COMMISSION 
AGENDA MEMORANDUM                        Item No.          10a 
ACTION ITEM                            Date of Meeting      March 14, 2023 

DATE :     March 7, 2023 
TO:        Stephen P. Metruck, Executive Director 
FROM:    Laurel Dunphy, Director Airport Operations 
Eileen Francisco, Director Aviation Project Management Group 
SUBJECT:  Widen Arrivals Roadways (CIP #C800866) 
Amount of this request:              $73,600,000 
Total estimated project cost:         $89,500,000 
ACTION REQUESTED 
Request Commission authorization for the Executive Director to (1) advertise and award up to
three major public works contracts; (2) execute utility agreements for the relocation of utilities;
(3) transfer $527,000 of budget from C800862 Terminal Security Enhancements to support the
installation of security bollards; (4) transfer up to $3,860,000 of budget from C801042 Landside
Pavement Program to support additional pavement rehabilitation, and (5) and authorize an
additional $73,600,000 for a total project authorization of $89,500,000 for the Widen Arrivals
Roadways project at Seattle-Tacoma International Airport. 
EXECUTIVE SUMMARY 
This authorization supports the construction of the Widen Arrivals Roadways project that
provides the necessary roadway capacity for Airport parking and ground transportation
operations.  This project will be delivered through multiple  design-bid-build construction
contracts and supported by the separate procurement of long lead items and multiple utility
relocation agreements. The overall project cost has increased from $79,100,000 to $89,500,000
due to higher than anticipated  escalation, additional costs due to project phasing  and
coordination requirements, enhanced landscaping requirements, and additional scope increases.
Additional airline majority-in-interest approval is not required for this project. 
This project will also install the final security bollards as originally envisioned as part of the
Terminal  Security  Enhancements  project,  and  complete  pavement  rehabilitation  scope
envisioned as part of the Landside Pavement Program project. 
JUSTIFICATION 
This project supports the following Century Agenda strategic goals and objectives: 

Template revised January 10, 2019.

             COMMISSION AGENDA – Action Item No. 10a                                 Page 2 of 7 
Meeting Date: March 14, 2023 
1)  Advance this region as a leading tourism destination and business gateway by meeting the
region’s air transportation needs by delivering vital facilities and infrastructure in a
sustainable and cost-effective manner. 
2)  Be the greenest and most energy efficient Port in North America by meeting or exceeding
agency requirements for storm water leaving Port-owned or operated facilities. 
3)  Be a model for equity, diversity, and inclusion by increasing utilization of Women and
Minority Business Enterprise (WMBE) and Disadvantage Business Enterprise (DBE) DBE firms
and eliminate disparity of access to opportunities. 
The terminal roadway system was originally designed in 1968 to support an overall activity level 
of 25 million annual passengers (MAP). Over the years several efforts have been completed to
extend the life of the terminal roadway system. These include relocating commercial ground
transportation services to the third floor Ground Transportation Center and Northeast Ground
Transportation Lot, extending the Arrivals curbside to the south for public transit and commercial
ground transportation, and relocating rental car customers off-site to the consolidated Rental
Car Facility. 
Approximately 45.9 million passengers used the airport in 2022, and Arrivals experienced
recurring congestion at peak travel times daily. Widening of roadways accessing Arrivals and the
Main Garage will improve access to parking, ground transportation center, and curbsides by
alleviating congestion and reducing queuing on the main roadway entrances for airport visitors
and passengers. The project will enhance roadway safety to accommodate the existing passenger
activity. With no improvements, studies have indicated that the queueing on the Northern
Airport Expressway will reach the I-5/I-405 South Center interchange on a regular basis during
the summer months. 
Diversity in Contracting 
There will be a 9% federally certified Disadvantaged Business Enterprises (DBE) requirement for
the Widen Arrivals Roadway contract. The project team will work with diversity and contacting
on the goal for the separate major works contracts. 
DETAILS 
The Widen Arrivals Roadways project includes the widening of the southbound lanes of the
Northern Airport Expressway to provide an additional two lanes for a total of six lanes from South
170th Street into the Departures and Arrivals curbsides and Main Garage. This requires the
relocation and expansion of the roadways to the west given the location of the columns
supporting the Light Rail Transit guideway. In addition to the improvements described above, the
project will relocate the north rental car transit curb further north to increase utilization of the
Arrivals curbside. The scope of work for this project has increased to include additional utility
relocations and the renewal of utility infrastructure impacted by the project. As an enabling
action the project has already completed the demolition of the fourth-floor bridge from

