COMMISSION 
AGENDA MEMORANDUM                        Item No.          8d 
ACTION ITEM                            Date of Meeting       August 8, 2023 

DATE :     July 31, 2023 
TO:        Stephen P. Metruck, Executive Director 
FROM:    Eileen Francisco, Director Aviation Project management
Laurel Dunphy, Director Airport Operations 
SUBJECT:  N14 Wide-Body and N15 Narrow-Body Common Use Gates (C801333) 
Amount of this request:               $3,875,000 
Total estimated project cost:          $9,380,500 
ACTION REQUESTED 
Request Commission authorization for the Executive Director to authorize $3,875,000 for final
design, preparation of construction bid documents, and the procurement of long-lead material
items for the N14 Wide Body and N15 Narrow Body Common-Use Gates at Seattle-Tacoma
International  Airport  (SEA).  This  request  is  for  $3,875,000  for  a  total  authorization  of
$4,170,000. 
EXECUTIVE SUMMARY
Planned upcoming construction projects will place a premium on the need for Wide-Body (WB)
aircraft gates at SEA as several WB gates will be taken out of service. The N14 WB and N15
Narrow-Body (NB) Common Use Gates Project converts Gate N14 to be used for WB aircraft
operations including international departures, while allowing Gate N15 to operate as a
common-use NB aircraft gate, although not simultaneously. The project will also improve WB
aircraft flexibility for Gate N16 through the addition of a starboard fuel hydrant pit (FHP) and
associated  infrastructure  improvements.  The long-lead  material purchase  maintains the
construction schedule for Summer/Fall 2024. 
JUSTIFICATION
There are limited number of WB aircraft gates at SEA, and several WB gates will be taken out of
service because of upcoming planned construction projects, including reconstruction of the S
Concourse, which will severely limit flight scheduling flexibility.


Template revised January 10, 2019.

             COMMISSION AGENDA – Action Item No. 8d                                  Page 2 of 7 
Meeting Date: August 8, 2023 
This project will help mitigate the impacts of WB aircraft gate outages during planned
construction, as it is necessary to meet current airport demand. Gate N14 improvements
include apron Portland cement concrete pavement (PCCP) panels, lighting, pre-conditioned air
(PCAir),  400  Hz  power,  Safedock,  striping  and  two  fuel  hydrant  pits  and  associated
infrastructure. Additionally, this project includes adding a starboard fuel hydrant pit (FHP) and
associated infrastructure improvements at Gate N16. 
The project will improve safety, reduce emissions, and improve operational efficiencies at Gates
N14 and N16. 
•   Safety  improvements  include  the  reduction  of  fuel  trucks  operating  within  the
congested apron environment. 
•   Emissions reductions will be realized through upgrading ground power (400 Hz) and
PCAir units servicing WB aircraft at Gate N14 allowing airlines to shut down on-board
aircraft power units when parked at Gate N14. 
•   Operational efficiencies will be gained as Gates N14 and N16 will provide all airlines with
the ability to fuel either (or both) wing(s) of their WB aircraft, providing necessary gate
scheduling flexibility during planned construction projects. 
Diversity in Contracting 
The project team has been working with the Diversity in Contracting Department and will be
returning to the Commission for construction authorization along with an aspirational goal for
women and minority business enterprises (WMBE) participation in the construction contract.
The design services contract (P-00320884) includes a 15% WMBE participation requirement and
is currently trending below the requirement. However, Service Directive (SD) and associated 
Modification for this project are estimated to provide 30% utilization, which will help the
overall Service Agreement utilization. The project management services contract (P-00320718)
includes  a  16%  WMBE  participation  requirement  and  is  currently  trending  above  the
requirement. The SD and associated Modifications for this project are estimated to continue
the positive trend with an estimated 23% utilization. 
Long-lead Material Procurement 
Certain construction materials and necessary project equipment may have lead times exceeding
standard contractor mobilization time frames. The project team has been analyzing the
construction bidding market to identify these critical material items including, but not limited to 
utility covers, high mast light poles/luminaires, hydrant fuel pits, PCAir units, and Safedock
units. Early procurement of these items as owner furnished/contractor installed (OFCI) items 
will help maintain the construction schedule and planned gate closures for Summer/Fall 2024.
As final design progresses the project team will confirm critical OFCI items and work with the
Central Procurement Office (CPO) to develop the most effective path forward. 


