B67/100
MASON, CITY OF — Water Quality Report 2026
Serving 8,252 people · Michigan
Water Source
Groundwater
County
—
System ID
MI0004170
Violations
10
Contaminant Test Results
2 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Copper (90th percentile) | 1.39 mg/L | 1.30 mg/L | Over Limit |
Lead (90th percentile) | 0.002 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
5
Violations (last 5yr)
0
Unresolved
0
Health-Related
TIER 3Resolved
Surface water treatment technique failure
When: July 1, 2023 – November 30, 2023Enforcement: Resolving — corrective action underway
TIER 3Resolved
Failed Level 2 Assessment under Revised Total Coliform Rule
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: January 1, 2023 – December 31, 2023Rule: Stage 2 DBPREnforcement: Resolving — corrective action underway
TIER 3Resolved
Failed Level 2 Assessment under Revised Total Coliform Rule
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: January 1, 2023 – December 31, 2023Rule: Stage 2 DBPREnforcement: Resolving — corrective action underway
TIER 3Resolved
Exceeded the MCL for disinfection byproducts
This is a paperwork/process violation — it does not mean a contaminant was detected at unsafe levels.
When: January 1, 2022 – March 31, 2022Enforcement: Resolving — corrective action underway
TIER 3Resolved
Surface water treatment technique failure
When: July 1, 2021 – August 6, 2021Enforcement: Resolving — corrective action underway
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Frequently Asked Questions About MASON, CITY OF
Is MASON, CITY OF water safe to drink?
MASON, CITY OF water receives a grade of B (67/100), which is considered good. Out of 32 contaminants tested, 1 exceed EPA legal limits. 2 contaminant(s) exceed non-enforceable health goals. The water meets federal safety standards.
What contaminants has MASON, CITY OF detected?
32 contaminants were tested in MASON, CITY OF's water. Notable contaminants include Copper (90th percentile), Lead (90th percentile). 1 exceed EPA legal limits (MCLs). 2 exceed EPA health goals (MCLGs).
Does MASON, CITY OF have any EPA violations?
Yes, MASON, CITY OF has 10 EPA violation(s) on record, with the most recent in 2023. Violation types include Other, MR, MCL. 3 are health-based violations.
How many people does MASON, CITY OF serve?
MASON, CITY OF serves approximately 8,252 people, Michigan. The system provides water to 1 community: Mason.
What type of water does MASON, CITY OF provide?
MASON, CITY OF sources its water from groundwater. Groundwater is pumped from underground aquifers, which often provides natural filtration. The utility's system ID is MI0004170.
How does MASON, CITY OF compare to other utilities in Michigan?
MASON, CITY OF scores 67/100 with a grade of B (good). This is an above-average performance for utilities statewide. Visit our Michigan state page for a full comparison of water systems.