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

             COMMISSION AGENDA – Action Item No. 10a                                 Page 3 of 7 
Meeting Date: March 14, 2023 
Departures to the Main Garage that was closed with the construction of the light rail transit
walkway. 
On June 14, 2021, the Port of Seattle issued a determination of non-significance for the Widen
Arrivals Roadways project. A State Environmental Policy Act (SEPA) checklist was completed and
was the basis for that determination. 
The budget for Widen Arrivals Roadways has increased from $79.1M to $89.5M predominantly
due to four  factors: 1) $5.0M for additional costs associated with project phasing and
coordination including storm water management; 2) $2.9M for higher than anticipated cost
escalation for electrical equipment, traffic control labor, and fuel; 3) $1.9M increased landscaping
costs to reflect the Landscape Master Plan vision; and 4) $1.1M for additional scope changes
including cameras to support operations, the removal of abandoned industrial wastewater
system infrastructure, and an alignment shift supporting operations during future roadway
construction. 
The project will be delivered through four design-bid-build major works contracts.  The first
contract is complete and included the early demolition of the fourth-floor bridge between
Departures and the Main Garage. The second contract will complete the roadway realignment,
lane additions, and utility system infrastructure improvements and will utilize a project labor
agreement. The second contract will also be supported by multiple utility relocation agreements,
and potentially the procurement of long lead items.  Staff is currently evaluating the risks
associated with owner procurement for these items. The third contract will construct the transit 
canopy for rental car transit operations. The fourth contract would provide  additional
landscaping in areas that would be impacted by the future Sustainable Airport Master Plan 
(SAMP) Near-Term Projects. This fourth contract may or may not be implemented depending
upon the implementation of the SAMP Near-Term Projects. 
Art is planned to be incorporated within this project in two areas. The first is the airfield retaining
wall visible from the Northern Airport Expressway, portions of the Main Garage, and the Light
Rail Transit station. The second is within the north rental car transit stop which will be visible
from the Arrivals curbside, portions of the Main Garage, and by rental car customers. 
Scope of Work 
The Widen Arrivals Roadway project is a roadway improvement project. These types of projects
generally include paving, sidewalks, barriers/curbs, pavement markings, illumination, storm
drainage, retaining walls, signage, sign structures, safety elements (e.g., attenuators), and
Intelligent Transportation Systems (ITS) improvements. 
As part of the improvements to the north rental car transit curb this project will install the
remaining security bollards at the north end of the Arrivals curbside.  These were originally
included with the Terminal Security Enhancements project, but this request will transfer that

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

             COMMISSION AGENDA – Action Item No. 10a                                 Page 4 of 7 
Meeting Date: March 14, 2023 
scope and budget to this project to complete. This reduces the overall costs to the Port since
rework will be avoided.
This project will also complete additional pavement rehabilitation scope on Air Cargo Road and
the southbound lanes of the Northern Airport Expressway. This work was originally envisioned 
as part of the Landside Pavement Program, but this request will transfer that scope and budget
to this project to complete.  The Widen Arrivals Roadways project was completing pavement
rehabilitation scope on those same roadways so combining these efforts reduces the overall
costs to the Port. 
Schedule 
Widen Arrivals Roadway 
Construction start                                2023 Quarter 3 
In-use date                                       2026 Quarter 1 
Widen Arrivals Transit Canopy 
Design Complete                              2023 Quarter 3 
Construction start                                2023 Quarter 4 
In-use date                                       2024 Quarter 1 
Widen Arrivals Landscaping (if contracted) 
Design Start                                      2025 Quarter 1 
Design Complete                              2025 Quarter 2 
Construction start                                2025 Quarter 4 
In-use date                                       2026 Quarter 1 
Cost Breakdown                                     This Request           Total Project 
Design                                                 $18,800,000            $22,800,000 
Construction                                           $54,800,000            $66,700,000 
Total                                                        $73,600,000             $89,500,000 
ALTERNATIVES AND IMPLICATIONS CONSIDERED 
Alternative 1 – The Widen Arrivals Roadways project is not constructed. No improvements are
completed until the SAMP Near-Term Project relocates the southbound lanes to support the
development of the second terminal. 
Cost Implications: $7,590,000 
Pros: 
(1)   No significant capital investment in the short-term. 
Cons: 
(1)   Due to existing capacity constraints significant congestion and queueing occurs each
day on the southbound lanes of the Northern Airport Expressway. Delay times are 
anticipated to exceed 25 minutes. 

