Onamac Water System
EPA ID: WA5363907 · 177 people served · 1 ZIP code
Onamac Water System's five-year compliance history is clean by every EPA metric — no health-based violations, no monitoring lapses, no enforcement actions on record, reflecting consistent performance for a utility that supplies water to approximately 177 residents year after year.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for Onamac Water System Source: EPA SDWIS service area boundaries.
Service area boundary
Service Area Demographics
The Onamac Water System serves a community with a median household income of $100,124 and an estimated 17,535 residents across its service area.
💧 Where Does Your Water Come From?
Onamac Water System's water is pumped from underground aquifers. Groundwater is naturally filtered through rock and soil, but it can be vulnerable to PFAS contamination, nitrates from agriculture, and industrial chemicals that seep into the water table.
About 2% of homes in Island County, Washington rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Superfund Proximity Note: This service area ranks in the 60th percentile nationally for proximity to Superfund (NPL) sites. Groundwater sources near contaminated sites may face elevated risk from industrial chemicals.
Infrastructure Risk
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
Onamac Water System (EPA ID: WA5363907) is a community water system in Washington that serves approximately 177 people from groundwater sources.
This system serves ZIP code 98282 in Camano Island.
Violation History
Lead & Copper
No Lead and Copper Rule sampling data available for this water system.
Need help with your water quality?
Typical cost: Water test: typically $20–$50 (DIY kit) · Professional inspection: $150–$400
Find the Right Water FilterFree tip: Let cold water run for 2 minutes before drinking — this helps flush lead from your pipes.
ZIP Codes Served
- 98282 — Camano Island
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for Onamac Water System (WA5363907) on EPA.gov.
Frequently Asked Questions
Is Onamac Water System water safe to drink?
Based on EPA records, Onamac Water System has no recorded violations in the past 5 years — a positive indicator of water quality management.
How many people does Onamac Water System serve?
Onamac Water System serves approximately 177 people across 1 ZIP code in Washington.
Where does Onamac Water System get its water?
The primary water source is groundwater.
Lead Service Line Inventory
Service line breakdown reported under the federal Lead and Copper Rule Improvements (LCRI) inventory requirement:
This system reports zero confirmed lead service lines in its inventory. Unknown-material counts may still warrant verification.
Federal LCRI rule (effective October 2024) requires every public water system to inventory its service lines and complete lead-line replacement within 10 years.
Source: EPA SDWIS Federal Service Line Inventory (Phase 2) · Submitted 2026
ZipCheckup is not affiliated with the utility or state agency. Inventory figures render verbatim from the public LCRI submission cited above; ZipCheckup does not perform inspections or replacements.