COMMISSION 
AGENDA MEMORANDUM                        Item No.          8g 
ACTION ITEM                            Date of Meeting      October 24, 2023 

DATE:     October 12, 2023 
TO:        Stephen P. Metruck, Executive Director 
FROM:    Keri Stephens, Director, Aviation Facilities and Capital Programs 
Eileen Francisco, Director, Aviation Project Management 
SUBJECT:  PLB Renewal & Replacement Phase 4 (CIP# 801308) – Design & Construction
Authorization 
Amount of this request:              $16,850,000 
Total estimated project cost:         $17,000,000 
ACTION REQUESTED 
Request Commission authorization for the Executive Director to (1) Prepare design and
construction bid documents for the Passenger Loading Bridge (PLB) Renewal Replacement Phase
4 project; (2) Purchase six PLBs and associated gate equipment for specified gates; (3) Use Port
of Seattle crews, and small and major works on-call contracts to support design activities and to
perform the construction work; and (4) Advertise, bid, and execute up to four major works
construction projects. The amount of this request is $16,850,000 for an estimated total project
cost not to exceed $17,000,000. 

EXECUTIVE SUMMARY 
This project will replace the next set of six (6) passenger loading bridges that are at the end of
their functional service. This project will remove the existing PLBs, including columns, and install
new aspects that will bring the systems up to current design standards. The foundations for each
PLB column will also be modified/replaced to comply with the current seismic code. To improve
the customer experience, acrylic coating paint will be applied to up to two of the new PLBs to
evaluate the thermal effect in hot weather scenarios. The existing ancillary equipment will be
removed and reinstalled as-is. 
JUSTIFICATION 
Seattle-Tacoma International Airport (SEA) is among the busiest airports in the United States with
over approximately 46 million passengers processed yearly (2022). In 2022, each PLB serviced
approximately 520,000 passengers including loading and unloading operations. In July of 2023,

Template revised January 10, 2019.

             COMMISSION AGENDA – Action Item No. 8g                                   Page 2 of 5 
Meeting Date: October 24, 2023 
we observed a single day record of approximately 198,000 passengers travelling through SEA,
illustrating the regional growth and importance of airport facilities. Reliable, well-operating PLBs 
are critical to airline and airport operations. With an expected service life of approximately 25
years, replacing these PLBs at the appropriate time is important in maintaining smooth airport
operations. Any unplanned gate outages, due to PLB or fixed walkway failure, impacts the
airports’ ability to properly process the growing number of passengers that are travelling through
SEA. 
Due to the extended manufacturing time for PLBs, maintaining a phased schedule is critical for
reducing the gate outage time during replacement. The work for this project will replace existing
assets that are highly utilized by customers and employees as they travel through the airport.
Disruption to the bridge operations have direct impact to airport-wide operations. 
Diversity in Contracting 
The design services will be completed using an existing IDIQ contract that was established in 2020 
which has a 24% WMBE participation utilization requirement.
DETAILS 
Scope of Work 
(1) Replacement of a total of six (6) PLBs, support columns, rotunda columns, and associated
control boxes. PLBs to be replaced for this project: 
• A1 
• A2 
• A3 
• A4 
• A5 
• A14 
(2) Modify existing column foundations, where applicable, to meet current seismic code
requirements. 
(3) Installation of bridge telecommunication connections to the MDC or COM room. 
(4) Install new 400Hz gate boxes for Gates A1, A2, A5, and A14. 
(5) Reconnect hydronics and electrical power to bridge systems. 
(6) Regulated Materials Management (RMM) – Coordination and containment. 
(7) Disconnect and reinstall existing equipment if necessary or required, which includes PC
Air Units (install isolation valves, if necessary), Potable Water Cabinet (PWC), and charging
equipment for electric servicing vehicles. 
(8) Apply Acrylic Coating Paint on exterior of up to two (2) PLBs to evaluate effect on thermal
properties. This was originally created as standalone project (C801323) but will be merged
with this project. 


Template revised June 27, 2019 (Diversity in Contracting).

