Seattle Public Utilities
EPA ID: WA5377050 · 1,161,961 people served · 32 ZIP codes
ZipCheckup's reading of EPA records for Seattle Public Utilities (WA5377050): no drinking-water violations recorded since 2021. Across the monitored periods in available EPA data, Seattle Public Utilities has no violations listed for its service population of 1,161,961.
Data: EPA SDWIS
Service Area Map
Coverage area for Seattle Public Utilities Source: EPA SDWIS service area boundaries.
Service area boundary - average Home Safety grade of mapped ZIPs: A
Demographics of ZIP Codes Served
The ZIP codes associated with Seattle Public Utilities have a median household income of $114,962 and about 917,175 residents live in those ZIP codes (Census; not the number of people this system supplies). Approximately 64% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
🌊 Where Does Your Water Come From?
Seattle Public Utilities's water is drawn from rivers, lakes, or reservoirs. Surface water sources are more exposed to agricultural runoff, stormwater, and upstream discharges, but they typically receive more intensive treatment before reaching your tap.
Superfund Proximity Note: This service area ranks in the 69th percentile nationally for proximity to Superfund (NPL) sites.
Infrastructure Risk
PFAS in ZIP Codes This System Serves
PFAS ("forever chemicals") have been reported in samples from water systems associated with the ZIP codes in this system's area. These results can come from other water systems serving the same ZIP codes; check the UCMR5 section for any results reported for this system. 1 detection recorded.
Comparable Water Systems
Similar-sized systems in Washington
Estimated Remediation Costs
Average estimated costs across ZIP codes served by this system
Based on national averages for common remediation projects. Actual costs vary by property. Only issues flagged by EPA, FEMA, or state data for each ZIP code are included.
System Overview
Seattle Public Utilities (EPA ID: WA5377050) is a community water system in Washington that serves approximately 1,161,961 people from surface water sources.
This system provides water to 32 ZIP codes across 1 community.
ZIP-Area Home Safety Context: A (100/100)
This is the average Home Safety Score for 27 of 32 service-area ZIP codes with all required score domains observed. It is not a grade for the water utility.
Model 4.0.0 uses SDWIS identity plus accepted ECHO SDWA lifecycle-based water compliance, the UCMR 5 PFAS MCL screen, EPA radon zone, and annual EPA AirData AQI across three equally weighted domains. Missing required evidence suppresses the score.
Violation History
Lead & Copper
EPA Lead and Copper Rule evidence attributed directly to this water system:
| Lead Level | Exceeds Action Level | Sample Date |
|---|---|---|
| 0.0016 mg/L | No | 2025-12-31 |
No copper action-level exceedance record appears for this PWSID in the accepted LCR snapshot. This does not establish a clean copper measurement.
Radon Risk in Service Area
32 of 32 ZIP records with known zones are in EPA Radon Zone 3.
The EPA recommends testing all homes regardless of radon zone. County radon zones cannot replace an in-home radon test.
ZIP Codes Served
Coverage: Service area ZIP codes sourced from EPA Community Water System Service Area Boundaries v3 (March 2026 release). These ZIPs reflect the actual deployment footprint recorded by WA or modeled from parcel and building-footprint data.
This system serves 32 ZIP codes:
98101 · 98102 · 98103 · 98104 · 98105 98106 · 98107 · 98108 · 98109 · 98112 98115 · 98116 · 98117 · 98118 · 98119 98121 · 98122 · 98125 · 98126 · 98133 98134 · 98136 · 98144 · 98146 · 98155 98166 · 98168 · 98174 · 98177 · 98178 98195 · 98199
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View available EPA compliance records for Seattle Public Utilities (WA5377050) on EPA.gov.
Frequently Asked Questions
Is Seattle Public Utilities water safe to drink?
The accepted 2026Q2 ECHO snapshot contains zero violation records for Seattle Public Utilities in the inclusive 2021-2026 record-year window. This is a compliance-record finding, not a guarantee about water at a specific tap.
How many people does Seattle Public Utilities serve?
Seattle Public Utilities serves approximately 1,161,961 people across 32 ZIP codes in Washington.
Where does Seattle Public Utilities get its water?
The primary water source is surface water.
Federal UCMR5 PFAS Monitoring: No PFAS Reported Above Reporting Levels
This water system was tested under the federal EPA Unregulated Contaminant Monitoring Rule (UCMR5). No PFAS compounds were reported above UCMR5 minimum reporting levels.
EPA's April 2024 PFAS rule sets MCLs of 4 ppt for PFOA and PFOS and 10 ppt for PFHxS, PFNA and HFPO-DA (GenX); water systems must comply from 2029. Other PFAS compounds have no individual federal MCL. A state standard is shown only where this system's state has its own enforceable PFAS limit. Detection results are EPA UCMR5 samples, not a measurement at your tap.
Source: U.S. EPA UCMR5 (Unregulated Contaminant Monitoring Rule, 5th cycle) — per-system federal sampling, 2023–2025. EPA UCMR5 monitoring program →
Frequently Asked Questions
How to cite this page
ZipCheckup. (n.d.). Seattle Public Utilities, WA: Serves 1.2M People. https://zipcheckup.com/water-system/wa5377050/
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