Old Lewisboro Elementary School
PWSID: NY5907702
This system currently has unresolved violations for: 5000. These violations mean contaminant levels exceeded EPA limits or required treatment was not performed.
This system has more violations on record than 97% of water systems in New York.
Violation trend: 29.6 per year over the last 5 years, up from 2.6 per year in the previous 5.
System Details
| Population Served | 50 |
| Service Connections | 1 |
| Water Source | Groundwater |
| System Type | Non-Transient Non-Community |
| Owner | Local Government |
| Status | Active |
| City | Katonah |
| EPA ZIP on File | 10536 |
| Note | School or Daycare |
Areas Served
- Westchester County
Lead & Copper Testing
| Contaminant | Level | EPA Action Level | Status |
|---|---|---|---|
| Lead (90th percentile) | 0.0119 mg/L | 0.015 mg/L | Below Action Level |
| Lead (90th percentile) | 0.0070 mg/L | 0.015 mg/L | Below Action Level |
| Lead (90th percentile) | 0.0040 mg/L | 0.015 mg/L | Below Action Level |
| Lead (90th percentile) | 0.0034 mg/L | 0.015 mg/L | Below Action Level |
| Lead (90th percentile) | 0.0030 mg/L | 0.015 mg/L | Below Action Level |
| Lead (90th percentile) | 0.0030 mg/L | 0.015 mg/L | Below Action Level |
| Lead (90th percentile) | 0.0029 mg/L | 0.015 mg/L | Below Action Level |
| Lead (90th percentile) | 0.0010 mg/L | 0.015 mg/L | Below Action Level |
1 Active Violations
| Contaminant | Violation | Date | Health-Based | Status |
|---|---|---|---|---|
| 5000 | TT | 2003-09-01 | Yes | Open |
Violation History (167 total)
| Contaminant | Violation | Date | Health-Based | Status |
|---|---|---|---|---|
| 1017 | MCL Measured: 328.00 MG/L (limit: 250.00 MG/L) | 2025-07-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 0.000015 MG/L (limit: 0.000010 MG/L) | 2025-07-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 0.000025 MG/L (limit: 0.000010 MG/L) | 2025-07-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 0.000109 MG/L (limit: 0.000010 MG/L) | 2025-07-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 0.000062 MG/L (limit: 0.000010 MG/L) | 2025-07-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 0.000018 MG/L (limit: 0.000010 MG/L) | 2025-07-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 0.000017 MG/L (limit: 0.000010 MG/L) | 2025-07-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 0.000012 MG/L (limit: 0.000010 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 0.000012 MG/L (limit: 0.000010 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 0.000017 MG/L (limit: 0.000010 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 0.000017 MG/L (limit: 0.000010 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 0.000110 MG/L (limit: 0.000010 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 0.000110 MG/L (limit: 0.000010 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 0.000047 MG/L (limit: 0.000010 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 0.000047 MG/L (limit: 0.000010 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 0.000018 MG/L (limit: 0.000010 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 0.000018 MG/L (limit: 0.000010 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 0.000012 MG/L (limit: 0.000010 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 0.000012 MG/L (limit: 0.000010 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 1017 | MCL Measured: 319.00 MG/L (limit: 250.00 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 1017 | MCL Measured: 319.00 MG/L (limit: 250.00 MG/L) | 2025-04-01 | Yes | Acknowledged |
| 1017 | MCL Measured: 342.00 MG/L (limit: 250.00 MG/L) | 2025-01-01 | Yes | Acknowledged |
| 1017 | MCL Measured: 342.00 MG/L (limit: 250.00 MG/L) | 2025-01-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 10.85 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 10.85 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 10.85 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 13.85 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 13.85 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 13.85 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 86.15 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 86.15 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 86.15 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 41.15 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 41.15 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 41.15 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 16.80 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 16.80 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 16.80 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 13.60 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 13.60 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 13.60 NG/L (limit: 10.00 NG/L) | 2025-01-01 | Yes | Acknowledged |
| 1017 | MCL Measured: 344.00 MG/L (limit: 250.00 MG/L) | 2024-10-01 | Yes | Acknowledged |
| 1017 | MCL Measured: 344.00 MG/L (limit: 250.00 MG/L) | 2024-10-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 0.000012 MG/L (limit: 0.000010 MG/L) | 2024-10-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 0.000017 MG/L (limit: 0.000010 MG/L) | 2024-10-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 0.000087 MG/L (limit: 0.000010 MG/L) | 2024-10-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 0.000040 MG/L (limit: 0.000010 MG/L) | 2024-10-01 | Yes | Acknowledged |
| 2805 | MCL Measured: 0.000018 MG/L (limit: 0.000010 MG/L) | 2024-10-01 | Yes | Acknowledged |
| 2806 | MCL Measured: 0.000014 MG/L (limit: 0.000010 MG/L) | 2024-10-01 | Yes | Acknowledged |
| 1017 | MCL Measured: 308.00 MG/L (limit: 250.00 MG/L) | 2024-07-01 | Yes | Acknowledged |
Showing 50 of 166 historical violations.
Understanding This Water System's Record
Old Lewisboro Elementary School is a non-transient non-community water system that draws from groundwater sources and serves a population of 50 in Katonah, New York. This page shows its complete compliance history as reported to the EPA's Safe Drinking Water Information System (SDWIS), the federal database that tracks every public water system in the United States.
What Do These Violations Mean?
Health-based violations mean the system exceeded an EPA maximum contaminant level (MCL) or failed to provide required treatment. These indicate potential health risks from contaminants like lead, arsenic, bacteria, nitrates, or disinfection byproducts. Non-health-based violations involve monitoring, reporting, or procedural requirements — the system missed a testing deadline or failed to notify customers, but contaminant levels were not necessarily unsafe.
What Should You Do?
Your water utility is required to publish an annual Consumer Confidence Report (CCR) that details test results and any violations. If your system has active health-based violations, consider a certified water filter rated for the specific contaminants involved. The contaminant guides on this site explain health risks and filter options for common pollutants. For the most current results, contact your water utility directly — EPA data can lag weeks or months behind real-time testing.