US$2.4 billion, on average, for signals and communications.
Though many New Yorkers believe that Mayor Bill de Blasio runs the subways, the agency is, in fact, controlled by Governor Andrew Cuomo. Mr Cuomo, a Democrat, like the mayor, was focused on finishing the first segment of the Second Avenue subway on time, but critics say he has shown far less urgency about the deteriorating condition of the subway's signals. Transit advocates say the agency must pour more money into signal work and accelerate the schedule.
"Fifty years is way too far out there," Mr Thomas F. Prendergast, former chairman of the authority, said in his final interview before leaving the job in January. "We have to find a way to shorten that."
New York's more than century-old subway has been essential to the city's growth, but there is increasing alarm that after years of progress, the system is sliding backwards. To accommodate the nearly 6 million riders who take the subway on weekdays - the highest level since the 1940s - the authority is spending billions of dollars on new stations and more spacious trains.
The opening of the Second Avenue line and its ornately decorated stations in January was a high point for the agency, but the signal system - the least visible yet perhaps greatest challenge of all - remains mired in an analog era. Signal problems account for about 13 per cent of all subway delays and are the second most common reason for weekday delays, after overcrowding, according to statistics from the agency.
Worsening subway service is one of the many infrastructure challenges confronting the region, including recent commuting upheavals at Pennsylvania Station in New York. Amtrak, which owns the station, plans to close several tracks for repairs that will disrupt service this summer on New Jersey Transit and the Long Island Rail Road, two of the nation's busiest commuter railroads.
Most of New York's subway system still relies on antiquated technology, known as block signalling, to coordinate the movement of trains. A modern system, known as communications-based train control, or CBTC, is more dependable and exact, making it possible to reduce the amount of space between trains.
A computerised signal system like CBTC is also safer because trains can be stopped automatically. New York's quest to install the new system began in 1991, after a subway derailment at Union Square in Manhattan killed five people. The train operator was speeding after he had been drinking.
More than 25 years later, the authority has little to show for its effort to install modern signals. The L line began using computerised signals in 2009 after about a decade of work. A second line, the No. 7, should have received new signals last year, but the project was delayed until the end of this year.
The process is complicated. It requires installing transponders every 152m on the tracks, along with radios and zone controllers, and buying new trains or upgrading them with onboard computers, radios and speed sensors. The authority also had to develop a design and software that was tailored to New York's subway.
Over the years, the authority has kept pushing back the timeline for replacing signals. In 1997, officials said every line would be computerised by this year. By 2005, they had pushed the deadline to 2045, and now even that target seems unrealistic.
Upgrading the signals is expensive, but an even bigger challenge is scheduling work on such a vast system where ridership is always high, even on weekends, Mr Prendergast said.
"The money issue, as difficult as it is, is an easier issue to sort than how much work can the system sustain at one given period of time," he said.
As ridership exploded on the L line, which runs between Brooklyn and downtown Manhattan, the agency did not have enough train cars built to communicate with the new signals.
"It took way too long, but it was a confluence of things that made it take a while," said Mr Richard Barone, a vice president at the Regional Plan Association, an urban policy group that has studied New York's signals.
The authority awarded a contract for the No. 7 line work in 2010, but Hurricane Sandy struck two years later, damaging subway tracks and delaying the project. And officials have been reluctant to frustrate riders by halting train service for long stretches, leaving workers with few windows to finish the work, Mr Barone said.
Then there is the constant uncertainty over the authority's finances. State and city leaders feuded over the agency's current capital plan for a year, and the agency still does not know how Mr Cuomo will finance much of the US$8 billion he committed towards the pared-down US$29.5 billion five-year plan. Transit advocates say that having a stable funding source would benefit signal work and other long-term projects.
Then there is London. A close look at how it is attacking the same problems could provide something of a blueprint for New York.
As its population climbs, London is facing similar concerns about subway overcrowding. The London Underground, known as the Tube, opened in 1863 and is the oldest subway system in the world. It now carries about 5 million people each day, its highest ridership ever. The crowding at rush hour is so intense that officials sometimes must close certain stations.
