South Terminal Expansion, Sea-Tac International Airport, SeaTac, WA
The South Terminal Expansion project enabled the Port of Seattle to meet its growing passenger load while strengthening safety and enhancing the passenger experience. The project expanded Concourse A and the Main Terminal, added a five-story Office Tower, and created a Combined Communications and Control Center. The previous concourse, which had seven gates, was replaced with a new terminal four times the size. It has 14 gates, moving walkways, four retail stores, nine food concessions, and airline offices. The highlight of the new terminal is an Arrivals Hall with a 70-foot high ceiling and large windows overlooking Mount Rainier.
Wood Harbinger provided the mechanical/electrical design and construction administration for this project except for the Office Tower mechanical design which was provided by an MBE firm. The expansion of Concourse A includes over 437,000 SF. The entire project encompasses 880,000 SF of interior space.
The HVAC system is a variable air volume system consisting of built-up air handling units with fan powered terminal boxes. Cooling is provided by connection to the central plant chilled water system. The hydronic heating water system uses steam from the central plant that has been converted to water.
Primary electrical services are from the 12.5 kV distribution system. Emergency power for the Terminal, Concourse, and Office Tower is provided by a 1500 kW standby generator.
A 400 Hz aircraft “ground power” system is provided using rotary generators and a central distribution system.
Electrical systems include primary power, normal and emergency distributed power, exterior and interior lighting, site lighting, fire alarm, and provisions for retail tenant improvements.