Public water system record

Bass Lake Heights Mutual Water

Serves an area of Madera County, CA · 250 people served

Federal records show 2 health-based violations and 8 monitoring/reporting issues for Bass Lake Heights Mutual Water in the last ten years, including an unresolved LEAD AND COPPER RULE REVISIONS violation.

CA2000502
OAKHURST
CA
250 served

System profile

Source water Groundwater

ZIP 93644

EPA system ID CA2000502

Verify this system on EPA ECHO →

Health-based violations, last 10 years: 2
Resolved: 1
Unresolved: 1
Any acute record: No
Monitoring issues, last 10 years: 8

Key facts

Bass Lake Heights Mutual Water draws water from 3 wells (1 of them for emergency, seasonal or other part-time use).
Highest measured level in the last 10 years: Arsenic, 0.012 mg/L, federal limit 0.01 mg/L (1.2 times the limit), 2017.
Most recent formal enforcement: compliance order (no penalty) by California, August 2014.
Record on file since 1980, with 31 health-based violations before October 19, 2016.

Check whether Bass Lake Heights Mutual Water serves your address

Health-based violations

Since October 2016

Violation 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 0.012 mg/L, federal limit 0.01 mg/L (1.2 times the limit)	330	Sep 1, 2017	Resolved	No

Monitoring and reporting issues

Since October 2016

Missed tests or reports, not contaminants found above a limit.

Issue	Start date	Status
LEAD AND COPPER RULE REVISIONS RPT	Oct 17, 2024	Active
Nitrate Monitoring and reporting	Jan 1, 2023	Resolved
Asbestos Monitoring and reporting	Jan 1, 2017	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
Asbestos Monitoring and reporting	Jan 1, 2017	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
Asbestos Monitoring and reporting	Jan 1, 2017	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
Asbestos Monitoring and reporting	Jan 1, 2016	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
Asbestos Monitoring and reporting	Jan 1, 2016	Archived Violation period ended. EPA no longer counts it toward current compliance, but no fix was formally recorded.
Consumer Confidence Rule OTHER	Jul 1, 2011	Resolved

Full record since 1980

EPA's records for Bass Lake Heights Mutual Water go back to 1980. Before October 19, 2016 they list 31 health-based violations (31 resolved) and 9 monitoring or reporting violations.

Violations that began in	Health-based	Monitoring and reporting
1980s	0	2
1990s	0	1
2000s	15	3
2010 to October 18, 2016	16	3
October 19, 2016 to 2019	1	3
2020s	1	2

Most recent health-based violation before October 19, 2016: Total Coliform, began November 2014, Resolved.

