COMMISSION 
AGENDA MEMORANDUM                        Item No.          8b 
ACTION ITEM                            Date of Meeting    September 10, 2019 
DATE:     September 3, 2019 
TO:        Stephen P. Metruck, Executive Director 
FROM:    Jeffrey Brown, Director Aviation Facilities and Capital Programs 
Wayne Grotheer, Director, Aviation Project Management Group 
SUBJECT:  Passenger Loading Bridge Renewal  & Replacement  Phase 2  -  Budget Increase
Request (CIP #C800793) 
Amount of this request:               $3,000,000 
Total estimated project cost:         $13,000,000 
ACTION REQUESTED 
Request Commission authorization for the Executive Director to (1) increase the project budget
for the Passenger Loading Bridge (PLB) renewal & replacement project in the amount of
$3,000,000; (2) use Port of Seattle crews, and small and major works on-call contracts to
perform the construction work; and (3) advertise, bid, and execute a major works construction
project. This request is $3,000,000 for a revised total estimated project cost of $13,000,000. 
EXECUTIVE SUMMARY 
Critical structural failures, unforeseen site conditions, and addition of new systems since the
project was scoped have increased the cost to replace the PLBs. This request will provide the
necessary funding to complete the replacement of the nine PLBs and fixed walkways. Reliable,
well-operating PLBs are critical to airline and airport operations. Port staff has created a
prioritized list of PLBs, whose age and condition indicate a need for replacement. Three of the
nine PLBs and associated fixed walkways (S6, S11, and C15) have already been replaced and the
others (B10, C9, C11, C18, D4, and D11) are at the highest risk for failure. 
JUSTIFICATION 
The PLBs at Sea-Tac have high utilization compared to airports with comparable annual
enplanements. In 2018, Sea-Tac processed approximately 312,000 passengers per bridge, well
above the average of the top 20 airports of approximately 209,000 passengers. 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 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

Template revised January 10, 2019.

COMMISSION AGENDA  Action Item No. _8b_                                Page 2 of 7 
Meeting Date: September 10, 2019 
airline operations. This has occurred with Gate C15, December 2017, being inoperable for
almost a month because of a failed, obsolete motor generator set. Another failure occurred at
Gate S12, May 2019, after a quarterly inspection found the structure to be critical; which
required the PLB shut down for a significant amount of time to make temporary repairs until
the PLB can be replaced. 
Diversity in Contracting 
The major works contract has a five percent aspirational goal for women- and minority-owned
business enterprise (WMBE). No specific diversity in contracting goals were originally set for
this project, however, the SWMBE achievements to date are 23.8 percent. 
DETAILS 
Aviation Project Management has worked in conjunction with AV Operations, AV Planning, AV
Facilities and Infrastructure, and AV Maintenance to create a prioritized list of PLBs whose age
and condition are cause for replacement or refurbishment. The additional funds will be used to
complete the replacement of nine bridges covered under CIP# C800793. 
Several factors, as detailed below, have driven the increased cost to replace the PLBs and fixed
walkways: 
Gate S6 failed before it was scheduled to be replaced. The expedited replacement
incurred additional costs and impacted the other PLB schedules. Other structural
modifications, seismic upgrade requirements, telecommunications upgrades, and 400
Hz aircraft power modifications resulted in design and construction changes. This PLB is
complete. 
Gate S11 had a severely damaged anchor bolt for one of the foundations requiring a
new foundation. Other structural modifications, differing site conditions, utility conflicts, 
and seismic upgrade requirements resulted in design and construction changes. This PLB
and fixed walkway are complete. 
The foundation for Gate C15 needed to be redesigned and constructed differently with
a deeper foundation. This resulted from unknown utilities and differing site conditions. 
This PLB is installed and in close-out. 
The foundation for Gate C11 needs to be redesigned and constructed differently with a
deeper foundation. This resulted from unknown utilities and differing site conditions. 
Gate D4 has an issue with the Pre-Conditioned Air hydronic piping not having isolation
valves that allow for the replacement of the PLB. The lack of isolation valves requires the
system to be drained and valves installed prior to bridge replacement. 

