Public water system · WA5303182
ActivePort of Seattle/Seatac Airport
At a glance
Port of Seattle/Seatac Airport (PWSID WA5303182) is an active non-transient non-community water system in King County, Washington. It reports serving 49,483 people through 146 service connections. Its primary water source is purchased surface water, and EPA lists it as owned by a local government. EPA's records list 6 violations for this system; 1 is health-based, and the most recent began in April 2015.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
49,483
Service connections
146
Primary source
SWP
Purchased surface water
System type
NTNCWS
Non-transient non-community water system
System record
How does Port of Seattle/Seatac Airport compare with other water systems in King County?
By EPA's size categories, Port of Seattle/Seatac Airport is a large system (10,001 to 100,000 people). King County has 214 active public water systems. Its population served is about 3.2 times the county average of 15,523 people per system, and accounts for 1.5% of the 3,321,960 people reported by systems filed under the county. Across Washington, the 4,705 active systems average 2,172 people each. Nationally, the average active non-transient non-community water system reports serving 430 people, so Port of Seattle/Seatac Airport is about 115 times that figure.
What does “non-transient non-community water system” mean?
A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. Washington has 400 active non-transient non-community water systems, 8.5% of the state's 4,705 active systems. Purchased surface water means the system buys surface water from another public water system rather than drawing its own. 130 Washington systems (2.8%) list purchased surface water as their primary source.
Who owns and regulates Port of Seattle/Seatac Airport?
EPA lists Port of Seattle/Seatac Airport as owned by a local government. The WA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 58 of the 214 active systems in King County (27%) are also owned by a local government.
Does Port of Seattle/Seatac Airport have drinking water violations?
EPA's records list 6 violations for this system; 1 is health-based, and the most recent began in April 2015. The violations listed here began between March 1994 and April 2015. By type: 5 monitoring and reporting and 1 contaminant level above the legal limit. The contaminant or rule involved most often is Lead and Copper Rule (2 of them). EPA lists 4 as resolved and 2 as archived. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2015-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Total trihalomethanes (TTHM)code 2950 | No | Resolved |
| 2015-04-01 | Monitoring and reportingMonitoring and Reporting (DBP) · code 27 | Haloacetic acids (HAA5)code 2456 | No | Resolved |
| 2005-01-01 | Monitoring and reportingFollow-up Or Routine LCR Tap M/R · code 52 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1997-07-01 | Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51 | Lead and Copper Rulecode 5000 | No | Resolved |
| 1994-05-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Archived |
| 1994-03-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Archived |
All 6 violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Port of Seattle/Seatac Airport: frequently asked questions
Who runs Port of Seattle/Seatac Airport?
Port of Seattle/Seatac Airport (PWSID WA5303182) is a non-transient non-community water system owned by a local government. It is regulated by the WA state drinking water program.
How many people does Port of Seattle/Seatac Airport serve?
Port of Seattle/Seatac Airport reports serving 49,483 people through 146 service connections in King County, Washington.
Where does Port of Seattle/Seatac Airport get its water?
EPA SDWIS lists this system's primary water source as purchased surface water. Purchased surface water means the system buys surface water from another public water system rather than drawing its own.
Does Port of Seattle/Seatac Airport have any drinking water violations?
EPA's records list 6 violations for this system; 1 is health-based, and the most recent began in April 2015. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Port of Seattle/Seatac Airport's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. EPA's records list 6 violations for this system; 1 is health-based, and the most recent began in April 2015. For current results, consult EPA ECHO, or the WA state drinking water program.
Where can I find Port of Seattle/Seatac Airport's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Port of Seattle/Seatac Airport is a non-transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in King County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Seattle Public Utilities | King | 1,161,961 | Community | Surface water |
| Bellevue City of | King | 321,349 | Community | Purchased surface water |
| Kent Water Department | King | 166,421 | Community | Purchased surface water |
| Redmond Water System City of | King | 163,335 | Community | Purchased surface water |
| Lakehaven Water and Sewer District | King | 148,809 | Community | Purchased surface water |
| Renton City of | King | 108,091 | Community | Groundwater |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Port of Seattle/Seatac Airport, PWSID WA5303182, Washington”, https://aquacensus.com/water-systems/washington/port-of-seattle-seatac-airport-wa5303182 (data as of October 1, 2026).