Public water system record
Flat Rock
Serves Flat Rock, Wayne County and Monroe County, MI · 10,541 people served
Federal records show 2 health-based violations and 2 monitoring/reporting issues for Flat Rock in the last ten years. The most serious issue in this window was a Surface Water Treatment Rule violation that EPA lists as archived, not resolved.
System profile
- Health-based violations, last 10 years
- 2
- Resolved
- 1
- Unresolved
- 0
- Archived by EPA
- 1
- Any acute record
- No
- Monitoring issues, last 10 years
- 2
Key facts
- Flat Rock buys its water from Great Lakes Water Authority.
- Lead pipe inventory: 178 lead and 12 unknown out of 2,997 service lines.
Check whether Flat Rock serves your address
Health-based violations
Since October 2016Violation data reflects EPA records through March 2026. For the most current status, visit the EPA ECHO database.
| Contaminant | Rule family | Start date | Status | Acute |
|---|---|---|---|---|
|
Surface Water Treatment Rule
Treatment technique failure
|
120 | Aug 1, 2025 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
No |
|
Surface Water Treatment Rule
Treatment technique failure
|
120 | Aug 1, 2022 | Resolved | No |
Monitoring and reporting issues
Since October 2016Missed tests or reports, not contaminants found above a limit.
| Issue | Start date | Status |
|---|---|---|
|
Haloacetic Acids (HAA5)
Monitoring and reporting
|
Oct 1, 2020 | Resolved |
|
Total Trihalomethanes (TTHMs)
Monitoring and reporting
|
Oct 1, 2020 | Resolved |
What the violations mean
Surface Water Treatment Rule
2 incidentsThe system did not complete a treatment step or action that the Surface Water Treatment Rule requires (a treatment technique violation).
The utility had to notify customers about each of these violations.
Where the water comes from
Flat Rock buys its water from Great Lakes Water Authority. It lists no wells or intakes of its own.
Buys water from
- Great Lakes Water Authority Detroit, MI
Annual water quality report
Flat Rock must give its customers an annual water quality report (Consumer Confidence Report) by July 1, with the levels its tests found in the previous year.
Systems serving 10,000 or more people must mail or deliver the report to every customer, and from 2027 they must send it twice a year.
Find a posted report with EPA's Consumer Confidence Report search
Testing your own water
To test the water at your tap, or a private well this record does not cover, use a laboratory certified for drinking water by Michigan.
Certified drinking water labs by state EPA guidance for private wells