The CMP's builder's risk insurance is expected to cover the fixes—even to the chiller plant, which was running but not yet turned over to the U.N. If the surge had hit two months later, the plant would not have been covered by insurance.

That's minor consolation to Keith Fitzpatrick, senior vice president of the prime consultant, local engineer Syska Hennessy Group, for the 952,000-sq-ft basement and the building infrastructure. He calls the chiller-plant flood "almost shocking and kind of heartbreaking."

The target month for finishing chiller repairs is May. During the work, the U.N. is moving critical long-lead items, such as variable-frequency drives, to a higher elevation, says Fitzpatrick.

Though the flood was a spectacular disruption, the "deviation" that had the greatest impact was a campus-wide security redesign in 2010, two years into the work. "Of all the disruptions, the eight to 10 months [lost] was the only punch in the stomach," says Champion. "It took a lot to keep everyone focused [during the work slowdown]," he adds.

The hardening, prompted by attacks on U.N. facilities elsewhere, is delaying completion by a year, until June 2014. Though the U.N. is mute on all details that might affect safety, the redesign includes enhanced perimeter security and structural reinforcement under the low-rise conference building, which extends over FDR Drive (see site plan, p. 31).

The renovation is the first sweeping overhaul since the U.N. compound—designed by an international team of architects that included Le Corbusier, Oscar Niemeyer and Wallace A. Harrison—was completed in 1952. The original complex, including city- and state-funded site improvements, cost about $100 million (ENR 10/9/1952 p. 26).

The current scheme is based on a 2001 master plan by Milan-based Renato Sarno Group. In addition to the basement and infrastructure work and the restoration of the 320,000-sq-ft conference building, the reconstruction includes the iconic 39-story Secretariat Building—an 840,000-sq-ft office tower in the shape of a Rice-A-Roni box—and the low-rise General Assembly Building, which encloses 308,000 sq ft.

Time had taken its toll on the buildings, especially the Secretariat's curtain wall (see sidebar, p. 33). Due to leaks, the 98-ft-dia tilting dome of the General Assembly Building had been tarped over for years. Building systems were outdated, and there were no fire sprinklers.

The goal is to restore the buildings to their original appearance and refurbish the contents. The Secretariat, however, is an exception. A gut renovation, substantially completed last year, included new open-plan office layouts. The curtain wall was replaced, not restored, though it looks like the original.

Work includes upgrading all building systems to current building, energy and life-safety codes, though the U.N. campus, which has extraterritoriality status, is not under the city's jurisdiction. The scope also includes asbestos removal.