Usn San Clemente Island
Published drinking-water records and contacts for Usn San Clemente Island. System CA3710707. Review sources and dates; not a real-time water assessment.
- System ID
- CA3710707
- State or territory
- CA
- Published population served
- 800
- System type (source code)
- NTNCWS
Published records and dates
- Lead and copper monitoring summaries: 62 — 1993-01-01 – 2026-06-30
- California DDW laboratory results: 614 — 2026-01-06 – 2026-06-03
Missing records here do not mean the provider did not test. Published records are not a real-time assessment of your tap water.
Published testing results
Selected recent records are shown below. Different sampling locations and dates are not interchangeable. These excerpts are not a complete testing history.
“<” means below the stated reporting limit, not zero. A reported measurement alone is not a safety verdict. Read an example
Lead and copper: 90th-percentile summaries
These describe a monitoring period across sampled locations, not the result at your home. How to read the 90th percentile
| Substance | Published 90th percentile | Monitoring period | Source quarter |
|---|---|---|---|
| Lead (PB90) | 0 mg/L | 2026-01-01 – 2026-06-30 | 2026Q3 |
| Lead (PB90) | 0 mg/L | 2025-07-01 – 2025-12-31 | 2026Q3 |
| Lead (PB90) | 0.0022 mg/L | 2025-01-01 – 2025-06-30 | 2026Q3 |
| Lead (PB90) | 0.0884 mg/L | 2024-07-01 – 2024-12-31 | 2026Q3 |
| Lead (PB90) | 0.00182 mg/L | 2024-01-01 – 2024-06-30 | 2026Q3 |
| Lead (PB90) | 0.00211 mg/L | 2023-07-01 – 2023-12-31 | 2026Q3 |
| Lead (PB90) | 0.00211 mg/L | 2023-07-01 – 2023-12-31 | 2026Q3 |
| Lead (PB90) | 0.00127 mg/L | 2023-01-01 – 2023-06-30 | 2026Q3 |
| Substance | Published result | Sample date | Location / source |
|---|---|---|---|
| DICHLOROACETIC ACID | < 1.000000000 UG/L | 2026-06-03 | DBPR Sample / California DDW laboratory results |
| BROMOFORM | 4.6 UG/L | 2026-06-03 | DBPR Sample / California DDW laboratory results |
| MONOCHLOROACETIC ACID | < 2.000000000 UG/L | 2026-06-03 | DBPR Sample / California DDW laboratory results |
| DIBROMOACETIC ACID | 1.1 UG/L | 2026-06-03 | DBPR Sample / California DDW laboratory results |
| MONOBROMOACETIC ACID | < 1.000000000 UG/L | 2026-06-03 | DBPR Sample / California DDW laboratory results |
| DIBROMOCHLOROMETHANE | 2.8 UG/L | 2026-06-03 | DBPR Sample / California DDW laboratory results |
| TOTAL HALOACETIC ACIDS (HAA5) | < 2.000000000 UG/L | 2026-06-03 | DBPR Sample / California DDW laboratory results |
| TRICHLOROACETIC ACID | < 1.000000000 UG/L | 2026-06-03 | DBPR Sample / California DDW laboratory results |
| CHLOROFORM | 0.84 UG/L | 2026-06-03 | DBPR Sample / California DDW laboratory results |
| TTHM | 9.8 UG/L | 2026-06-03 | DBPR Sample / California DDW laboratory results |
| BROMODICHLOROMETHANE | 1.6 UG/L | 2026-06-03 | DBPR Sample / California DDW laboratory results |
| MONOBROMOACETIC ACID | 1.6 UG/L | 2026-06-02 | DBPR Sample / California DDW laboratory results |
State sampling points can include untreated water. Publisher qualifiers and units are retained; consult the full source notes before interpreting a record.
Download state records with source notes (CSV)
Published compliance history
11 imported records. Status is as recorded in the source; historical records are not current advisories. Missing records do not establish that no violations occurred.
| Rule / record | Period | Recorded status | Health-based (EPA classification) | Source quarter |
|---|---|---|---|---|
| Revised Total Coliform Rule / Monitoring, Routine (RTCR) | 2025-06-01 – 2025-06-30 | Archived | No | 2026Q3 |
| Revised Total Coliform Rule / Monitoring, Routine (RTCR) | 2025-03-01 – 2025-03-31 | Archived | No | 2026Q3 |
| Surface Water Treatment Rule / Treatment Technique (SWTR and GWR) | 2025-02-01 – 2025-02-28 | Archived | Yes | 2026Q3 |
| Stage 2 Disinfectants and Disinfection Byproducts Rule / Maximum Contaminant Level Violation, Average | 2025-01-01 – 2025-03-31 | Archived | Yes | 2026Q3 |
| Surface Water Treatment Rule / Treatment Technique (SWTR and GWR) | 2024-11-01 – 2024-11-30 | Archived | Yes | 2026Q3 |
| Stage 2 Disinfectants and Disinfection Byproducts Rule / Maximum Contaminant Level Violation, Average | 2024-10-01 – 2024-12-31 | Archived | Yes | 2026Q3 |
| Surface Water Treatment Rule / Treatment Technique (SWTR and GWR) | 2024-09-01 – 2024-09-30 | Archived | Yes | 2026Q3 |
| Stage 2 Disinfectants and Disinfection Byproducts Rule / Maximum Contaminant Level Violation, Average | 2024-07-01 – 2024-09-30 | Archived | Yes | 2026Q3 |
| Stage 2 Disinfectants and Disinfection Byproducts Rule / Maximum Contaminant Level Violation, Average | 2024-04-01 – 2024-06-30 | Archived | Yes | 2026Q3 |
| Surface Water Treatment Rule / Treatment Technique (SWTR and GWR) | 2024-04-01 – 2024-04-30 | Archived | Yes | 2026Q3 |
| Miscellaneous Other Rules / Operations Report | 2012-10-01 – 2013-03-08 | Archived | No | 2026Q3 |
Source dates and refresh checks
A refresh check is not a sample date. Publication periods, sample dates and checks are shown separately.
- EPA SDWIS lead/copper summaries and service areas — source period: — – —; last checked: 2026-10-17
- EPA SDWIS contacts and compliance records — source period: — – —; last checked: 2026-10-17
- EPA UCMR 5 sample results — source period: 2023-01-03 – 2026-06-17; last checked: 2026-10-17
- California DDW laboratory results — last successful check: 2026-10-17
Administrative contact (EPA filing)
Nguyen, Victoria: 619-545-1127
An administrative filing contact may not be a customer-service line. Confirm current contact details with the provider.