John Wayne Airport�s massive improvement project � a $543-million effort representing one of the largest public works programs in Orange County history -- is scheduled for completion by December 2011.

Pasadena-based Parsons Corp. is overseeing all three elements of the project, including construction of a 282,000-sq-ft, three-level terminal (Terminal C); construction of a 725,000-sq-ft replacement parking structure (Parking Structure C); and a 14,600-sq-ft central utility plant.

The first significant improvement project at the airport in 20 years will help the airport handle a scheduled passenger increase from its present 9 million annually to 10.8 million by 2011.

Work began on Terminal C in August 2009, with Arcadis (formerly known as PinnacleOne) of Irvine as construction manager and McCarthy Building Cos. of Newport Beach as general contractor.

�We�re right in the middle of structural steel erection,� says McCarthy project director Khatchig Tchapadarian. �The foundations are complete.�

�We can�t impact ongoing airport operations at all, so there�s a lot of work that we do that takes place at night, coordinated sometimes hour by hour. Work takes place from 11 p.m. to 5 a.m. If we have to do something in the terminal or airfield, there�s a concerted effort among all parties involved � operations, maintenance, TSA, subcontractors, etc. � to make sure that, by 5 a.m., we have everything put back together.�

Terminal C will be immediately south of and connected to the existing Terminal B. It includes six new commercial passenger gates, security screening checkpoints, three baggage carousels and passenger hold rooms (seating areas specific to a gate) at the north and south ends of the terminal. Two of the passenger gates will be modified to allow U.S. Customs and Border Protection employees to process international travelers.

Gensler of Newport Beach is the project architect and design director David Loyola says the selection of his firm for the job was a natural evolution because Gensler was the original designer of the airport�s main facility: the Thomas F. Riley Terminal.

�From the very beginning, it was clear that the new terminal would not look like an addition,� Loyola says. �The connector pieces would look a little different, but the major forms would be consistent with the original building. The color palette is very consistent. It�s somewhat neutral in that it has a timeless feel and allows the concessions to add more color.�

Designing the concession area involved considerable coordination with the airport, which chooses which vendors set up shop in the facility through an elaborate consulting and bidding process, Loyola says.

�[John Wayne] had a concession consultant on the team who helped the airport decide how much concession space should be included and what kind of concessions it should have,� he says.