Take a stroll behind the arena today and you will catch a glimpse of an immense two-block-long construction site – an active work zone located in a 30-foot-deep chasm stretching between Atlantic Avenue and Pacific Street. The site will soon be the home of an important storage and service rail yard for MTA’s Long Island Rail Road (LIRR) trains. It will replace Vanderbilt Yard, which was used for off-peak daytime storage and inspection of electric trains on the LIRR’s Atlantic Branch.

The new rail yard is part of a 22-acre mixed-use development project in the Prospect Heights neighborhood of downtown Brooklyn called Pacific Park, a mixed-use commercial and residential development project that will include 17 buildings when completed. The developer is Greenland Forest City Partners – a joint venture between Forest City Ratner and Greenland USA.

WSP USA’s transportation and buildings teams are working together on the Pacific Park project. But collaboration between the two businesses actually began prior to WSP’s 2014 acquisition of Parsons Brinckerhoff, when both firms were independently selected to join the project – WSP on the buildings side and Parsons Brinckerhoff on the transportation side.

On the transportation project, WSP is responsible for full rail yard design, including civil, structural, mechanical and electrical engineering.

“We are providing the Long Island Rail Road with a new rail yard,” said Sean O’Gorman, project manager for WSP. “We are designing a new power system, new tracks, maintenance building, a new staff building and several other upgrades and improvements.”

WSP is also responsible for architectural design; signal system design, including signal layout, route and aspect charts; circuit design, signal cable and conduit layout; lighting, drainage and utility relocation; and preparation of plans and specifications.

WSP’s involvement with the revitalization project began with a role in the construction of the Barclays Center, an 18,000-seat sports and entertainment arena located at the northern edge of the Pacific Park project, which has served as the home of the Brooklyn Nets professional basketball team since 2012 and the New York Islanders professional hockey team since 2015.

WSP was the mechanical/electrical/plumbing engineer for the arena project, preparing significant features that included demand-controlled ventilation, a 1,500-kilowatt life safety generator, underground storm water storage tanks and low flow plumbing fixtures. The arena has been certified LEED Silver by the U.S. Green Building Council.

The mechanical system includes a 2,700-ton electric chiller plant and a large boiler plant. The air distribution system includes four major air handing units connected by a continuous loop duct at the top of the arena.

High-efficiency, gas-fired heaters provide hot water for the entire arena including showers, kitchens and hydrotherapy equipment. The hot water is delivered through a centralized system to ensure availability at all times.

An air-side economizer provides free cooling for the majority of the year, with heat recovery systems to pre-heat and pre-cool the vast amount of outside air required for ventilation. The climate control system is further aided by a roof constructed out of 135,000 square feet of grass tiles, which creates a green landscape within the urban setting, acts as a natural air conditioner, absorbs rainwater to lessen the strain on the city’s sewer system, and creates a natural sound barrier.

It was during the arena’s design stage in 2005 when plans for the rail yard emerged.

Forest City Ratner Companies preferred to construct the stadium at the corner of Atlantic Avenue and Flatbush Avenue, but the desired location interfered with the LIRR’s century-old Vanderbilt Yard.

To keep the arena plans on track, an offer was made to LIRR: Move the rail yard to a temporary location to accommodate the arena plan, and in exchange, the developer would finance and build a modern rail yard to replace the outdated Vanderbilt Yard.

“The reconfigured rail yard plan was essential so that the client could progress with the overbuild vision,” O’Gorman said. “Vanderbilt Yard had been updated over many decades, with new structures built over old ones. That has made it a somewhat complicated infrastructure that was in critical need of an overhaul to bring everything up to date.”

LIRR accepted the offer.

In 2006, prior to the formation of the Greenland Forest City Partners joint venture, Forest City Ratner Companies engaged WSP to complete a study on the best approach for moving Vanderbilt Yard. The firm developed alternate rail yard design concepts as well as modifications to its layout, retaining walls, foundation structures and facility buildings.

In order to maintain train service without interruption during construction, a three-staged construction plan was developed. A temporary yard was created in 2009 to replace the aged Vanderbilt Yard and expedite construction on the Barclays Center. A temporary railroad trestle was also built and a number of temporary switches were installed to facilitate construction.

Once the Barclays Center neared completion, work could begin on the new Vanderbilt Yard.

“With a new rail yard, LIRR is not only gaining additional capacity, but it’s going to remove what has been an ongoing maintenance challenge and replace it with a completely new rail yard,” O’Gorman said.

Vanderbilt Yard will serve as a parking area for LIRR trains not needed during off-peak hours. The reconfigured yard will include seven storage tracks and two connections to the LIRR Atlantic Branch main line. Plans include ventilation facilities, an employee headquarters, new traction power and facility power substations, a DC breaker house and signal power motor generator.

The project also includes a new tunnel portal connecting the mainline LIRR tunnel to the nearby Atlantic Terminal, the largest transportation hub in Brooklyn, which serves LIRR and nine subway lines.

“Designing a modern railway by shoehorning services in and around an existing tunnel from 100 years ago was not practical,” O’Gorman said. “The current tunnel is basically not big enough. Trains are bigger, and a lot more services are required. The old tunnels weren’t designed to handle the size and volume of these trains.”

