Template revised January 10, 2019.
COMMISSION
AGENDA MEMORANDUM
Item No.
8g
ACTION ITEM
Date of Meeting
November 17, 2026
DATE: November 5, 2026
TO: Stephen P. Metruck, Executive Director
FROM: Keri Stephens, Director Aviation Facilities and Capital Programs
Eileen Francisco, Director Aviation Project Management
SUBJECT: Satellite Transit System (STS) Controls Project Amendment Authorization
(CIP #801043)
Amount of this request:
$ 4,700,000
Total estimated project cost:
$ 82,940,000
ACTION REQUESTED
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; and (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.
EXECUTIVE SUMMARY
The STS Controls Project is in the process of replacing critical airport infrastructure to keep the
airport train system operational for the next 10 to 15 years. The STS transports passengers to and
from the Airport’s North and South Satellites. This project is a renewal and replacement of the
STS’s Automated Train Control (ATC) system. The current ATC system is 26 years old and is at the
end of its useful life. This project installs STS network infrastructure, replaces end of life ATC
systems equipment, and updates the ATC with the most current version of the manufacturer’s
controls software while maintaining passenger service to the Satellites.
Significant project delays resulted from the insolvency of a key network infrastructure contractor,
necessitating the exercise of the construction contract surety. In addition, the manufacturer is
forecasting a significant delay in final delivery and certification of the ATC system. The Port
expects to assess liquidated damages for time beyond the ATC contract completion date but does
not expect the compensation to be available for use during the remaining installation and
certification periods. This request provides the necessary funding for the Port to execute
amendments extending the Project Specific Consultant contracts.
COMMISSION AGENDA – Action Item No. 8g Page 2 of 5
Meeting Date: November 17, 2026
Template revised June 27, 2019 (Diversity in Contracting).
JUSTIFICATION
This project provides important benefits for continued airport operations, security, and safety.
The STS is the primary conveyance method to move passengers between the Main Terminal and
the combined thirty-five gates in the North and South Satellites. In 2025 the STS carried
approximately 30 million passengers. The last major STS upgrade was completed in 2003 under
CIP #100783. The current ATC subsystem was installed around 2001, and major components are
now either obsolete or at the end of their useful life. The ATC system is an integrated set of
computerized hardware, software, and networks that safely operate the automatic movements
of the train system. The STS will cease to operate without a functioning ATC. Action is required
now to ensure the STS remains operational before more critical pieces of the ATC become
obsolete or irreparable. A catastrophic failure or even a prolonged failure of the STS would
significantly impact operations at the Airport.
At the forecasted rate of use, the STS will reach the end of its expected useful life around 2032;
with additional comprehensive renovation, renewal, and replacement expenditures the STS
subsystems life may be extended. Under CIP C801377, Port staff are producing a Project
Definition Document (PDD) for the eventual replacement program.
Diversity in Contracting
The project team with the Diversity in Contracting Department determined a Women and
Minority Business Enterprise (WMBE) participation aspirational goal of six percent (6%) for the
Automated People Mover (APM) Consultant contract, which has achieved a 13.7% WMBE
participation rate. Approving this request will authorize additional funds for the APM Consultant
and will not impact their goal.
DETAILS
This project installs modern and redundant fiber optic and radio networks; replaces end-of-life
ATC systems hardware and upgrades the ATC system to the manufacturer’s latest controls
software version, all while maintaining passenger service to the North and South Satellites. The
project is divided into two distinct phases.
Scope of Work
Phase 1 – Design and construction of a new hardened STS controls fiber optic network including
conduit, fiber optic cable, server rooms, and supporting electrical infrastructure. This work is
complete.
Phase 2 – Design, installation, testing and certification of a new STS train controls system
including new ATC software and associated equipment (hardware, servers, computers, radios,
networking equipment), STS Vehicle ATC replacement, system testing, certification and
decommissioning of the old system.
COMMISSION AGENDA – Action Item No. 8g Page 3 of 5
Meeting Date: November 17, 2026
Template revised June 27, 2019 (Diversity in Contracting).
