STAMFORD -- As the investigation continues into the cause of Wednesday's power failure that pulled the plug on Metro-North's busy New Haven Line, a railroad spokeswoman said the plan to take a secondary electrical line out of service had been planned and tested over the summer.
"We ran extra trains in that section and put extra load on the grid and it was decided mutually between Metro-North and Con Edison that there wouldn't be a problem," Metro-North spokeswoman Marjorie Anders said.
Though it may take officials weeks to determine the cause, it appears the 138,000 volt line that was left to bear the burden of energizing trains along an eight-mile stretch of track in Westchester County, N.Y., from Pelham to Rye became overwhelmed and superheated.
This month, Con Edison de-energized one of the two 138,000 feeder cables in the Mount Vernon substation to accommodate Metro-North's ongoing $50 million project to increase the system's capacity and support more service in the future in the area, Anders said.
During the summer tests the railroad ran a higher than normal number of trains through the area on the 36-year-old feeder cable to see if it could bear the additional load, Anders said. The normal design life of the feeder cable is 30 years, she said.
After the tests, Metro-North Railroad and Con Edison deemed it unlikely that the primary 138,000 volt feeder line would fail due to being overloaded by the railroad's traffic through the area, Anders said.
Establishing a secondary power source linked to Con Ed's grid as a backup in the event of failure would cost millions and didn't appear warranted because the single feeder showed no cause for concern, Anders said.
"We thought plenty about this and it was considered a low risk," Anders said.
On Thursday, a Con Edison spokesman said the utility had yet to diagnose the cause of the electrical failure of a feeder cable that crippled Metro-North's New Haven Line because the cable is superheated and is being cooled by liquid nitrogen so it can be inspected.
On the first day of running a reduced service plan requiring transfers in Stamford from electric to diesel trains to reach Grand Central Terminal, many New Haven Line riders seemed to heed the advice of officials who urged them to carpool or telecommute, due to the limited number of seats. The number of New Haven Line riders using Metro-North dropped to around 19,000, roughly half the normal ridership during a regular weekday rush hour with 5,800 of them riding the Harlem Line, or about 25 percent higher than normal, according to Anders.
About 2,100 took Metro-North's bus shuttle from Rye to White Plains to take Harlem Line trains, Anders said.
The schedule, which provides about a third of the usual seats of normal service is expected to remain unaltered until voltage is restored to the stretch of track, Anders said.
On Thursday morning, the 9:10 a.m. train leaving Stamford for Grand Central Terminal pulled into the station with less than half the seats full when it pulled out. David Ashbery, a New Haven resident, said that the need to transfer at the Stamford station only slightly inconvenienced him.
"I'm originally from New York where the trains have been much later so this is really nothing but a slight setback," Ashbery said.
After arriving in Stamford yesterday David Meeson of Stratford switched tack and called a friend to pick him up to get to work at his Harrison, N.Y., office. Meeson said he did not know about the service disruption until Thursday morning and didn't want to gamble on the arrival of the next local train to Rye, N.Y.
"I'm stressed out," Meeson said. "I can't be late every day to the office. I'm going to have to stay late at the office."
Louis Nario of West Haven said he was unaware of the electrical failure and accompanying service reductions until he got to his station. At his home station public address announcements didn't announce the train he was waiting for was late for arrival.
"The only problem was getting to Stamford," Nario said.
Allan Drury, a Con Edison spokesman, said the utility had still not determined the cause of the cable's failure because the utility was still working to bring the superheated line under control so it could be worked on.
"There are multiple steps we have to take and those steps have to be taken in sequence," Drury said. "And it all has to be done to very specific engineering specifications."
Drury said the company has to clean up the coolant that normally protects the cable that leaked when the cable burst, and also freeze oil in several reservoirs to stabilize the line, Drury said.
"Our focus is now on two things: repair the feeder that failed yesterday morning and working with Metro-North to find alternate ways to power the line and get more trains back on the tracks," Drury said.
While the summer tests might have shown one feeder cable would be satisfactory, Otto Lynch, of the American Society of Civil Engineers, said that the organization has advocated for maintaining a redundant power source as part of a contingency plans when transmission lines are taken out of service for major upgrades.
Lynch is the energy representative for the American Society of Civil Engineers' Committee on America's Infrastructure. The group regularly issues a report card on the state of the nation's infrastructure, most recently this year.
During planned outages, an extra line can pick up the slack when demand unexpectedly peaks and reduce the risk of failure, Lynch said.
"If there is a third line it may not be needed everyday but if you have an outage on one of the lines that line can step up to the plate," Lynch said. "People always ask why we need to install new power lines and the answer is we need it for redundancy in case something happens and you need to repair lines."