The Port Authority of New York & New Jersey, along with their construction manager, Hill International Inc., faced a daunting and unprecedented task: To temporarily provide commuters with alternative transportation modes, while reconstructing the tunnels and building a permanent replacement for the lost station. This had to be done at a highly accelerated pace, and in the context of the terrorist attacks, the construction site became the world's largest crime scene.

The Port Authority started by using simplified designs that allowed them to order long-lead-time materials before the contractor was even hired. They then awarded a net-cost, fixed-fee construction contract to a team of three contractors, and worked with the contractors to design the project while construction was under way, eliminating the need for a lengthy design process. The strategy was so successful that the WTC station was up and running one month early, and the rest of the project was completed on time.

The Port Authority Trans-Hudson (PATH) train system, in operation since 1908, links Newark, Jersey City, and Hoboken in New Jersey with Lower Manhattan in New York. The system has four routes, two of which terminate at the World Trade Center. Prior to Sept. 11, 250,000 riders used the PATH system every day, 67,000 of them traveling from the original WTC station.

The collapse of the Twin Towers destroyed the PATH train station on the lowest level of the WTC site, 75 feet below grade. Two tunnels beneath the Hudson River were destroyed by flooding, leaving two miles of tunnel in need of immediate repair.

The attacks of Sept. 11 also shut down the Exchange Place Station, the first stop on the other side of the Hudson River in New Jersey. The mission was to restore service to Exchange Place Station by the summer of 2003, and to a new temporary WTC PATH Station by December 2003 at a total cost of $544 million, of which $460 million was for construction.

Unique Circumstances and Constraints

It was clear from the beginning that this project could not be managed in the standard way. The greatest challenge initially was the concurrent forensic investigation.

"They needed to clean the site up and recover the remains of all those people," says Jim Palmer, senior vice president and director of Hill International. "We did not want to interfere with that process."

The Port Authority owns the entire WTC site, but did not have control of it during the cleanup. It wasn't until June 2002, eight months after the attack, that the loss recovery part of the cleanup was declared complete, and reconstruction could begin there in earnest.

But there was a great deal to do in the meantime. The first priority was to accommodate the commuters who still needed to travel between New York and New Jersey. The loss of the WTC and Exchange Place stations increased ridership at other stops by as much as 110 percent. To alleviate that burden, the Port Authority helped establish additional ferry service across the Hudson River. Prior to Sept. 11, there were only two ferry routes, one terminal in Jersey City and another in Hoboken which both led to a single terminal just northwest of the WTC. The Port Authority added two new ferry stops in Lower Manhattan, and one in Jersey City, increasing ridership by 127 percent.

On Feb. 1, 2002, the Port Authority awarded a single contract—to rebuild the WTC and Exchange Place stations and the tunnels—to a joint venture of Yonkers Contracting Co., Inc., Tully Construction Co., and A.J. Pegno Construction Corporation. In March, they began working on reconstruction of the Hudson River tunnels and improvements at Exchange Place Station, which had been planned before Sept. 11.

Construction began first on Exchange Place to accommodate the rerouted commuters pouring into Jersey City on the train and new ferry lines. Exchange Place was a pass-through station with no opportunity for track crossovers or for use as a terminal, and without the capacity to accommodate trains longer than eight cars. With the reconstruction, the platforms were extended to accommodate 10-car trains, increasing capacity and ridership. The station was back on line in June 2003.

Tunneling Under the Hudson River

The Exchange Place phase of the project also included construction of 1,500 feet of new cross-over tunnels, which necessitated the excavation and removal of 10,000 cubic yards of rock 100 feet below street level. This proved to be a challenge.

The contractors originally intended to blast and drill their way through the rock, because that was the method most familiar to them. But the Port Authority, which was closely monitoring the production rate, determined that the work was moving along too slowly. They decided instead to use "road headers," a unique piece of mining equipment that looks like a tank outfitted with a long arm, at the end of which is a massive rotating grinding ball.

"We burned a lot of time getting the road headers up and running," concedes Palmer. "That was a real lesson we learned. Next time, I'd have my options laid out in advance."

The tunnels under the Hudson River were the next priority. They were so extensively damaged by floodwater and mud that they had to be gutted back to their original steel tube, removing the entire internal infrastructure, including more than 16 miles of just cables and wires.

Because of new technologies in track design, the system could not simply be replaced. The new tracks changed the profile of the trains inside the tunnel, where the clearances already were very tight. The change in profile necessitated modifications of the interface points between the tunnels and the stations at either end.

The sequence of construction inside the tunnels was developed in conjunction with the contractor.

"Normally with this kind of rehabilitation project, the contractor would locate the track first and base everything else on that," explains Palmer. "Our contractor wanted to locate everything first and lay the track last because he wanted to use rubber-tired equipment to bring in materials.

"We developed a high level of survey control and made a 'clearance jig' to make sure that once he had the track placed, the trains wouldn't hit anything."

The World Trade Center Station

The last project to begin construction was the new station at the WTC site. The Port Authority decided to invest $323 million to build a temporary station there, knowing that it would remain standing for less than 10 years. Their goal was to restore PATH service within 24 months to help resurrect the regional economy. Institutional issues, such as site design and permitting, would have added one or two years to the schedule if they had gone straight to construction of a permanent station. In addition, a permanent station designed without knowing the layout of the entire 16-acre site would certainly require significant reconfiguration as the site took shape, adding to the long-term cost, explains Palmer.

