Markham
PWSID: IL0311770
System Details
| Population Served | 12,500 |
| Service Connections | 4,138 |
| Water Source | Surface Water Purchased |
| System Type | Community Water System |
| Owner | Local Government |
| Status | Active |
| City | Markham |
| Zip Code | 60428 |
Lead & Copper Testing
| Contaminant | Level | EPA Action Level | Status |
|---|
| Lead (90th percentile) | 0.0030 mg/L | 0.015 mg/L | Below Action Level |
| Lead (90th percentile) | 0.0026 mg/L | 0.015 mg/L | Below Action Level |
| Lead (90th percentile) | 0.0024 mg/L | 0.015 mg/L | Below Action Level |
| Lead (90th percentile) | 0.0021 mg/L | 0.015 mg/L | Below Action Level |
2 Active Violations
| Contaminant | Violation | Date | Health-Based | Status |
|---|
| | 2025-07-02 | | Open |
| | 2025-07-01 | | Open |
Violation History (20 total)
| Contaminant | Violation | Date | Health-Based | Status |
|---|
| | 2025-07-01 | Major | Acknowledged |
| | 2023-07-01 | | Returned to Compliance |
| | 2023-07-01 | | Returned to Compliance |
| | 2023-06-15 | | Returned to Compliance |
| | 2023-06-15 | | Returned to Compliance |
| | 2023-06-15 | | Returned to Compliance |
| | 2023-06-15 | | Returned to Compliance |
| | 2022-05-01 | | Returned to Compliance |
| | 2022-05-01 | | Returned to Compliance |
| | 2022-05-01 | | Returned to Compliance |
| | 2022-04-01 | Major | Returned to Compliance |
| | 2022-04-01 | Major | Returned to Compliance |
| | 2022-04-01 | Major | Returned to Compliance |
| | 2022-04-01 | Major | Returned to Compliance |
| | 2020-12-30 | | Returned to Compliance |
| | 2011-07-01 | | Returned to Compliance |
| | 1996-10-01 | | Returned to Compliance |
| | 1994-10-01 | | Returned to Compliance |