MacKaye Harbor Water District
EPA ID: WA5312911 · 133 people served · 1 ZIP code
MacKaye Harbor Water District's record shows 1 remedied violation — all cleared, currently compliant, 133 residents.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for MacKaye Harbor Water District Source: EPA SDWIS service area boundaries.
Service area boundary — Grade A
Service Area Demographics
The MacKaye Harbor Water District serves a community with a median household income of $78,871 and an estimated 3,030 residents across its service area. Approximately 51% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
💧 Where Does Your Water Come From?
MacKaye Harbor Water District'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 3% of homes in San Juan County, Washington rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Infrastructure Risk
Detected Contaminants
How MacKaye Harbor Water District compares to EPA limits
What This Means For You
Surface Water Treatment Rule at 1 mg/L exceeds the EPA maximum of mg/L.
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
MacKaye Harbor Water District (EPA ID: WA5312911) is a community water system in Washington that serves approximately 133 people from groundwater sources.
This system serves ZIP code 98261 in Lopez Island.
Average Home Safety Score: A (95/100)
Based on water quality violations, lead levels, and radon risk across all ZIP codes served by this system.
Violation History
Contaminants Detected
The following contaminants have been flagged in EPA records for this water system:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| Surface Water Treatment Rule | Treatment Failure | 1 | No |
Lead & Copper
EPA Lead and Copper Rule sampling data for ZIP codes served by this system:
| ZIP Code | Lead Level | Exceeds Limit | Sample Date |
|---|---|---|---|
| 98261 | 0.0024 mg/L | No | N/A |
Radon Risk in Service Area
Dominant radon zone for ZIP codes served by this system: Zone 3 (Low Risk)
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
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.
- 98261 — Lopez Island
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for MacKaye Harbor Water District (WA5312911) on EPA.gov.
Frequently Asked Questions
Is MacKaye Harbor Water District water safe to drink?
MacKaye Harbor Water District has only monitoring/reporting violations, which are procedural in nature. The system meets federal health-based standards.
How many people does MacKaye Harbor Water District serve?
MacKaye Harbor Water District serves approximately 133 people across 1 ZIP code in Washington.
Where does MacKaye Harbor Water District get its water?
The primary water source is groundwater.
Frequently Asked Questions
What You Can Do
Test your water
Home test kits can detect lead, bacteria, and other contaminants at your tap. Find the right filter →
Check your specific ZIP code
Water quality can vary within a system. View nearest ZIP report →
Contact your utility
MacKaye Harbor Water District (EPA ID: WA5312911) — request the latest Consumer Confidence Report or ask about specific contaminants.