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

             COMMISSION AGENDA – Action Item No. 10a                                 Page 5 of 7 
Meeting Date: March 14, 2023 
(2)   The project costs to date would need to be expensed. 
This is not the recommended alternative. 
Alternative 2 – Widening of the southbound lanes of the Northern Airport Expressway to provide
an additional lane. The north rental car transit curb is not relocated. 
Cost Implications: $82,500,000 
Pros: 
(1)   Lower capital investment in the short-term. 
(2)   Provides congestion relief. 
Cons: 
(1)   Additional improvements would be required to support Airport operations. 
(2)   Requires reconstruction of improvements. 
(3)   Does not relocate the rental car transit curb to maximize the passenger load/unload
space in front of the terminal. 
This is not the recommended alternative. 
Alternative 3 – Widening of the southbound lanes of the Northern Airport Expressway to provide
an additional two lanes. The north rental car transit curb is relocated. 
Cost Implications: $89,500,000 
Pros: 
(1)   Provides congestion relief. 
(2)   Minimizes reconstruction; accommodates future projects. 
(3)   Maximizes the passenger load/unload space in front of the terminal 
Cons: 
(1)   Requires significant capital investment in the short-term. 
This is the recommended alternative. 






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

             COMMISSION AGENDA – Action Item No. 10a                                 Page 6 of 7 
Meeting Date: March 14, 2023 
FINANCIAL IMPLICATIONS 
Cost Estimate/Authorization Summary              Capital        Expense           Total 
COST ESTIMATE 
Original estimate                                $15,600,000               $0     $15,600,000 
Previous changes – net                         $78,800,000        $300,000     $79,100,000 
Current change                                $10,451,000       $(51,000)    $10,400,000 
Revised estimate                               $89,251,000        $249,000     $89,500,000 
AUTHORIZATION 
Previous authorizations                         $15,900,000               $0     $15,900,000 
Current request for authorization               $73,351,000        $249,000     $73,600,000 
Total authorizations, including this request      $89,251,000        $249,000     $89,500,000 
Remaining amount to be authorized                    $0             $0             $0 
Annual Budget Status and Source of Funds 
This project (CIP #C800866) was included in the 2023-2027 capital budget and plan of finance
with a budget of $78,800,000. A budget increase of $10,451,000 was transferred from the
Aeronautical Allowance (CIP #C800753) for a total revised capital budget of $89,251,000 resulting
in no net change to the Airport capital budget. The funding sources for this project will be the
Airport Development Fund (ADF), Airport Improvement Program grant, and future revenue
bonds. 
Financial Analysis and Summary 
Project cost for analysis              $89,500,000 
Business Unit (BU)                  Roadways 
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                       $0.16 in 2027 
Future Revenues and Expenses (Total cost of ownership) 
This project will not have a significant impact on Aviation Maintenance annual operating and
maintenance (O&M) costs. Lighting will be a low maintenance LED system; the surface area of
asphalt will increase but otherwise the operating and maintenance costs would not significantly
change. The installation of ITS systems, additional signage, and landscaped areas are anticipated
to increase costs. 
ATTACHMENTS TO THIS REQUEST 
(1)   Presentation slides 

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

             COMMISSION AGENDA – Action Item No. 10a                                 Page 7 of 7 
Meeting Date: March 14, 2023 
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS 
January 22, 2019 – The Commission authorized design for $8,340,000. 
November 11, 2021 – The commission authorized construction demolition of the fourth floor
bridge and contract increase of $6,900,000. 
June 28, 2022 – The Commission authorized the award of an irregular bid for an additional
$600,000. 
















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