Manhattan Transfer

31 January 2007 (Last Updated January 31st, 2007 18:30)

Like the rest of the World Trade Center complex, the WTC Transportation Hub carries a huge burden of responsibility. Santiago Calatrava's design offers an imaginative solution: a structure shaped like a bird in flight that will have symbolic resonance for millions of New Yorkers while serving 80,000 passengers a day. Jim Banks reports.

Manhattan Transfer

Ever since 9/11, it has been clear that whatever structures came to stand on the World Trade Center site would serve a symbolic purpose greater than any other building project of the 21st century. The site has become a focal point for a nation, and
the aesthetic value of every structure on the site will be just as important as its functional qualities.

The WTC Transportation Hub is a crucial element of the masterplan, both functionally and aesthetically, and its reconstruction is a top priority.

It requires the construction of a Port Authority Trans-Hudson (PATH) terminal serving over 80,000
passengers every day, and will interconnect and extend pedestrian access to PATH, ferries and subway lines across Lower Manhattan.

The design for the $2bn project, by internationally renowned Spanish architect and engineer Santiago Calatrava, makes greater use of open space in the Wedge of Light Plaza and provides additional access from two major streets. State-of-the-art safety,
security and environmental enhancements are other vital ingredients.

Calatrava's understanding of complex function and aesthetic form makes him an ideal choice for the WTC Hub, and he is fully aware of its significance: "I feel a profound sense of responsibility, rather than any pressure. The memories, the sorrows and
the hopes of a great many people are intrinsic to this project. Like everyone else involved in the World Trade Center Transportation Hub, I want to do my utmost to honour these feelings."

A PLACE IN HISTORY

The WTC PATH station originally opened as the Hudson Terminal in 1909, which was demolished to make way for the WTC towers and reopened in 1971 as the terminus for the Newark-World Trade Center and Hoboken-World Trade Center routes. This was destroyed
during the September 11 attacks and a temporary station has served the site since 2003.

The design reflects Calatrava's artistic and architectural influences, the practicalities of handling a growing number of multi-modal passengers and the spirit of the overall plan for the site.

"Notoriously impatient, native New Yorkers can hardly wait to see the finished article."

"Daniel Libeskind's masterplan has tried to give a soul to the buildings that will be constructed on the site," explains Calatrava.

"It was a challenge to work within this masterplan and make the most of its aspirations. The key decision in
balancing symbolic power with function was to conceive the building at street level as a freestanding structure, angled to sit along the southern edge of the Wedge of Light described in the masterplan.

"Rather than being connected to another structure, as was originally proposed, the Transportation Hub now occupies its own landscaped plaza. This treatment of the site creates a quieter space – a kind of pause – amid the dense network of
buildings planned for Ground Zero. It also creates a link in a procession of green spaces, extending down Park Row from City Hall Park to the churchyard of St Paul's, then through the WTC Transportation Hub plaza to the Memorial Garden."

This quieter space must also contain a complex transport solution, and, working to Calatrava's original design, the Downtown Design Partnership, led by DMJM+Harris and STV Group, had to seamlessly connect the PATH to the subway system or the site
above ground. A possible connection to the Long Island Railroad is also being considered.

"In any station serving different modes of transport, it is critical to provide clear, coherent circulation within the terminal," observes Calatrava. "Because of the programme established for the station, the circulation was necessarily vertical.
Passengers have to be brought down to the various train levels or up to the street as efficiently as possible through a system of escalators, elevators and stairs.

"The biggest challenge is to give dignity to these spaces, even when they are far below street level. This is one of the reasons why light is so important within the building, and why we tried to create clear-span spaces that would feel very
open."

MEMORIAL OF LIGHT

The freestanding grand pavilion rests on ribbed arches reminiscent of a cathedral, and the roof can open to provide ventilation and natural air conditioning. The key to the structure is light, which plays both a functional and a symbolic role.
Inspired by the old Penn Station and Grand Central Terminal in New York, the design allows natural light to penetrate to platforms 60ft below street level.

However, Calatrava cites a symbolic gesture as the defining idea of his design: "When I was making my initial sketches, I drew an image of a child opening her hands to release a dove into the air. This gesture was my main inspiration.

"The biggest challenge is to give dignity to these spaces, even when they are far below street level."

"Light is a structural element of the building – one could say the building is supported by columns of light. Light floods through the roof structure into a column-free space and then filters all the way down to the train platforms through the
glass-block floors."

Calatrava's design has been well received and the Hub's 2009 completion date is eagerly anticipated. "Right from the start, the public's response has been an integral factor in the construction of this project," he observes. "The warmth of the
response has encouraged everyone involved in this effort."

Succeeding as both vital transport link and iconic building, Calatrava's design fulfils both the letter and the spirit of the masterplan. Notoriously impatient, native New Yorkers can hardly wait to see the finished article.