Improvement District No. 1
Published drinking-water records and contacts for Improvement District No. 1. System CA5400968. Review sources and dates; not a real-time water assessment.
- System ID
- CA5400968
- State or territory
- CA
- Published population served
- 200
- System type (source code)
- CWS
Published records and dates
- Lead and copper monitoring summaries: 12 — 1996-07-01 – 2026-12-31
- California DDW laboratory results: 148 — 2026-02-11 – 2026-06-26
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 | 2024-01-01 – 2026-12-31 | 2026Q3 |
| Lead (PB90) | 0 mg/L | 2021-01-01 – 2023-12-31 | 2026Q3 |
| Lead (PB90) | 0 mg/L | 2018-01-01 – 2020-12-31 | 2026Q3 |
| Lead (PB90) | 0 mg/L | 2015-01-01 – 2017-12-31 | 2026Q3 |
| Lead (PB90) | 0 mg/L | 2012-01-01 – 2014-12-31 | 2026Q3 |
| Lead (PB90) | 0.00165 mg/L | 2007-01-01 – 2009-12-31 | 2026Q3 |
| Lead (PB90) | 0.0111 mg/L | 2004-01-01 – 2006-12-31 | 2026Q3 |
| Lead (PB90) | 0.007 mg/L | 2001-01-01 – 2003-12-31 | 2026Q3 |
| Substance | Published result | Sample date | Location / source |
|---|---|---|---|
| ALUMINUM | 66 UG/L | 2026-06-26 | WELL 05 (RIVER WELL-IG) - RAW / California DDW laboratory results |
| 1,2-DICHLOROPROPANE | < 0.500000000 UG/L | 2026-06-26 | WELL 05 (RIVER WELL-IG) - RAW / California DDW laboratory results |
| 1,1,1-TRICHLOROETHANE | < 0.500000000 UG/L | 2026-06-26 | WELL 05 (RIVER WELL-IG) - RAW / California DDW laboratory results |
| PERFLUOROPENTANESULFONIC ACID (PFPES) | < 2.000000000 NG/L | 2026-06-26 | WELL 05 (RIVER WELL-IG) - RAW / California DDW laboratory results |
| DIBROMOCHLOROMETHANE | < 1.000000000 UG/L | 2026-06-26 | WELL 05 (RIVER WELL-IG) - RAW / California DDW laboratory results |
| TRICHLOROTRIFLUOROETHANE | < 10.000000000 UG/L | 2026-06-26 | WELL 05 (RIVER WELL-IG) - RAW / California DDW laboratory results |
| TURBIDITY | 1.2 NTU | 2026-06-26 | WELL 05 (RIVER WELL-IG) - RAW / California DDW laboratory results |
| 1,3-DICHLOROPROPENE | < 0.500000000 UG/L | 2026-06-26 | WELL 05 (RIVER WELL-IG) - RAW / California DDW laboratory results |
| POTASSIUM | < 1.000000000 MG/L | 2026-06-26 | WELL 05 (RIVER WELL-IG) - RAW / California DDW laboratory results |
| HFPO-DA | < 2.000000000 NG/L | 2026-06-26 | WELL 01 (WAGONWHEEL-GWUDI) - RAW / California DDW laboratory results |
| PERFLUOROHEXANE SULFONIC ACID (PFHxS) | < 2.000000000 NG/L | 2026-06-26 | WELL 05 (RIVER WELL-IG) - RAW / California DDW laboratory results |
| NONAFLUORO NFDHA | < 2.000000000 NG/L | 2026-06-26 | WELL 01 (WAGONWHEEL-GWUDI) - RAW / 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
30 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 |
|---|---|---|---|---|
| Stage 2 Disinfectants and Disinfection Byproducts Rule / Monitoring and Reporting (DBP) | 2025-06-01 – 2025-06-30 | Archived | No | 2026Q3 |
| Stage 2 Disinfectants and Disinfection Byproducts Rule / Monitoring and Reporting (DBP) | 2025-06-01 – 2025-06-30 | Archived | No | 2026Q3 |
| Revised Total Coliform Rule / Monitoring, Routine (RTCR) | 2019-09-01 – 2019-09-30 | Resolved | No | 2026Q3 |
| Nitrate Rule / Monitoring, Regular | 2017-01-01 – 2017-12-31 | Resolved | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1984-09-01 – 1984-09-30 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1984-08-01 – 1984-08-31 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1984-07-01 – 1984-07-31 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1984-06-01 – 1984-06-30 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1984-05-01 – 1984-05-31 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1984-04-01 – 1984-04-30 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1984-03-01 – 1984-03-31 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1984-02-01 – 1984-02-29 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1984-01-01 – 1984-01-31 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1983-12-01 – 1983-12-31 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1983-11-01 – 1983-11-30 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1983-10-01 – 1983-10-31 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1983-09-01 – 1983-09-30 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1983-08-01 – 1983-08-31 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1983-07-01 – 1983-07-31 | Archived | No | 2026Q3 |
| Miscellaneous Other Rules / Notification, Public | 1983-06-01 – 1983-06-30 | 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: 2026-10-18
Administrative contact (EPA filing)
Brunson, Nancy: 559-561-2222
An administrative filing contact may not be a customer-service line. Confirm current contact details with the provider.