COMMISSION 
AGENDA MEMORANDUM                        Item No.          8e 
ACTION ITEM                            Date of Meeting      January 12, 2021 
DATE:     December 18, 2020 
TO:        Stephen P. Metruck, Executive Director 
FROM:    Eileen Francisco, Acting Director, Aviation Facilities and Capital Programs 
Wayne Grotheer, Director, Aviation Project Management 
SUBJECT:  Passenger Loading Bridge Renewal and Replacement Phase 3 (CIP#C801180) 
Amount of this request:              $13,850,000 
Total estimated project cost:         $14,000,000 
ACTION REQUESTED 
Request Commission authorization for the Executive Director  to:  (1) Prepare design and
construction bid documents for the replacement of the Passenger Loading Bridges (PLBs) at
Seattle-Tacoma International Airport and ; (2) Purchase seven PLBs, six fixed walkways and seven 
400 Hz gate boxes for specified Gates; (3) Use Port of Seattle crews, as well as small and major
works on-call contracts to perform the construction work. This request is in the amount of 
$13,850,000, for a total estimated project cost of $14,000,000. 
EXECUTIVE SUMMARY 
This project will replace the next set of seven PLBs that are at the end of their service life and/or
have significant maintenance issues, which require a full replacement. Gates C18, C20, D3, D5,
D8, D9, and D10 have been identified to be included in the next phase of this project. The project
will remove the existing equipment, including the columns, install newly constructed equipment
that meets current design standards, and upgrade the foundations for each column, if necessary. 
JUSTIFICATION 
The PLBs at Seattle-Tacoma International Airport (Airport) have high utilization compared to
airports with similar annual enplanements. In 2019, the Airport processed approximately 336,000
passengers per bridge, well above the average of the top 20 airports at approximately 220,000
passengers per bridge. Any unplanned downtime, due to PLB or fixed walkway failure, impacts
airlines and customer service. PLBs have a service life of approximately 25 years before
replacement is required. Many of the replacement parts for 25+ year old PLBs are no longer
available. As a result, repair time is extended, while parts are fabricated or re-manufactured, or
used parts are located from other PLB owners. Unplanned downtime caused by failure of
obsolete parts can extend for several weeks, seriously disrupting airline operations. This occurred
at Gate S12, in May 2019, after a quarterly inspection found the structure to be critically failing. 

Template revised January 10, 2019.

COMMISSION AGENDA  Action Item No. __8e__                              Page 2 of 5 
Meeting Date: January 12, 2021 
This required the PLB to be shut down for a significant amount of time to make temporary repairs
until the PLB could be replaced. 
The work will renew and replace existing assets that are highly utilized by customers and
employees as they travel through the airport. Disruption to the bridge operations have a direct
impact to operations. 
Diversity in Contracting 
The project team intends to increase investment in Women/Minority Business Enterprise 
(WMBE) to ensure their increased access to opportunities by using an existing IDIQ design
contract which has a 24% WMBE aspirational goal. Small works contracts will be administered in
support of this project, and the Diversity in Contracting Department along with the project team
will be conducting outreach to WMBE businesses of the construction opportunities. 
DETAILS 
The Port Construction Services  crew is  knowledgeable and capable of completing the
modifications and replacements. The crew also provides the ability to quickly re-prioritize which
gates are being replaced and the timing. Given the dynamic environment of the Airport and
operations, the project team can respond to challenges and take advantage of opportunities to
complete the replacements. 
Scope of Work 
(1)   Design services for this scope of work will be provided under an existing IDIQ design
service contract. 
(2)   Purchase and installation for PLBs, associated fixed walkway, and related components
at Gates C18, C20, D3, D5, D8, D9, and D10. This includes the necessary architectural,
electrical, data, and mechanical infrastructure upgrades to meet new PLB standards and
current code requirements. 
(3)   PCS  will  perform  work  associated  with  preparing  the  foundations  upgrade  or
replacement and provide construction management services for all PLB installations at
all gates. The foundation for each column will be evaluated to determine if an upgrade
is required for compliance with the 2018 seismic code revision. 
(4)   The new bridges will be connected to the Port's facility monitoring system so any
malfunction that shuts the bridge down will be promptly reported to Airport
Maintenance for faster response. 