The resulting alignment between Vanderbilt Yard and the LIRR tracks will be more direct, shaving several minutes of time transferring trains to-and-from the exchange with the rail yard.

“It will allow the trains to directly enter the terminal and access more platforms at the terminal in the west portal connection,” O’Gorman said. “Before, the trains had to back up, and then pull into the yard.”

Tohandle storm water and sewage, the design included below-track storm water detention, underground infiltration beds, a 22,000-gallon storage tank and a quadraplex pumping system. The system will connect to the city’s sewer system and provide 100-year protection from flooding.

When Libby Engel walks around the Pacific Park construction site, she takes great pride in identifying and explaining some of the concrete fixtures interspersed throughout the area.

Engel, the deputy project manager of WSP’s transportation-related work at the site, has been focusing on Pacific Park since she joined the firm more than four years ago. She spends most of her time working on aspects of the project that few people will ever see, but she remains motivated knowing that she is playing a key role on a project that will make a profound impact on the Prospect Heights neighborhood.

“This has been a unique opportunity, creating something new in an urbanized area,” Engel said. “How often do you get a chance to work on a project that is literally creating a new neighborhood?”

The concrete foundations, which are being designed by the firm’s buildings practice, will not only one day support an entire city block, but will also help streamline the spaghetti-like utility wires and cables that meandered through the old rail yard with little cohesion. It was a complex network that grew more convoluted over time, as new cables replaced old ones left behind, while the emergence of new technologies introduced wiring never anticipated by the original rail yard designers.

With the functionality of the rail yard depending upon the services those cables provide, there is little room for error or outages when re-routing and replacing the originals.

“Because of the complexity of coordinating the underground utilities and foundations, this is not a two-dimensional job,” Engel said. “We didn’t know what we would find in those tunnels, as there was not a lot of documentation. Fortunately, we had a way to create three-dimensional (3D) models of the areas where we were working.”

The 3D modeling turned out to be even more crucial to the success of the project than they initially realized.

“We found a number of conduits we weren’t expecting, and we were able to identify specific locations where we could safely put equipment,” Engel said. “It gave us a certainty of design that greatly minimized the impact of field conditions on our approach to the project.”

There was initially some reluctance to using 3D modeling on this project due to its seemingly high cost. But once its value was reinforced, and the long-term time and cost savings for this project were identified and explained, the client welcomed the new technology.

“3D modeling may not be applicable to all projects, but in constricted spaces it is really valuable,” Engel said. “Realistically, we couldn’t have created the Vanderbilt Yard design that we did without it.”

After the rail yard is completed and operational, work will begin on the third phase of the project – a new structural deck above the reconstructed rail yard that will become the face of the Pacific Park neighborhood, formerly known as the Atlantic Yards development.

“Once Vanderbilt Yard is operational, the structural platform can start going up,” said Yefim Gurevich, project manager for WSP’s buildings-related work on the project, including the platform and its foundation. Design work is already well under way for this phase, and the firm is providing full-service civil, structural and mechanical engineering.

While the specific configuration of the high-rise residential buildings remains to be finalized, the platform and foundation structure is being designed with load parameters in mind that match the developer’s vision for Pacific Park, and provide plenty of options for the new neighborhood.

“We do know that there will be six buildings, and the maximum dimensions have been determined for the buildings, which will range from 16 to 50 floors in height,” Gurevich said. “While there might be some commercial properties on the ground level, these will all be residential buildings.”

Gurevich, who has been involved with the project for more than eight years, said one of the challenges was the limited amount of space available for the foundation.

“Between the tracks and the utilities, we had to be very cautious with how we developed the piles, casings and platforms,” he said. The supporting platform, which transfers the loads, will be made out of structural steel.

While incorporating an urban residential community with a rail yard has been accomplished before – such as with Manhattan’s Hudson Yards project – Gurevich said the Pacific Park project is unlike anything he’s seen before.

“It’s a novel approach for New York City,” he said. “Placing the foundation between the tracks, without knowing the exact shape of the buildings, makes it rather unique.”

Collaboration among the designers, the client, and the LIRR has been essential in the project’s success thus far.

“Considering the scope of this project, and the overlapping of the many different trades, communication and collaboration has been a critical element every step of the way,” he said. “We always consider the concerns of other stakeholders involved with the project, and in the end, that collaborative mindset has made this a successful project so far.”

The consensus among the people involved with Pacific Park is that it has been a challenging, rewarding and career-defining project.

“In spite of the numerous changes and challenges presented by the project over the years, it has been very exciting,” Gurevich said. “Finding solutions that satisfy everyone is never easy, so to see it all come to fruition after being designed and redesigned so many times is satisfying. It has been a fantastic experience to see this unfold before my eyes.”

“Long term, this project has the potential to change the face of Brooklyn,” O’Gorman added. “We are in the process of removing a large hole that separates a neighborhood, replacing it with affordable housing and creating opportunities for the community.” He said it has been “a pleasant experience” working with people on a complex project who are focused on the same goal.

“When it’s done, most people aren’t going to know about the bits that we did,” O’Gorman continued. “But that’s OK. We will all take great pride in knowing that what we are doing here today is enabling something great to happen in Brooklyn. There will never be anything quite like this.”