(Diversity in Contracting).

             COMMISSION AGENDA – Action Item No. 8d                                  Page 3 of 7
Meeting Date: August 8, 2023 
DETAILS 
Final design for the project will investigate “islands” of old pavement surrounded by recently
constructed PCCP panels and evaluate the cost-benefits of replacing the pavement now versus
deferral. The design team will review pavement markings for standards compliance. Passenger
loading bridge (PLB) configurations will be reviewed for WB aircraft at gates N14 and N16. The
project will include improved apron lighting along with new high mast light foundation(s). The
design  team  will  also  provide  specifications  for  temporary  lighting,  and  associated
maintenance, during construction. 
The project team will design three new FHP locations and associated infrastructure, including
emergency shutoff valves. Channel drain locations and alignment within the project limits
adjacent to the new FHP locations will be evaluated for efficacy to contain fuel spills. 
The following ground support infrastructure will be reviewed and confirmed or designated for
improvement through the project: 
(1) Potable water connections.
(2) Electric  ground  support  equipment  (eGSE)  charging  stations,  including  access  and
staging.
(3) Aircraft fueling systems.
(4) PCAir to accommodate WB aircraft.
(5) 400 Hz power to accommodate WB aircraft.
(6) SafeDock locations and settings to accommodate WB aircraft.
The project will be combined with other airfield projects as a single construction contract for
economies of scale, lower administrative costs, and lower impacts to airfield operations than
from multiple construction contracts. The project team will be working with the Labor Relations 
Department and will be returning to the Commission for construction authorization along with
a determination of applicability for a Project Labor Agreement (PLA) as part of the construction
contract.
Scope of Work
Scope of work for this project is anticipated to include the following improvements:
(1)   Apron pavement replacement at Gates N14, N15, and N16.
(2)   Supplemental lighting installations at Gate N14.
(3)   PCAir unit for WB aircraft at Gate N14.
(4)   400 Hz power unit for WB aircraft at Gate N14.
(5)   SafeDock aircraft guidance system unit for WB aircraft at Gate N14.
(6)   Airfield markings (striping) at Gates N14, N15, and N16.
(7)   Fuel hydrant pits and associated infrastructure.
a.  Two at Gate N14.
b.  One at Gate N16.

(Diversity in Contracting).

             COMMISSION AGENDA – Action Item No. 8d                                  Page 4 of 7
Meeting Date: August 8, 2023 
Schedule
Activity 
Commission construction authorization          2024 Quarter 1 
Construction contract execution                 2024 Quarter 2 
Construction start                                2024 Quarter 3 
In-use date                                       2024 Quarter 4 
Cost Breakdown                                    This Request            Total Project 
Design                                                $1,375,000               $1,670,000 
Construction                                           $2,500,000               $7,710,500 
Total                                                       $3,875,000                $9,380,500 
ALTERNATIVES AND IMPLICATIONS CONSIDERED 
Three alternatives were considered ranging from a no project alternative through the
requested authorization for the recommended alternative. Narrative, cost implications, pros,
and cons for each alternative are provided below. 
Alternative 1 – Status quo (no project alternative). This alternative considers the pros and cons
of not moving forward with the project scope described above.
Cost Implications: No capital or expense costs.
Pros:
(1)   Gate N14 operations continue without interruption. 
(2)   Gate N16 operations continue without interruption.
Cons:
(1)   Gate N14 not fully capable to accommodate WB aircraft.
(2)   No hydrant fueling capability for the current interim WB aircraft parking position at
Gate N14.
(3)   Gate N16 not fully capable to accommodate WB aircraft.
(4)   Slower WB aircraft turns due to slower fueling operations at Gate N16.
(5)   Loss of fuel system redundancy in the event the existing FHP at Gate N16 requires
maintenance or in the event of aircraft maintenance on the port side of the WB
aircraft at Gate N16. 
This is not the recommended alternative. 




(Diversity in Contracting).

