Documenting the Changes to Santiago Calatrava’s WTC Building

Some good info from the NY Times about all of the changes that Santiago Calatrava has had to make to his plans for the World Trade Center Transportation Hub over the years as budgets were trimmed and deadlines were made, broken, and made again. Rare is it that you get to see the designs modified out in the open as we have with this ever-troubled project, so it’s interesting to see how things move in slow increments from the architect’s vision to the city budget’s vision. Still, Calatrava seems upbeat about the project and from the included quotes and renderings, it looks like it will remain a remarkable building once it’s finished (assuming it stays in its current state, which you probably shouldn’t bet on). Here’s a bit about one of the three big changes:

More recently, both the budgetary and scheduling cross hairs fell on the column-free expanse that Mr. Calatrava envisioned for the mezzanine, the central transitional space between the streets above and the PATH passenger platforms below. To create 150-foot clear spans, he had proposed using two enormous rigid trusses (called Vierendeel trusses), on either side of the mezzanine, to support the arched roof structure.

There was growing concern that such complex engineering would jeopardize the ability of the Port Authority to complete the mezzanine in time to turn over the rooftop to the memorial and guarantee that the plaza would be open by Sept. 11, 2011. Once again, Mayor Bloomberg seemed to lead the charge, at least publicly. “The PATH station’s design, including the underground hall, is too complicated to build and threatens to delay the memorial and the entire project,” he wrote in The Wall Street Journal last month. “It must be scaled back.”