City of Mackay
EPA ID: ID7190032 · 566 people served · 1 ZIP code
Although compliance varies widely among water utilities nationally, City of Mackay stands out with zero EPA violations over five consecutive monitoring years, delivering safe tap water to 566 residents and showing no enforcement activity across the entire reporting span.
Data: EPA SDWIS Last verified: 2026-04-02
Service Area Map
Coverage area for City of Mackay Source: EPA SDWIS service area boundaries.
Service area boundary — Grade B
Service Area Demographics
The City of Mackay serves a community with a median household income of $55,938 and an estimated 1,322 residents across its service area. Approximately 52% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
Environmental Justice Note: 100% of the population in this service area is classified as disadvantaged under EPA's EJScreen criteria. Communities with higher disadvantaged populations often face disproportionate environmental and health burdens, including aging water infrastructure and limited resources for remediation.
💧 Where Does Your Water Come From?
City of Mackay'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 0% of homes in Custer County, Idaho rely on private wells rather than public water systems. Private well owners are responsible for their own water testing and treatment.
Infrastructure Risk
Comparable Water Systems
Similar-sized systems in Idaho
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
City of Mackay (EPA ID: ID7190032) is a community water system in Idaho that serves approximately 566 people from groundwater sources.
This system serves ZIP code 83251 in Mackay.
Average Home Safety Score: B (70/100)
Based on water quality violations, lead levels, and radon risk across all ZIP codes served by this system.
Violation History
Lead & Copper
EPA Lead and Copper Rule sampling data for ZIP codes served by this system:
| ZIP Code | Lead Level | Exceeds Limit | Sample Date |
|---|---|---|---|
| 83251 | 0.001 mg/L | No | N/A |
Radon Risk in Service Area
Dominant radon zone for ZIP codes served by this system: Zone 1 (High Risk)
The EPA recommends testing homes in Zone 1 and Zone 2 areas for radon.
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
- 83251 — Mackay
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View the full compliance record for City of Mackay (ID7190032) on EPA.gov.
Frequently Asked Questions
Is City of Mackay water safe to drink?
Based on EPA records, City of Mackay has no recorded violations in the past 5 years — a positive indicator of water quality management.
How many people does City of Mackay serve?
City of Mackay serves approximately 566 people across 1 ZIP code in Idaho.
Where does City of Mackay 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.