WSDOT SR 99 Ventilation Buildings_main

WSDOT SR-99 North/South Portal Operations Buildings

As Acoustical subconsultant, Greenbusch was involved with preparation of the RFP technical requirements and preliminary design for the WSDOT SR 99 North/South Portal Operations Buildings that support WSDOT's SR 99 Tunnel. Scope elements include ventilation system, jet fans, maintenance fans, building mechanical systems, emergency generator sets, wall constructions, interior finishes, and sewage ejection systems.

Greenbusch also contributed to the mechanical and vertical transportation sections of the design-build performance specifications. Staff worked closely to integrate the mechanical system noise and vibration control with the HVAC bridging documents to ensure appropriate sound isolation.


Acoustical Design,
Mechanical Engineering


Seattle, WA


$3.2 billion (SR 99 Tunnel Project)


HNTB Corporation (SR 99 Tunnel Design Build)
NBBJ (Bridging Documents)

Delivery Method


Similar Experience

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