             COMMISSION AGENDA – Action Item No. 8g                                   Page 3 of 5 
Meeting Date: October 24, 2023 
Schedule 
Activity 
Design complete                              Q4 2024 
Construction Notice to Proceed (First PLB)        Q1 2025 
Substantial completion (Final PLB)                Q2 2027 
Cost Breakdown                                     This Request           Total Project 
Design                                                  $4,752,000             $4,902,000 
Construction                                           $12,098,000            $12,098,000 
Total                                                        $16,850,000             $17,000,000 

ALTERNATIVES AND IMPLICATIONS CONSIDERED 
Alternative 1 – Status Quo. Do not proceed with the project. 
Cost Implications: Approximately $150,000 for Notebook Development and preliminary design
investigations would be expensed. 
Pros: 
(1)   Defers capital investment. 
Cons: 
(1)   Passenger Loading Bridges will be operating beyond their service life. 
(2)   Passenger Loading Bridges will be operating with foundations under old seismic code,
posing significant risks in the case of a seismic event. 
(3)   Emergency PLB replacements will cost more and have a greater impact to operations. 
(4)   Increased risk of unplanned gate outages. 
(5)   Smaller separate project will be needed to replace components of PLB to keep it
operational. 
(6)   Outdated technology may not support other bridge improvements (Safedock, Jetdock). 
This is not the recommended alternative. 






Template revised June 27, 2019 (Diversity in Contracting).

             COMMISSION AGENDA – Action Item No. 8g                                   Page 4 of 5 
Meeting Date: October 24, 2023 
Alternative 2 – Proceed with project as scoped. PLB Replacement, 400Hz Gatebox Replacement,
PLB Replacements/Modifications 
Cost Implications: $17,000,000 in capital costs. 
Pros: 
(1)   Replace all six PLBs that area nearing their end of service life. 
(2)   Upgrade PLB foundations to adhere to current code requirements. 
(3)   Replace four aging 400Hz gate boxes. 
(4)   Install new equipment with capacity for future improvements. 
Cons: 
(1)   Capital costs. 
This is the recommended alternative. 
FINANCIAL IMPLICATIONS 
Cost Estimate/Authorization Summary              Capital        Expense           Total 
COST ESTIMATE 
Original estimate                                $24,800,000               $0     $24,800,000 
Current change                               ($7,800,000)              $0    ($7,800,000) 
Revised estimate                               $17,000,000              $0     $17,000,000 
AUTHORIZATION 
Previous authorizations                            $150,000               $0        $150,000 
Current request for authorization               $16,850,000               $0     $16,850,000 
Total authorizations, including this request      $17,000,000               $0     $17,000,000 
Remaining amount to be authorized                    $0             $0             $0 
The change in cost from the original Status 2 estimate is due to (1) a reduction in the number of
PLB replacements for this project; (2) further scope clarification regarding each PLBs foundation
requirements (modification vs. full replacement); and (3) better accuracy of scope and activity
costs, based on lessons learned from previous PLB Renewal and Replacement phases. 
Annual Budget Status and Source of Funds 
The PLB Renewal & Replacement Phase 4 (CIP #C801308) was included in the 2023-2027 capital
budget and plan of finance with a budget of $24,800,000. The capital decrease of $7,800,000 was
transferred to theAeronautical Allowance1 CIP C800753 resulting in no net change to the Airport
capital budget. This project will be submitted for Majority-In-Interest approval from the airlines 

1 The Aeronautical Allowance is included in the Capital Improvement Plan to ensure funding capacity for
unspecified projects, cost increases for existing projects, new initiatives, and unforeseen needs. This ensures funding
capacity for unanticipated spending within the dollar amount of the Allowance CIP. 

Template revised June 27, 2019 (Diversity in Contracting).

             COMMISSION AGENDA – Action Item No. 8g                                   Page 5 of 5 
Meeting Date: October 24, 2023 
in December 2023. The funding sources will be the Airport Development Fund and revenue
bonds. 
Financial Analysis and Summary 
Project cost for analysis              $17,000,000 
Business Unit (BU)                  Passenger Loading Bridges 
Effect on business performance     NOI after depreciation will increase due to inclusion of
(NOI after depreciation)             capital (and operating) costs in airline rate base 
IRR/NPV (if relevant)                N/A 
CPE Impact                       $0.05 in 2028 
Future Revenues and Expenses (Total cost of ownership) 
This project will likely have no impact on Aviation Maintenance operating & maintenance (O&M)
costs. This is a renewal and replacement project that replaces PLBs that are old. Replacement will
require a similar level of maintenance. Therefore, there will not be a material impact on Aviation
O&M costs. 
ATTACHMENTS TO THIS REQUEST 
(1)   Presentation slides. 
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS 
None. 









Template revised June 27, 2019 (Diversity in Contracting).