Show all 31 health-based violations before October 19, 2016

Contaminant	Start date	Status
Total Coliform Contaminant limit exceeded	Nov 1, 2014	Resolved
Arsenic Contaminant limit exceeded Measured 0.019 mg/L, federal limit 0.01 mg/L (1.9 times the limit)	Jan 1, 2011	Resolved
Arsenic Contaminant limit exceeded Measured 0.02 mg/L, federal limit 0.01 mg/L (2 times the limit)	Jan 1, 2011	Resolved
Arsenic Contaminant limit exceeded Measured 0.023 mg/L, federal limit 0.01 mg/L (2.3 times the limit)	Jan 1, 2011	Resolved
Arsenic Contaminant limit exceeded Measured 0.019 mg/L, federal limit 0.01 mg/L (1.9 times the limit)	Oct 1, 2010	Resolved
Arsenic Contaminant limit exceeded Measured 0.02 mg/L, federal limit 0.01 mg/L (2 times the limit)	Oct 1, 2010	Resolved
Arsenic Contaminant limit exceeded Measured 0.023 mg/L, federal limit 0.01 mg/L (2.3 times the limit)	Oct 1, 2010	Resolved
Arsenic Contaminant limit exceeded Measured 0.019 mg/L, federal limit 0.01 mg/L (1.9 times the limit)	Jul 1, 2010	Resolved
Arsenic Contaminant limit exceeded Measured 0.02 mg/L, federal limit 0.01 mg/L (2 times the limit)	Jul 1, 2010	Resolved
Arsenic Contaminant limit exceeded Measured 0.023 mg/L, federal limit 0.01 mg/L (2.3 times the limit)	Jul 1, 2010	Resolved
Arsenic Contaminant limit exceeded Measured 0.019 mg/L, federal limit 0.01 mg/L (1.9 times the limit)	Apr 1, 2010	Resolved
Arsenic Contaminant limit exceeded Measured 0.02 mg/L, federal limit 0.01 mg/L (2 times the limit)	Apr 1, 2010	Resolved
Arsenic Contaminant limit exceeded Measured 0.023 mg/L, federal limit 0.01 mg/L (2.3 times the limit)	Apr 1, 2010	Resolved
Arsenic Contaminant limit exceeded Measured 0.02 mg/L, federal limit 0.01 mg/L (2 times the limit)	Jan 1, 2010	Resolved
Arsenic Contaminant limit exceeded Measured 0.02 mg/L, federal limit 0.01 mg/L (2 times the limit)	Jan 1, 2010	Resolved
Arsenic Contaminant limit exceeded Measured 0.012 mg/L, federal limit 0.01 mg/L (1.2 times the limit)	Jan 1, 2010	Resolved
Arsenic Contaminant limit exceeded Measured 0.02 mg/L, federal limit 0.01 mg/L (2 times the limit)	Oct 1, 2009	Resolved
Arsenic Contaminant limit exceeded Measured 0.012 mg/L, federal limit 0.01 mg/L (1.2 times the limit)	Oct 1, 2009	Resolved
Arsenic Contaminant limit exceeded Measured 0.0198 mg/L, federal limit 0.01 mg/L (2 times the limit)	Oct 1, 2009	Resolved
Arsenic Contaminant limit exceeded Measured 0.012 mg/L, federal limit 0.01 mg/L (1.2 times the limit)	Jul 1, 2009	Resolved
Arsenic Contaminant limit exceeded Measured 0.02 mg/L, federal limit 0.01 mg/L (2 times the limit)	Jul 1, 2009	Resolved
Arsenic Contaminant limit exceeded Measured 0.0198 mg/L, federal limit 0.01 mg/L (2 times the limit)	Jul 1, 2009	Resolved
Arsenic Contaminant limit exceeded Measured 0.0203 mg/L, federal limit 0.01 mg/L (2 times the limit)	Apr 1, 2009	Resolved
Arsenic Contaminant limit exceeded Measured 0.0207 mg/L, federal limit 0.01 mg/L (2.1 times the limit)	Apr 1, 2009	Resolved
Arsenic Contaminant limit exceeded Measured 0.012 mg/L, federal limit 0.01 mg/L (1.2 times the limit)	Apr 1, 2009	Resolved
Arsenic Contaminant limit exceeded Measured 0.0203 mg/L, federal limit 0.01 mg/L (2 times the limit)	Jan 1, 2009	Resolved
Arsenic Contaminant limit exceeded Measured 0.0207 mg/L, federal limit 0.01 mg/L (2.1 times the limit)	Jan 1, 2009	Resolved
Arsenic Contaminant limit exceeded Measured 0.012 mg/L, federal limit 0.01 mg/L (1.2 times the limit)	Jan 1, 2009	Resolved
Arsenic Contaminant limit exceeded Measured 0.0203 mg/L, federal limit 0.01 mg/L (2 times the limit)	Apr 1, 2008	Resolved
Arsenic Contaminant limit exceeded Measured 0.0207 mg/L, federal limit 0.01 mg/L (2.1 times the limit)	Apr 1, 2008	Resolved
Arsenic Contaminant limit exceeded Measured 0.012 mg/L, federal limit 0.01 mg/L (1.2 times the limit)	Oct 1, 2007	Resolved

Enforcement actions

California regulators took 1 formal enforcement action against Bass Lake Heights Mutual Water in 2014. The most recent was a compliance order (no penalty) in August 2014.

Date	By	Action	Violations covered
Aug 12, 2014	California	Compliance order (no penalty)	30 violations (30 health-based): Arsenic

What the violations mean

LEAD AND COPPER RULE REVISIONS

1 incident

The 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.

Arsenic

1 incident

Arsenic exceeded the federal limit

Long-term arsenic exposure is linked to cancer and cardiovascular effects

Where the water comes from

Bass Lake Heights Mutual Water draws water from 3 wells (1 of them for emergency, seasonal or other part-time use).

Annual water quality report

Bass Lake Heights Mutual Water 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.

Systems serving 500 or fewer people may meet the rule by telling customers the report is available on request, so you may need to ask Bass Lake Heights Mutual Water for a copy.

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