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

COMMISSION AGENDA  Action Item No. __8e__                              Page 3 of 5 
Meeting Date: January 12, 2021 
Schedule 
Replacement Schedule: 
2021: Gates C18 & C20 
2022: D3 & D5 
2023: D10 & D9 
2024: D8 
This schedule is tentative and can change due to varying conditions and priorities for gate
outages. The order can change as well, if there are opportunities to overlap outages with other
project closures. 
Activity 
Design start                                       2021 Quarter 1 
Commission construction authorization          2021 Quarter 1 
Construction start                                2021 Quarter 3 
First In-use date                                    2021 Quarter 4 
Last In-use date                                   2024 Quarter 4 
Cost Breakdown                                     This Request           Total Project 
Design                                                  $3,581,000             $3,581,000 
Construction                                           $10,419,000            $10,419,000 
Total                                                        $14,000,000             $14,000,000 
ALTERNATIVES AND IMPLICATIONS CONSIDERED 
Alternative 1  Delay the project 
Cost Implications: Approximately $20,000 would need to be expensed; potential for additional
costs if PLB fails during delay and is rushed to be replaced. 
Pros: 
(1)   Delayed capital investment. 
Cons: 
(1)   Bridges will be operating beyond their service life. 
(2)   Emergency bridge replacements cost more and have a greater impact to operations. 
(3)   Future replacement projects may cost more. 
(4)   Increased risk of gate outages. 
(5)   Separate projects will need to replace smaller components of the bridge to keep it
functional. 
(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. __8e__                              Page 4 of 5 
Meeting Date: January 12, 2021 
Alternative 2  PLB Bridge Replacement Only 
Cost Implications: $13,500,000 
Pros: 
(1) Replace all seven PLBs that are at the end of their service life. 
(2) Upgrade bridge foundation to meet current code requirements. 
(3) Install new equipment with capacity for future improvements. 
Cons: 
(1)   Higher capital investment. 
(2)   Will not replace all 400 Hz gate boxes that are near or beyond end of life. 
(3)   A separate project is required to replace the gate boxes. 
This is not the recommended alternative. 
Alternative 3  PLB Bridge Replacement and New 400 hz Gate Boxes 
Cost Implications: $14,000,000 
Pros: 
(1)   Replace all seven PLBs that are at their service life. 
(2)   Upgrade bridge foundation to meet current code requirements. 
(3)   Install new equipment with capacity for future improvements. 
(4)   Replace seven aging 400 Hz gate boxes. 
Cons: 
(1)   Highest capital investment. 
This is the recommended alternative. 
FINANCIAL IMPLICATIONS 
Cost Estimate/Authorization Summary              Capital        Expense           Total 
COST ESTIMATE 
Original estimate                                $12,165,000               $0     $12,165,000 
Current change                                 $1,835,000               0      $1,835,000 
Revised estimate                               $14,000,000                0     $14,000,000 
AUTHORIZATION 
Previous authorizations                            $150,000                0        $150,000 
Current request for authorization               $13,850,000                0     $13,850,000 
Total authorizations, including this request      $14,000,000                0     $14,000,000 
Remaining amount to be authorized                    $0             $0             $0 


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

COMMISSION AGENDA  Action Item No. __8e__                              Page 5 of 5 
Meeting Date: January 12, 2021 
Annual Budget Status and Source of Funds 
This project (CIP C801180), was included in the 2021-2025 Capital Budget and Plan of Finance
with a budget amount of $12,165,000. A budget increase in the amount of $1,835,000 was
transferred from the Aeronautical Reserve (CIP C800753) resulting in zero net change to the
Aviation capital budget. The funding source will be the Airport Development fund and revenue
bonds. This project was submitted on December 4, 2020, to the airlines for the Majority-in- 
Interest approval. 
Financial Analysis and Summary 
Project cost for analysis              $14,000,000 
Business Unit (BU)                  Passenger Loading Bridge 
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                       $.03 in 2022; $.05 by 2024 

ATTACHMENTS TO THIS REQUEST 
(1)   Presentation slides 
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS 
July 9, 2019 (6F)  Authorization to advertise and award a PLB specific IDIQ contract. 









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