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Cover Story - July 2003

Reconstruction

Port Authority on Schedule with Restoration of PATH Service

By Dan Friedman

Before September 11, 2001 67,000 people a day used the PATH station under the World Trade Center, about 16,000 used it to travel between Jersey City and downtown Manhattan.

When the Twin Towers collapsed they crushed both the Cortlandt Street No. 1 No. 9 IRT subway and the PATH stations below. While the passengers in the one train that was in the station escaped before the buildings came down, a major transportation artery between New Jersey and New was severed.

"We lost the downtown station along with the World Trade Center," said Lou Menno, program director with the Port Authority of New York and New Jersey, which owns and operates the PATH system that runs from various points in New Jersey to Manhattan. Menno is now overseeing its reconstruction for the PA.

"The PATH tunnels between downtown and Exchange Place in Jersey City were flooded by broken water and sewer lines and by the enormous amounts of water used to put out the fire and the smoke. The water destroyed all the infrastructure within the tunnels beyond repair," he said.

The water backed up all the way to the platform level at Exchange Place, the station in Jersey City. "To protect the rest of the system should, God forbid, the slurry wall (at the WTC site) give way, we installed concrete plugs at the east end of the station," said Menno.

The tunnels remained flooded for 40 days and 40 nights.

Team Building

On December 13, 2001, the PA's board authorized $544 million to reconstruct the PATH station and tunnels - $300 million was for hard construction, the rest going for design, engineering and other costs.

"We knew what had to be done - at Exchange Place, in the tubes and at the World Trade Center site - we just didn't know all the details. So we came up with a dollar amount that we thought would cover all three." recalled Tom Groark, engineer of construction for the PATH lines. "We explained to contractors our understanding of the scope of the job and asked them to team up."

At the end of January 2002, the contract was awarded to a tri-venture consisting of Yonkers Contracting Co. Inc., Tully Construction Co. Inc. and A.J. Pegno Construction Co., with Yonkers functioning as the managing partner.

"When the Port Authority decided to go ahead with this project, because of the nature of the disaster and the international profile of the job, they wanted to insure that the best-qualified contractors were involved in the process," said John Kolaya, executive vice president with Yonkers. "It was their idea to pre-qualify a select number of heavy construction contractors in the New York City area.

"When you're looking at a project this massive, it's very difficult for any one contractor to mobilize the resources - the management, the workers, the subcontractors - by themselves. It takes an awful lot of firepower from your other operations to be able to do something like this. So the individual contractors who were pre-qualified gravitated toward teams. Two teams were ultimately formed."

Yonkers and Tully had a long history of working together. Most recently Yonkers worked as a subcontractor on Tully's sector of the World Trade Center site, supplying ironworkers to cut the down the twisted steel. Tully, at the time the contract was bid, was working with Pegno on the reconstruction of the No. 1 and No. 9 subway station. So the team made sense to all involved. Kolaya noted that both of the teams that formed were eminently qualified. At that point, it came down to price.

When the project started, no one knew exactly what they had gotten themselves into.
"We brought in the design and management group and began figuring out what had to be removed, what could be rehabilitated and what needed to be totally rebuilt," said Groark. "We created the plan as we went along."

"When you start with a completion date, but you don't have any plans, you have a real job on your hands," said Kolaya with a chuckle. "There was no prep time whatsoever; we had to start building immediately. In a typical design-build project there is usually about a year of design time that proceeds significant portions of the construction. Here we had to start work right away with just concepts and preliminary drawings."

What made it possible, said James Strobel, project manager for the tri-venture, was the willingness of the Port Authority to do away with traditional formalities, make quick decisions and get into the trenches with the contractors. A tangible sign of this commitment is fact that the PA's staff assigned to the project have taken offices in the same building as the tri-venture-115 Broadway, on the southeast corner of Ground Zero.

"Everybody involved in this really wants to be here," said Strobel. "Everybody feels part of the team, not just those in the tri-venture, but all the subcontractors and the Port Authority people-their construction management people, their design people, their consultants.

"The Port Authority is right here in the same building with us. If we have a problem, we run right upstairs, bang on the engineer's door and say, 'We've got a problem, let's solve it.' There's no time for letters, there's no time for formalities. They know the importance of the job and they want to get it done as quickly as is physically possible. The attitude around here is, 'Let's just make it happen.'"

The Right Tool for the Right Job

When the contract was awarded, the cleanup of Ground Zero was still underway and there was no way to reach the PATH station beneath it. So work began by removing the plugs at Exchange Place.

There had been talk for sometime of finding a way to connect the five PATH tunnels that run under Exchange Place, so that trains could change direction there. There was also a need to extend the platforms. The PATH now uses eight-car trains, but the platforms at Exchange Place could only accommodate seven. Before 9/11, the tentative plan had been to extend them by moving west into the river. With the station closed, it was not only safer, but also easier and cheaper, to extend the platforms to the west.

The building of the connecting tunnel began with the typical drill-blast method. But progress was painfully slow, both because of restrictions imposed by buildings above the station and because of the subtlety needed to connect five existing tunnels.
"This was not the typical case where drilling and blasting could knock it out without any thought," said Kolaya. "We found that there were angles and shapes and shaves an undercuts and overcuts, all kinds of geometry that didn't lend itself to drilling a bunch of holes and shooting it."