Both phases require over-the-ramp busing and passenger wayfinding support.
Schedule
The project experienced a 12-month delay when a key contractor became insolvent. In addition,
the manufacturer is forecasting a 31-month installation delay.
Activity
South Loop In-use date
North Loop In-use date
Substantial Completion
Cost Breakdown
This Request
Total Project
Design
$0
$9,000,000
Construction
$0
$7,740,000
Equipment Procurement
$4,700,000
$63,200,000
Support Services
$0
$3,000,000
Total
$4,700,000
$82,940,000
ALTERNATIVES AND IMPLICATIONS CONSIDERED
Alternative 1 – Reduce Scope of Contracted Support
Cost Implications: $0
Pros:
(1) No additional authority required.
Cons:
(1) Loss of specialized technical expertise, equipment, and installation oversight.
This is not the recommended alternative.
Alternative 2 – Provide additional funding authority for support through completion.
Cost Implications: $4,700,000.
Pros:
(1) Allows the Port’s technical experts to continue working on the project without a gap in
coverage.
Cons:
(1) Additional capital expenditure.
This is the recommended alternative.
COMMISSION AGENDA – Action Item No. 8g Page 4 of 5
Meeting Date: November 17, 2026
Template revised June 27, 2019 (Diversity in Contracting).
FINANCIAL IMPLICATIONS
The project expects liquidated damages returned to the Port; however, the amounts will not be
determined until the project is completed. The risk of an additional funding need was highlighted
in the July 9, 2024, Commission action.
Cost Estimate/Authorization Summary
Capital
Expense
Total
COST ESTIMATE
Original estimate
$57,000,000
$0
57,000,000
Previous changes – net
$21,240,000
$0
$21,240,000
Current change
$4,700,000
$0
$4,700,000
Revised estimate
$82,940,000
$0
$82,940,000
AUTHORIZATION
Previous authorizations
$78,240,000
$0
$78,240,000
Current request for authorization
$4,700,000
$0
$4,700,000
Total authorizations, including this request
$82,940,000
$0
$82,940,000
Remaining amount to be authorized
$0
$0
$0
Annual Budget Status and Source of Funds
This project, CIP C801043, was included in the 2026-2030 capital budget and plan of finance with
a budget of $78,240,000. A budget increase of $4,700,000 was transferred from the Aeronautical
Reserve CIP (C800753) resulting in zero net change to the Aviation capital budget. The funding
source will be revenue bonds. This project was approved as a Majority-in-Interest by the airlines
on May 26, 2020.
Financial Analysis and Summary
Project cost for analysis
$82,940,000
Business Unit (BU)
Terminal Building
Effect on business performance
(NOI after depreciation)
NOI after depreciation will increase due to inclusion of
capital (and operating) costs in airline rate base.
IRR/NPV (if relevant)
N/A
CPE Impact
$0.20 in 2029
Future Revenues and Expenses (Total cost of ownership)
Additional Aviation Maintenance personnel are required to support the installation of the ATC
system and expanded operation of two to three trains in a loop. Staff will evaluate further staffing
increases for the expanded loop capacity as operations dictate.
ATTACHMENTS TO THIS REQUEST
(1) Presentation slides
COMMISSION AGENDA – Action Item No. 8g Page 5 of 5
Meeting Date: November 17, 2026
Template revised June 27, 2019 (Diversity in Contracting).
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS
July 09, 2024 – The Commission authorized the Executive Director to execute project related
change orders and amendments. The total authorization was $78,240,000.
July 27, 2021 – The Commission authorized the award of a contract with the STS Manufacture,
advertisement and award of a construction contract and of contracts for busing and
wayfinding support. The total authorization was $78,240,000.
July 14, 2020 –The Commission authorized the award of a consultant contract, design,
preparation of construction and purchasing documents, and use of Port crews. At that
time, the estimated project cost range was $65,000,000 to $95,000,000.