S. 188

th

Street Tunnel

Project Authorization

Item No.

8g_supp

Date of Meeting June 27, 2023

Project Location

2

East Portal

Taxiway A/B

Runway 34R

West Portal

Control Building

Ventilation Ducts

Shared Port/City of SeaTac facility

Tunnel Scope Items:

• Structural (crack sealing/spall repair)

• Civil (signage)

• Electrical (lighting, power, emergency

power)

• Mechanical (ventilation, fire suppression)

• Communication and Special Systems (fire

detection/alarm, carbon monoxide

monitoring, security, egress/traffic

management)

Project Scope

3

Existing Facility Conditions

4

Egress Doorway Fire Alarm Station Walkway Fire Hydrant

Project Budget:

• Previous Budget: $24,500,000

• Revised Budget: $34,500,000

Budget increase due to complete

ventilation redesign and higher

than anticipated escalation costs

Additional Airline MII approval not

required

Project Schedule:

• Construction Start Q4 2023

• In-Use Date Q4 2024

Project Budget and Schedule

5

We are here

Cone of Certainty