The rollout of modern signals on four lines has significantly reduced delays, making travel across this huge city of nearly 9 million people more efficient. This month, the Victoria line will reach a peak of 36 trains per hour - compared with 27 trains per hour a decade ago, and among the highest rates in Europe. In New York, the Lexington Avenue line, the nation's most crowded subway route, runs a peak of 29 trains per hour.
On the Victoria line, which already has some signal upgrades, riders enjoy reliable service and a constant flow of trains.
"I've never been stuck waiting for a train," Mr Joe Brooke, a 20-year-old student, said as he rode the line on a recent afternoon. "It's convenient, easy, quick."
London has moved more quickly on signals because officials completed the work on each line faster as they gained experience, prioritised funding for the project and were willing to face commuter wrath when closing stations. The projects have required disruptive weekend closings and a major overhaul of the system's infrastructure.
"People think it's just a few computers - how could it be so expensive?" Mr Mark Wild, managing director of the London Underground, said in an interview at his office.
"It's new trains, new track, new power. The signals are a relatively small piece of the capital cost, but it's the bit that unlocks it."
The project to modernise the next four lines is expected to cost roughly £5.5 billion (S$9.9 billion) and increase capacity on those lines by a third. Funding in London is generally less challenging because the system relies on higher fares than New York and on a capital grant from the national government. But scheduling work is also easier because the subway has not traditionally run round-the-clock, as New York's system has. The Tube only recently introduced overnight service on some routes.
Over the years, officials learned from each line and settled on standard technology, Mr Wild said. The Northern line modernisation was completed in about three years - a shorter period than on other lines.
"The key thing to get across is: The duration to do these jobs gets shorter and shorter the more you do it," Mr Wild said.
Tube riders applaud the results. Ms Maes Al-Gabry, 25, who recently moved to London from New York, said she often found herself waiting - and waiting - on subway platforms in New York. On the Tube, a train arrives every minute or two.
"It's so much more reliable," she said as she rode the Victoria line on a recent afternoon.
London is also working to ease overcrowding by building a new line and buying roomier subway trains, with accordion-style connectors between cars. A new route called the Elizabeth line will open in London next year, with plans for 10 new stations and 42km of new tunnels. The plan, known as Crossrail, is the largest infrastructure project in Europe, costing about £15 billion.
But Transport for London, the agency that runs the Tube, has faced obstacles, too. In 2013, it cancelled a contract with Bombardier, a transportation company, over concerns that it could not complete signal work on four older lines on time, and started over with a different company.
The agency lost time and money, but officials learned from the mistake, said Mr Stephen Joseph, executive director of Campaign for Better Transport, an advocacy group.
"There's a feeling Transport for London knows how to do this now," Mr Joseph said.
New York subway officials are working to replace track and cable equipment on the lines with the oldest infrastructure and to move the No. 7 train to a modern signal system. Signals on the Queens Boulevard line will be upgraded next.
But in Queens, regular weekend closings on the No. 7 line have set off an uproar. Some people have moved rather than endure unending disruptions, said Councilman Jimmy Van Bramer, a Democrat who represents western Queens.
"We have people who are just at their wits' end," Mr Van Bramer said. "They're incredibly frustrated and incredibly angry, and there is no end in sight."
Mr Barone, of the Regional Plan Association, argues that New York should schedule longer closings to finish the work more quickly. Mr Van Bramer agreed that it would be better to simply "rip the Band-Aid" off by doing all the work at once.
Mr Wynton Habersham, head of the subway department at the transportation authority, said he would prefer longer closings, too, but the agency has to weigh the impact on riders.
"The reality is, if we had our druthers, we'd probably shut an entire line down to do a signal project," he said. "But to do that brings a lot of inconvenience and brings a lot of pain to our customers."
On a recent evening, Mr Habersham walked along the train tracks near 34th Street in Manhattan as workers replaced antiquated switches and cables. A signal system should last about 50 years, he said, but the one that guides trains through this slice of Manhattan has been in place for about 80.
"We're at a point now where it's getting difficult to maintain the system," he said. "We're maintaining it and it's safe, but it's 30 years beyond its useful life."