             COMMISSION AGENDA – Action Item No. 8d                                  Page 5 of 7
Meeting Date: August 8, 2023 
Alternative 2 – N14/N15 Only. (No additional FHP at Gate N16). This alternative considered the
full project scope described above, limited to just the work areas for Gate N14 and Gate N15.
Cost Implications: 7,152,300.
Pros:
(1)   Gate N14 fully capable of accommodating WB aircraft.
(2)   Gate N16 operations continue without interruption.
(3)   Potential capital cost savings.
Cons:
(1)   Gate N16 not fully capable to accommodate WB aircraft.
(2)   Slower WB aircraft turns due to slower fueling operations at Gate N16.
(3)   Loss of fuel system redundancy in the event the existing FHP at Gate N16 requires
maintenance or in the event of aircraft maintenance on the port side of the WB
aircraft at Gate N16.
This is not the recommended alternative. 
Alternative 3 – Proposed project. This alternative considered the full project scope described
above. 
Cost Implications: 9,380,500 
Pros:
(1)   Gate N14 fully capable of accommodating WB aircraft.
(2)   Gate N16 fully capable of accommodating WB aircraft.
(3)    Meet current airport operational demand.
(4)   Help mitigate the impacts of WB aircraft gate outages during planned construction. 
Cons:
(1)   Temporary  interruption  to  Gate  N14  and  Gate  N15  operations  during  phase  1
construction.
(2)   Temporary interruption to Gate N16 operations during phase 2 construction.
This is the recommended alternative. 






(Diversity in Contracting).

             COMMISSION AGENDA – Action Item No. 8d                                  Page 6 of 7
Meeting Date: August 8, 2023 
FINANCIAL IMPLICATIONS 
Cost Estimate/Authorization Summary              Capital        Expense           Total 
COST ESTIMATE 
Original estimate                                 $7,390,000               $0      $7,390,000 
Current change                                $1,990,500               0      $1,990,500 
Revised estimate                                $9,380,500              $0      $9,380,500 
AUTHORIZATION 
Previous authorizations                            $295,000                0        $295,000 
Current request for authorization                $3,875,000                0       3,875,000 
Total authorizations, including this request       $4,170,000                0      $4,170,000 
Remaining amount to be authorized            $5,210,500             $0     $5,210,500 
Annual Budget Status and Source of Funds 
The N14 Wide-Body and N15 Narrow-Body Common Use Gates (CIP #C801333) is included in
the 2023-2027 capital budget and plan of finance with a budget of $7,390,000. The capital
increase of $1,990,500 was transferred from the Aeronautical Allowance1 CIP C800753 resulting
in no net change to the Airport capital budget. The funding sources will be the Airport
Development Fund and existing revenue bonds. 
Financial Analysis and Summary 
Project cost for analysis              $9,380,500 
Business Unit (BU)                  Gates 
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                       $0.03 in 2025 
Future Revenues and Expenses (Total cost of ownership) 
An increase in annual operating & maintenance (O&M) costs is anticipated as a result of this
project providing additional infrastructure to support larger aircraft activity. This will primarily
affect the Electronic Technicians, with having an additional SafeDock unit, boarding gate
readers, cameras, access controls and common use equipment to maintain in support of
widebody operations. This will result in an annual increase of approximately 240 labor hours for
Electronic Technicians.

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. 

(Diversity in Contracting).

             COMMISSION AGENDA – Action Item No. 8d                                  Page 7 of 7
Meeting Date: August 8, 2023 
ADDITIONAL BACKGROUND 
The Project was originally studied as part of North Satellite Modernization. Due to reduced
aviation demand driven by the pandemic, Alaska Airlines previously notified the Port of Seattle
(Port) that they did not require all 20 gates at NSAT for their operations when the facility
opened.  In response, Port  staff identified an opportunity to convert four NSAT gates to
common-use (CUSE) operations. Gates N1 and N2 would serve CUSE narrow-body (NB)
domestic aircraft, and gates N15 and N16 were provisionally selected to accommodate widebody
aircraft for international departures. 
Subsequently, Evaluation of Potential WB & NB CUSE Gates at NSAT, published by AECOM on
September 20, 2021, looked at the potential conversion of N14, N15, or N16 to accommodate
WB aircraft. Ultimately the evaluation determined N14 and N16 to be viable candidates for
conversion. 
ATTACHMENTS TO THIS REQUEST 
(1)   Presentation slides.
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS 
None.










(Diversity in Contracting).