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

COMMISSION AGENDA  Action Item No. _8b_                                Page 3 of 7 
Meeting Date: September 10, 2019 
Gate D11 has two fixed walkway foundations, and one rotunda foundation that will
need to be upgraded  to meet seismic code. There is limited area to expand the
foundations due to interference from other buildings and utilities resulting in changes to
design and construction. 
Gate B10 foundation is surrounded by industrial wastewater system lines that will need
to be relocated prior to adding a new foundation that meets current seismic code. Three
manholes (two 48  inch  and one 60  inch) will be installed to  meet drainage
requirements. These modifications to design and construction were a result of differing
site conditions. Additionally, an abandoned fuel line will need to be remediated and
removed prior to any foundation work.
Gate C9 currently has all the 400Hz aircraft power system routed along the fixed walk -
way which will have to be re-routed prior to replacing the PLB. This bridge has three
foundations that will need to be upgraded to meet the seismic requirements. 
Gate C18 has two fixed walkway sections with three individual foundations that will
need to be modified to meet current seismic code. Differing site conditions, utility
conflicts,  and  seismic  upgrade  requirements  resulted  in  design  and  construction
changes. 
Scope of Work 
(1)   Design services for this scope of work will be provided under existing indefinite
delivery, indefinite quantity (IDIQ) design services contract. 
(2)   Purchase  and  installation  of  new  PLBs,  associated  fixed  walkway,  and  related
components at Gates B10,  C9, C11, C18, D4, and D11 along with necessary
architectural, electrical, data, and mechanical infrastructure upgrades to meet new
PLB standards and current code requirements. Three of the nine PLB's have already
been replaced  S6, S11, and C15. 
(3)   Port  Construction  Services  will  perform  work  associated  with  preparing  the
foundations upgrade or replacement and provide construction management services
for PLB installations at all gates. 
(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 Maintenance for
faster response. 
Schedule 
Replacement Schedule: 
1.  4Q 2019: D4 & B10 
2.  1Q 2020: D11 
3.  4Q 2020: C11 & C18 
4.  1Q 2021: C9 

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

COMMISSION AGENDA  Action Item No. _8b_                                Page 4 of 7 
Meeting Date: September 10, 2019 
*This schedule is tentative and can change due to changing conditions and priorities. 
Activity 
Commission design authorization               2018 Quarter 1 
Design start                                       2018 Quarter 2 
Commission construction authorization          2018 Quarter 1 
Construction start                                2018 Quarter 4 
In-use date                                       2021 Quarter 1 
Cost Breakdown                                      This Request          Total Project 
Design                                                     $500,000            $2,100,000 
Construction                                              $2,500,000           $10,900,000 
Total                                                           $3,000,000            $13,000,000 
ALTERNATIVES AND IMPLICATIONS CONSIDERED 
Alternative 1  Complete only the bridges that the current funding allows (7 bridges of 9
planned) 
Cost Implications: $0, No additional funds would be required. 
Pros: 
(1)   This alternative minimizes the capital input by only replacing 7 of the 9 planned
bridges. 
Cons: 
(1)   This alternative would significantly degrade the quality of passenger experience at
Sea-Tac. 
(2)   This alternative would potentially lead to airlines insisting on processing departing
passengers in severely congested hold rooms on other concourses already being used
for other flights. 
(3)   This alternative does not provide reliable gate capacity for the increasing number of
flights. 
(4)   This alternative does not give airlines, tenants, and passengers a reliable gate system
to provide customer service and process guest for arrivals and departures. 
(5)   This alternative does not address the need to replace the aging bridges that could lead
to a significant failure causing increased cost and downtime to replace. 
(6)   This alternative does not address the need to update the bridge foundations to meet
the current seismic regulations. 
This is not the recommended alternative. 