When it became obvious that the deadline would not be met using the drill-blast method, Jim Brady of the BU Corp., the project's tunnel consultant, suggested trying a roadheader, a machine used in coal mines. Roadheaders look like mechanical monsters with nub-like picks on their cutterheads that bite into rock, crush and pulverize it. The machines are equipped with gathering arms that collect the rock debris (called "spoil") and places it on a conveyer in the machine's center, which brings the spoil to a loading boom at the rear. From there it is collected and can be transported out of the tunnel.

"The first machines we brought in (from West Virginia) weren't large enough; they barely gave us the production we were getting out of the drill and blast," said Strobel. However, larger roadheaders, so big that they had be dismantled to fit into the existing tunnel and reassembled for the actual work, did the trick. "Eventually, when we got the right equipment down there, it quadrupled our production and allowed us to finish on schedule," he added.

"In that situation we had to stop on a dime and change our whole course, and the Port Authority was there with us 100 percent of the time," said Kolaya. "When we had to get a roadheader in, they'd stop their PATH operations, make available their work trains and their engine, and we'd get that roadheader in. They always treated this job as their number one priority. This is not a hard money job; we're all looking for end results."
In April 2003, the heavy construction was complete and the first test train was successfully brought in and out of Exchange Place. The station reopened for passenger traffic to Newark on June 29.


In the Muck

As they were rebuilding Exchange Place, the tri-venture was also advancing into the tunnels from the Jersey side.

"The shell of the tunnel was in good shape," reported Groark. "The Port Authority has checked them regularly for decades, so that wasn't a surprise. The tunnels were not structurally impacted by the attack, it was just the water that caused the damage."
Virtually everything in the tunnels had to be removed. "The tunnels were completely stripped of all the existing tracks, ballast, and ties," said Strobel. "We pulled out all the existing mechanical lines, the compressed air lines, fire lines, all the electrical utilities, all the signal cables and switches."

In the original design, the running rail was fastened to evenly spaced wooden cross ties that were embedded in a layer of stone gravel for stability. The reconstruction brings the tracks into the 21st Century. For the first time in the PATH system, direct fixation fasteners were used. The fasteners consist of a series of direct steel baseplates equipped with a rail seat and baseplate pad, side insulators, rail chips and threaded anchor bolts that are attached at even intervals to the rail and then bolted to a new concrete track bed. This approach eliminates the need for wooden cross ties or a ballast layer.

"The advantage of the direct fixation rail bed is that it doesn't shift," explained Menno. "You don't have to do realignment. It decreases the amount of maintenance and it provides a smoother ride."

The old terra cotta clay duct banks were hauled out and all new conduit was installed. "We got as much conduit into those tubes as we possibly could," said Kolaya. "There was a lot that won't be needed for quite a while, but this was the only opportunity we had to do it."

As with all tunnel jobs, one of the hardest aspects was access. When work in the tunnels began, on one side of the river they were building a new connecting tunnel and at the other Ground Zero was still being cleaned-up. When the final beam was removed from the WTC site on May 30, the PA had far more access the New York end of the tunnels. It also allowed work to begin on the new downtown station.

The Temporary Station

By far the largest part of the project is the design and construction of the new PATH terminal on the site of the WTC.

Those working on it refer to it as the "temporary station" because it is being conceived of as the first step in the construction of a Grand Central Terminal-like transportation hub for downtown. That hub will integrate the PATH and the New York City subway system, and, some advocate, will include new connections to the Long Island Rail Road as well.

The new temporary station is being built in the footprint of the old. It is, Strobel says, "almost an exact image of the station that was destroyed-five tracks, three platforms right where they were before, and all the operational space needed to run it."
"The whole station was demolished by the attack and so was removed," said Groark. "The only structural element that remained intact was the escalator hill, and a good part of that was used for the new escalators."

The major difference is that before 9/11, when commuters came to the top of the escalators they found themselves in the shopping concourse under the towers. The concourse is, of course, gone. A new means of reaching the street had to be designed.

In the new station, after the traveler reaches the top of the escalator, she or he will then ascend another set of stairs and walk east underneath the #1 and #9 station. The PATH station's exit will be on Church Street, near Fulton Street, where stairs will come up to street level under a soon-to-be constructed 120-ft. by 90-ft. canopy. There will also be, for the first time, a series of elevators to make the station ADA compliant.
"It's a simple low-key station," said Carla Banacci, program manager for the Port Authority's in-house design team. "The focus is on putting it back where it was and on functionality, on allowing safe and easy access and egress. "

It will be an open air-station. The sides of the station will be open with an opaque vinyl mesh to help screen the on-going construction on the site. On the inner walls that abut the slurry wall, there will be fiberglass panels with photographic images from the history of lower Manhattan and the PATH system. The station's steel beams and metal deck will all be exposed.

"The station will be left plain so that it's easily adaptable for the second, permanent station," said Banacci. "We're trying to give it an appropriate presence that reflects its temporary nature and leaves room for the future grand terminal."
In addition to the station itself, an entirely new substation had to be built to provide power to the trains. The transformers had to be manufactured and brought in from around the world on a fast track.

To meet the goal of having the station fully operational by November, crews are working, as they have from the beginning, 16-hours a day, six days a week.
And even as the completion of the temporary station nears, planning is going on for the next stage of reconstruction.

"We're determined to keep in step with Gov. (George) Pataki's timetable," concluded Menno. "We have the goal of the third or fourth quarter of 2006 for the permanent station. We're working closely with the Lower Manhattan Development Corp. and Silverstein Properties to finish the design this year and break ground early next year."


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