Public water system record
Rancho San Joaquin MWC
Serves an area of San Benito County, CA · 914 people served
Federal records show 3 health-based violations and 7 monitoring/reporting issues for Rancho San Joaquin MWC in the last ten years, including an unresolved LEAD AND COPPER RULE REVISIONS violation.
System profile
- Health-based violations, last 10 years
- 3
- Resolved
- 0
- Unresolved
- 1
- Archived by EPA
- 2
- Any acute record
- No
- Monitoring issues, last 10 years
- 7
Key facts
- Rancho San Joaquin MWC draws water from 1 well.
- Highest measured level in the last 10 years: Arsenic, 0.023 mg/L, federal limit 0.01 mg/L (2.3 times the limit), 2023.
- Most recent formal enforcement: compliance order with a penalty by California, September 2024.
- Record on file since 1996, with 3 health-based violations before October 19, 2016.
- Lead pipe inventory: 0 lead and 0 unknown out of 32 service lines.
Check whether Rancho San Joaquin MWC 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 |
|---|---|---|---|---|
|
LEAD AND COPPER RULE REVISIONS
Treatment technique failure
|
350 | Oct 17, 2024 | Active | No |
|
Arsenic
Contaminant limit exceeded
Measured 0.023 mg/L, federal limit 0.01 mg/L (2.3 times the limit)
|
330 | Jul 1, 2023 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
No |
|
Arsenic
Contaminant limit exceeded
Measured 0.011 mg/L, federal limit 0.01 mg/L (1.1 times the limit)
|
330 | Oct 1, 2022 |
Archived
Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
|
No |
Monitoring and reporting issues
Since October 2016Missed tests or reports, not contaminants found above a limit.
| Issue | Start date | Status |
|---|---|---|
|
LEAD AND COPPER RULE REVISIONS
RPT
|
Oct 17, 2024 | Active |
|
Public Notice
OTHER
|
Apr 1, 2024 | Resolved |
|
Total Trihalomethanes (TTHMs)
Monitoring and reporting
|
Jan 1, 2021 | Resolved |
|
Haloacetic Acids (HAA5)
Monitoring and reporting
|
Jan 1, 2021 | Resolved |
|
Revised Total Coliform Rule
Monitoring violation
|
Feb 1, 2018 | Resolved |
|
Lead and Copper Rule
Monitoring and reporting
|
Oct 1, 2017 | Resolved |
|
Lead and Copper Rule
Monitoring and reporting
|
Oct 1, 2017 | Resolved |
Full record since 1996
EPA's records for Rancho San Joaquin MWC go back to 1996. Before October 19, 2016 they list 3 health-based violations (3 resolved) and 9 monitoring or reporting violations.
| Violations that began in | Health-based | Monitoring and reporting |
|---|---|---|
| 1990s | 3 | 0 |
| 2000s | 0 | 5 |
| 2010 to October 18, 2016 | 0 | 4 |
| October 19, 2016 to 2019 | 0 | 3 |
| 2020s | 3 | 4 |
Most recent health-based violation before October 19, 2016: Total Coliform, began August 1997, Resolved.
Show all 3 health-based violations before October 19, 2016
| Contaminant | Start date | Status |
|---|---|---|
|
Total Coliform
Contaminant limit exceeded
|
Aug 1, 1997 | Resolved |
|
Total Coliform
Contaminant limit exceeded
|
Oct 1, 1996 | Resolved |
|
Total Coliform
Contaminant limit exceeded
|
Aug 1, 1996 | Resolved |
Enforcement actions
California regulators took 7 formal enforcement actions against Rancho San Joaquin MWC between 2012 and 2024. The most recent was a compliance order with a penalty in September 2024.
| Date | By | Action | Violations covered |
|---|---|---|---|
| Sep 4, 2024 | California | Compliance order with a penalty | 2 violations (1 health-based): Arsenic, Public Notice |
| Apr 10, 2023 | California | Compliance order (no penalty) | 1 violation (1 health-based): Arsenic |
| Jan 13, 2022 | California | Compliance order (no penalty) | 2 violations: Total Trihalomethanes (TTHMs), Haloacetic Acids (HAA5) |
| Apr 20, 2018 | California | Compliance order (no penalty) | 1 violation: Lead and Copper Rule |
| Mar 28, 2018 | California | Compliance order (no penalty) | 1 violation: Revised Total Coliform Rule |
| Dec 7, 2012 | California | Compliance order (no penalty) | 3 violations: Total Coliform, Consumer Confidence Rule |
| Sep 14, 2012 | California | Compliance order (no penalty) | 1 violation: Total Coliform |
What the violations mean
Arsenic
2 incidentsArsenic exceeded the federal limit
Long-term arsenic exposure is linked to cancer and cardiovascular effects
LEAD AND COPPER RULE REVISIONS
1 incidentThe system did not complete a treatment step or action that the LEAD AND COPPER RULE REVISIONS requires (a treatment technique violation).
The utility had to notify customers about this violation.
Where the water comes from
Rancho San Joaquin MWC draws water from 1 well.
Annual water quality report
Rancho San Joaquin MWC 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.
Where the state allows it, systems serving fewer than 10,000 people may publish the report in a local newspaper or news site instead of mailing it, and must provide a copy on request.
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 California.
Certified drinking water labs by state EPA guidance for private wells