Snow Storage Expansion Phase II
Construction Authorization
CIP# C801171
Seattle-Tacoma
International Airport
8c_supp
Item No.
October 28, 2025Date of Meeting
Action Requested
Request Commission authorization for the Executive Director to
advertise and execute a construction contract for Snow Storage
Expansion Phase II (CIP# C801171) adjacent to the Industrial
Wastewater System (IWS) Lagoon 3.
The total request for this action will be $14,403,000 for a total
project authorization to date of $24,800,000. The estimated overall
cost of the project is $24,800,000.
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This project is needed to meet regulatory requirements and
operational demands for airfield snow management.
• Provide additional snow storage capacity connected to the
Industrial Wastewater System (IWS)
• Historical excess snow storage areas are now occupied by Cargo/Remaining Overnight
(RON) aircrafts
• Snow storage capacity at completion of the project: 12” precipitation event
• All snow melt areas will be connected to IWS to ensure compliance with National
Pollutant Discharge Elimination Systems (NPDES) Permit Compliance
• Increase operational safety for snow operations vehicles
• Reduce operational expenses from rehandling snow
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Project Overview
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Project Scope
• Phase I – Completed in 2023
– North Snow Storage Area
– Expand existing asphalt pad and upgrade the IWS Pump Station
– South Snow Storage Area
– Expand existing truck turnaround for maneuverability and safety
– Vehicle Service Road (south and west of RW 16L/34R)
– Widen asphalt road for snow removal vehicle safety
• Phase II - 2026 Construction
– Construct New Snow Storage Area adjacent to IWS Lagoon 3
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Snow Storage Expansion Sites
Construction Schedule
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• Phase II
– Commission Authorization for Construction Q4 2025
– Issue Notice to Proceed: Q2 2026
– In-Service Q4 2026
Budget
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Total ProgramThis RequestSnow Storage Expansion
Project (C801171)
$2,500,000$0Design
$22,300,000$14,403,000Construction
$24,800,000$14,403,000Total
Project Risks
MITIGATION PLANIMPACTPROBLEMDESCRIPTIONRISK
Include additional time in
schedule for weather risks.
MedLow Construction may be impacted by
inclement weather.
Weather Delay
Use historical pricing with
thoughtful adjustment for
current market conditions.
Include contingency in the
estimate.
HighMedMarket conditions may change
and result in bids exceeding Port
estimate.
Increased Cost
Implement monitoring and
action plan for construction for
possible discoveries.
HighMedPossible conditions include:
• Buried debris
• Archaeological
• Unsuitable soil conditions
Unforeseen Site
Conditions
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Project Opportunities
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• Support other program scopes and schedules
• Airfield Pavement and Supporting Infrastructure Replacement Program
• Perimeter Intrusion detection System (PIDS)
• Reduce project impacts, schedule and safety risks by avoiding
construction in the winter season.
Operated by the
Port of Seattle
FlySEA.org
Thank
You!
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