COMMISSION 
AGENDA MEMORANDUM                        Item No.          8f 
ACTION ITEM                            Date of Meeting       April 16, 2024 

DATE:     April 9, 2024 
TO:        Stephen P. Metruck, Executive Director 
FROM:    Eileen Francisco, Director, Aviation Project Management 
Keri Stephens, Director, Aviation Facilities and Capital Programs 
SUBJECT:  Water Reservoir Rehabilitation (C801172) 
Amount of this request:               $2,019,000 
Total estimated project cost:          $3,169,000 

ACTION REQUESTED 
Request Commission authorization for the Executive Director to 1) advertise, award, and execute
a major works construction contract to rehabilitate and provide improvements to the 2-milliongallon
water reservoir at the Port of Seattle, and 2) execute related project change orders,
amendments, work authorizations, purchases, contracts, and take other actions necessary to
support and deliver the Water Reservoir Rehabilitation project within the approved budget, (3)
authorize use of Port of Seattle crews to support the design and construction activities. The
amount of this request is $2,019,000 for a total estimated project cost of $3,169,000. 
EXECUTIVE SUMMARY 
The 2-million-gallon water reservoir at Seattle-Tacoma International Airport is an above ground
steel tank that provides water storage for domestic use and fire suppression to the entire airport.
The September 2021 inspection indicated that severe corrosion has appeared in many areas on
the reservoir and, if not addressed, could result in deformation of the structure. Additionally, the
presence of rust also puts the water quality into jeopardy. This project will rehabilitate the
structure to extend its useful life. 
JUSTIFICATION 
The Department of Health requires that water reservoirs be kept in good operating condition.
The reservoir was built in the year 2000 as a requirement under the National Fire Protection
Association 24 code, ensuring the airport has reliable water on hand (in a tank) to fight any fire
on the airport. Without the rehabilitation efforts the reservoir is at risk of potential structural
failure and water quality degradation. 
Diversity in Contracting 

Template revised January 10, 2019.

             COMMISSION AGENDA – Action Item No. 8f                                   Page 2 of 4 
Meeting Date: April 16, 2024 
This project has established a WMBE aspirational goal of 7%. 
DETAILS 
The water reservoir is located north of the airport off Host Road. The reservoir has a 2 million 
gallon capacity for fire suppression and domestic water. It is generally recommended that water
reservoirs of this type be inspected and cleaned every 3 to 5 years. Previous inspections include
a 2013 dive inspection, 2017 cathodic protection survey, and 2018 dive inspection. The most
recent inspections include a 2021 dive inspection, cathodic protection inspection, and 2022
exterior coating test.
The Department of Health requires that water reservoirs be kept in good, operating condition. 
During construction, the airport’s water source will be switched over from the reservoir to Seattle
Public Utilities. Coordination and planning efforts with Aviation Maintenance, Boiler, and the Fire
Department are underway for this event, as well as giving contractors access to the tank during
construction. 
The project scope requires that the water reservoir be drained completely. Due to environmental
restrictions, the water cannot be drained directly into the sewer. Therefore, storage tanks will be
brought onto the site to hold the water during construction. 
Scope of Work 
The project scope seeks to rehabilitate the structure and extend the asset’s useful life by 20 years
by implementing the following improvements: 
(1) Complete replacement of interior coatings 
(2) Partial replacement of exterior coatings 
(3) Column base plate modifications 
(4) Cathodic protection system improvements 
(5) Rebuild interior and exterior access ladders to meet safety codes 
(6) Installation of davit post sleeve on tank roof 
(7) Replace weathered tank hardware including nuts, bolts, cables, and pulleys 
(8) Install tank sampling ports 
(9) Valve vault improvements and repairs 
(10) Installation of sump pump in valve vault 




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

             COMMISSION AGENDA – Action Item No. 8f                                   Page 3 of 4 
Meeting Date: April 16, 2024 

Schedule 
Activity 
Construction start                                2024 Quarter 3 
In-use date                                       2025 Quarter 2 
Cost Breakdown                                     This Request           Total Project 
Design                                                           $0             $1,150,000 
Construction                                             $2,019,000             $2,019,000 
Total                                                         $2,019,000              $3,169,000 
ALTERNATIVES AND IMPLICATIONS CONSIDERED 
Alternative 1 – Do not proceed with construction. 
Cost Implications: Project team would need to expense $531,472 cost to date. 
Pros: 
(1)   Don’t need to switch water sources 
(2)   No further cost incurred. 
Cons: 
(1)   Will not be in compliance with Washington State Department of Health 
(2)   Reduced usable life of the structure 
(3)   Presents health and safety hazard to the public 
This is not the recommended alternative. 
Alternative 2 – Proceed with the full scope of the Water Reservoir Rehabilitation project. 
Cost Implications: $3,169,000 
Pros: 
(1) Eliminates risk of the tank’s structural integrity becoming compromised. 
(2) Eliminates risk of jeopardizing water quality. 
(3) Some of the additional scope items require the tank be empty. Including them in this
project eliminates the need to drain the tank a second time, saving both time and money. 
(4) Including the additional scope items will fulfill requirements set by the Washington
Administrative Code regarding storage requirements and sampling ports for water quality
monitoring. 
Cons: 
(1)   Incur additional capital cost. 
This is the recommended alternative. 

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

             COMMISSION AGENDA – Action Item No. 8f                                   Page 4 of 4 
Meeting Date: April 16, 2024 
FINANCIAL IMPLICATIONS 
Cost Estimate/Authorization Summary               Capital        Expense           Total 
COST ESTIMATE 
Original estimate – Status 2 Budget               $1,572,000              $0      $1,572,000 
Previous changes – 5/24/22 Design Auth          $1,571,000        $26,000     $1,597,000 
Current change                                          $0              $0              $0 
Current estimate                                $3,143,000        $26,000     $3,169,000 
AUTHORIZATION 
Previous authorizations                           $1,124,000         $26,000      $1,150,000 
Current request for authorization                 $2,019,000              $0     $2,019,000 
Total authorization, including this request         $3,143,000         $26,000      $3,169,000 
Remaining amount to be authorized                     $0             $0             $0 
Annual Budget Status and Source of Funds 
The Water Reservoir Rehabilitation (C801172) is included in the 2024-2028 capital budget and
plan of finance with a budget of $3,143,000. The funding source would be Airport Development
Fund. 
Financial Analysis and Summary 
Project cost for analysis              $3,169,000 
Business Unit (BU)                  AV Division wide 
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                       $0.01 in 2026 
Future Revenues and Expenses (Total cost of ownership) 
Not applicable. 
ATTACHMENTS TO THIS REQUEST 
(1)   Presentation 
PREVIOUS COMMISSION ACTIONS OR BRIEFINGS 
May 24, 2022 – The Commission authorized the Executive Director to design and prepare
construction documents for the Water Reservoir Rehabilitation project in the amount of
$1,000,000. 

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