To meet the timetable, the temporary station was consciously under-designed, he says. They used a very basic open-frame steel structure and stay-in-place concrete forms for the floor, and they designed it as an open-air station to obviate the need to spend time designing and constructing environmental controls. The lack of architectural detail allowed them to bid the steel on a per-pound basis before they'd even finished the design, shortening the time it usually takes to receive the materials. In addition, all the conduit carrying the utilities and cabling is exposed, eliminating the design time needed to artfully bury it. Those strategies shaved one year off the construction schedule, says Palmer.

The first piece of steel was erected in late August 2002; in November 2003, one month ahead of schedule, the station was fully operational.

Both new stations—the temporary and the permanent— occupy essentially the same site as the original, with the same track configuration, in order to minimize the need for repeated redesign. The Port Authority plans to replace the temporary station with the permanent one in stages without interrupting service.

Creative Scheduling and Contracting

The Port Authority needed to compress the timetable for every aspect of the job, from budget authorization and contracting, to design and construction. First, they completed cost estimates very quickly to present a budget for approval. Budget authorization alone for a project this large can take a couple of years, says Palmer; the Port Authority completed the process in just four months.

Hiring three contractors under a single net-cost, fixed-fee construction contract (based on time and materials, plus a fixed fee for profit and overhead) also greatly simplified and accelerated the process, but it changed the way they typically do business.

"Normally, a net-cost contract will be converted to a lump-sum contract after 10 to 15 percent of the work is done," says Palmer. "We converted small parts of the contract, but very little, because there simply wasn't time.

"When we brought the contractors on board, all we had were preliminary designs," he continues. "We developed a contract packaging strategy by looking at how all this would be built, and then arrived at design packages that would support that strategy."

For example, they decided to use all rolled sections for the structural steel of the WTC Station, because it would not require time-consuming fabrication. They developed framing plans based on that, and went out to bid without a complete design.

The contractor also went out to bid on the electrical equipment for the electrified railroad without room layouts, although they knew the schematic layout and the capacity of the system.

"Designers are uncomfortable with that approach," says Palmer. "There is some cost risk, because you're not sure you're doing it in the most efficient way possible. There is some breakage risk if you get to a point where you realize (the equipment) doesn't work well and needs to be changed."

Solving and Preventing Problems

The key to the success of this project was communication, both in preventing problems and solving them, says Palmer. He held weekly meetings with the contractor, project managers, and, depending on the issue, sometimes the designers. ("Normally, you have construction meetings with a smaller group of people, and you rely on documentation to relay the information.")

"We defined everything on everybody's hot list to lay problems on the table," says Palmer. "Then we went back to solve the problems; immediately if there were emergencies."

Palmer knew from past experience that the complex communication system needed to run the trains can be problematic.

"These are fairly complicated systems," he says. "There are monitoring systems, and systems giving commands to the passengers, to the trains, to the people at the stations. There are data and voice communication systems, and they all have to interface with all the other systems."

This challenge often breeds contention among designers, engineers, and vendors, says Palmer. To avoid that, the design was done with a working group that included both designers and engineers. This prevented problems that can arise from inconsistencies in the drawings or in field installations.

"The designers needed to be flexible with their preferences, and the vendors were told that we'd make adjustments to the price if the design changed significantly," explains Palmer. "Normally there's a tremendous aversion to change orders, but by talking about it up front, we avoided penalties for change orders."

Palmer says he has tried in the past to get designers, engineers, and vendors to work together, but never to this extent.

"It's the right way to do it," he says. "The entire communication system was designed, fabricated, and installed without a problem."

The contractors also encountered unanticipated problems that had to be solved from the field. For example, much of the wiring around the tracks was laid out generally but not in detail before installation began. Different subcontractors from different disciplines install different parts. The cabling systems, and even the kinds of power supplying the electrical systems, vary.

"We set up task teams to locate different equipment to solve the contractor's confusion, and worked with the contractor to figure out the routing of the equipment," explains Palmer. "We didn't anticipate the need to do that."

The Work Continues

The Port Authority is in the process of designing a permanent station for the WTC site. Preliminary designs are complete, and final designs were due in March or April, even though the entire 16-acre site has not yet been designed.

"We'll have to make some assumptions about site design," says Palmer. "The site now is essentially a hole in the ground with trains running through it. There's a lot of pressure to get it functioning as an economic center."

Palmer said the lessons learned here can be applied to other large-scale construction projects, but the success of this one is partly attributable to the unique circumstances.

"I've done a lot of other projects that have a lot of intensity, and they have their own momentum that develops over time," he says. "What this one had was momentum and a sense of urgency from the beginning.

"Typically, as problems arise, one or both parties will shut down," continues Palmer. "Neither side did that here, and that was absolutely because of the circumstances. We had this common mission, and we backed down from our hard positions."

But the process itself is very applicable, says Palmer.

"Depending on your tolerance, mainly for the aesthetics of the project, you can use this staged design concept for any large-scale project."

By Lisa Wesel

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