Satellite Transit System Controls Project
Amendment Authorization (CIP #801043)
Item No. 8g_supp
Meeting Date: November 17, 2026
Purpose & Scope
Project Purpose: Life Cycle Extension project of the STS’s Control System to include the
replacement of obsolete software, hardware, radios and associated components.
Fiber Optic Loop /
Electrical Construction
Phase 1- Construction
Automatic
Train Control
System
- Software
- Hardware
- Network
- Radios
- Certification
21 Cars
Phase 2 - Equipment
Project Scope:
2
Operational Impacts
• Nightly STS Shutdowns
• North Loop from 12AM to 6AM
• South Loop from 11PM to 5AM
• Shuttle Track from 10PM to 6AM
• Active Construction and Operational
Readiness (COR) plan
• Busing / Wayfinding
• NSAT: D Annex ground board to Gate
N13î´²
• SSAT: B20 hardstand gates to Gate S1A
• Limited STS car availability during transition
from existing to new system.
DA
N13
B20
S1A
3
Current Budget: $78,240,000
This Request: $4,700,000
Revised Budget: $82,940,000
The request supports the Port’s
obligations for construction
completion and closeout
The project is funded by the
Airport Development Fund
Schedule Milestones:
• Construction Auth: Q3, 2021
• South Loop In Use: Q2, 2027
• North Loop in Use: Q1, 2028
• Substantial Completion: Q3, 2028
Schedule extended by 31 months
due to a construction contractor
defaulting and additional
manufacturing delays.
Project Budget and Schedule
4
5
1.8 Miles of Conduit
Maintenance Bays
Temporary Controls Center
New Controls Equipment
Project Photos
Project Photos
6
Old Vehicle Coupler
Replacement Vehicle Coupler
Vehicle Dynamic Testing
Vehicle Retrofit Work
Communications Retrofit
Temporary Controls Center
Action Requested
7
Request Commission authorization for the Executive Director to:
(1) Increase the Capital Improvement project budget and
authorization for the STS Controls Renewal and Upgrade project
(CIP#801043) at Seattle-Tacoma International Airport (SEA) by
$4,700,000;
(2) Execute related project change orders, amendments, work
authorizations, purchases, contracts and other actions necessary
in support of the project.
The amount of this request is $4,700,000 for a revised total
estimated project cost not to exceed $82,940,000.
Questions?
8