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

COMMISSION AGENDA  Action Item No. _8b_                                Page 5 of 7 
Meeting Date: September 10, 2019 
Alternative 2  Delay replacement of the two (2) planned bridges to a later project. 
Cost Implications: $3,000,000 plus escalation costs added to a future project to re-start the
replacement effort. Replacement timeline would be pushed out approximately 1.5 years for a
new project to be created and approved. 
Pros: 
(1)   This alternative delays the capital requirement. 
Cons: 
(1)   This alternative will delay the replacement of the walk ways and bridges that have
been identified as critical. 
(2)   This alternative does allow for efficient use of PCS construction crews during the dry
season for foundation work. 
(3)   This alternative carries a risk of a premature failure of a bridge leading to extended
closure time and increased cost for expedited replacement. 
(4)   This alternative does not provide reliable gate capacity for the increasing number of
flights. 
(5)   This alternative does not give airlines, tenants, and passengers a reliable gate system
to provide customer service and process guest for arrivals and departures. 
(6)   This alternative does not address the need to replace the aging bridges that could lead
to a significant failure causing increased cost and downtime to replace. 
(7)   This alternative will increase the cost of future replacement projects. 
This is not the recommended alternative. 
Alternative 3  Increase the funding to complete the scope of work for all nine bridges. 
Cost Implications: $3,000,000 
Pros: 
(1)   Complete the planned bridge replacements and upgrade the foundations to meet the
seismic code. 
(2)   Relocate added equipment from the bridge to a permanent location and off the bridge
structure. 
(3)   The replaced bridge will have a new service life. 
(4)   This alternative will give the airlines, tenants, and passengers a reliable gate system to
provide customer service and process guest for arrival and departures. 
(5)   This alternative will keep the bridge replacement on the existing timeline. 
(6)   This alternative allows for construction flexibility with the PCS crews to complete the
more complicated foundation work. 
Cons: 
(1)   None 
This is the recommended alternative. 

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

COMMISSION AGENDA  Action Item No. _8b_                                Page 6 of 7 
Meeting Date: September 10, 2019 
FINANCIAL IMPLICATIONS 
The Passenger Loading Bridges Project CIP #C800793 is included in the 2019-2023 capital
budget and plan of finance with a budget of $10,000,000. A budget increase of $3,000,000 was
transferred from the Aeronautical Reserve CIP C800753 resulting in zero net change to the
Aviation capital budget. The funding sources would be the Airport Development Fund and
revenue bonds. This project was approved by the airlines through a Majority-in-Interest (MII) 
vote in 2017. Due to the cost increase, the project will require additional MII approval. 
Cost Estimate/Authorization Summary               Capital        Expense           Total 
COST ESTIMATE 
Original estimate                                $10,000,000               $0     $10,000,000 
Current change                                 $3,000,000              $0      $3,000,000 
Revised estimate                              $13,000,000              $0    $13,000,000 
AUTHORIZATION 
Previous authorizations                         $10,000,000               $0     $10,000,000 
Current request for authorization                $3,000,000               $0      $3,000,000 
Total authorizations, including this request      $13,000,000               $0     $13,000,000 
Remaining amount to be authorized                    $0             $0             $0 
Annual Budget Status and Source of Funds 
Financial Analysis and Summary 
Project cost for analysis                         $13,000,000 
Business Unit (BU)                            Passenger Loading Bridges 
Effect on business performance (NOI after    NOI after depreciation will increase 
depreciation) 
IRR/NPV (if relevant)                           N/A 
CPE Impact                                 $0.04 in 2022 
Future Revenues and Expenses (Total cost of ownership) 
This is a renewal and replacement program that replaces existing equipment that is old and
dated. Replacement of the equipment will require a similar level of maintenance and an
anticipated reduced level of repairs and does not have a material impact on current Aviation
Maintenance O&M costs. 
ADDITIONAL BACKGROUND 
PLBs were historically predominantly owned by airlines. Over the past fifteen years or so, the
Port has increasingly taken over ownership of PLBs when they needed to be replaced to provide
a consistent level of maintenance and level of service for all PLBs. Currently, Alaska is the only

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

COMMISSION AGENDA  Action Item No. _8b_                                Page 7 of 7 
Meeting Date: September 10, 2019 
airline owning PLBs at Sea-Tac. Upon the completion of this project and the North Satellite
Expansion project, the Port will own and maintain all the PLBs at Sea-Tac. 
ATTACHMENTS TO THIS REQUEST 
(1)   Presentation slides 
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS 
February 27, 2018  The Commission approved $7,700,000 for the design, construction, and
purchase of PLBS at gates C15, C9, D11, C11, C18, S6, D4, and the fixed walkways at C9,
D11, C18, and D4. 
February 28, 2017  The Commission approved $2,300,000 for the design, construction, and
purchase of PLBs at gates S11 and B10 and the fixed walkway at S11. 













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