Public water system record
City of Manteca
Serves Manteca, San Joaquin County, CA · 84,928 people served
Federal records show no health-based violations and 1 monitoring/reporting issue for City of Manteca in the last ten years.
System profile
- Health-based violations, last 10 years
- 0
- Resolved
- 0
- Unresolved
- 0
- Any acute record
- No
- Monitoring issues, last 10 years
- 1
Key facts
- City of Manteca draws water from 18 wells (2 of them for emergency, seasonal or other part-time use).
- Most recent formal enforcement: compliance order (no penalty) by California, March 2025.
- Record on file since 1987, with 36 health-based violations before October 19, 2016.
- Lead pipe inventory: 0 lead and 0 unknown out of 26,435 service lines.
Check whether City of Manteca 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.
None since October 2016.
Monitoring and reporting issues
Since October 2016Missed tests or reports, not contaminants found above a limit.
| Issue | Start date | Status |
|---|---|---|
|
Nitrate
Monitoring and reporting
|
Jan 1, 2024 | Resolved |
Full record since 1987
EPA's records for City of Manteca go back to 1987. Before October 19, 2016 they list 36 health-based violations (32 resolved, 4 archived by EPA without a recorded fix) and 5 monitoring or reporting violations.
| Violations that began in | Health-based | Monitoring and reporting |
|---|---|---|
| 1980s | 4 | 5 |
| 1990s | 3 | 0 |
| 2000s | 14 | 0 |
| 2010 to October 18, 2016 | 15 | 0 |
| 2020s | 0 | 1 |
Most recent health-based violation before October 19, 2016: Arsenic, began July 2013, Resolved.
Show all 36 health-based violations before October 19, 2016
| Contaminant | Start date | Status |
|---|---|---|
|
Arsenic
Contaminant limit exceeded
Measured 0.011 mg/L, federal limit 0.01 mg/L (1.1 times the limit)
|
Jul 1, 2013 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.0115 mg/L, federal limit 0.01 mg/L (1.2 times the limit)
|
Apr 1, 2013 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.0118 mg/L, federal limit 0.01 mg/L (1.2 times the limit)
|
Jan 1, 2013 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.0121 mg/L, federal limit 0.01 mg/L (1.2 times the limit)
|
Oct 1, 2012 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.0128 mg/L, federal limit 0.01 mg/L (1.3 times the limit)
|
Jul 1, 2012 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.0139 mg/L, federal limit 0.01 mg/L (1.4 times the limit)
|
Apr 1, 2012 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.0136 mg/L, federal limit 0.01 mg/L (1.4 times the limit)
|
Jan 1, 2012 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.0178 mg/L, federal limit 0.01 mg/L (1.8 times the limit)
|
Oct 1, 2011 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.0179 mg/L, federal limit 0.01 mg/L (1.8 times the limit)
|
Jul 1, 2011 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.0175 mg/L, federal limit 0.01 mg/L (1.8 times the limit)
|
Apr 1, 2011 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.018 mg/L, federal limit 0.01 mg/L (1.8 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 0.0199 mg/L, federal limit 0.01 mg/L (2 times the limit)
|
Jul 1, 2010 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.021 mg/L, federal limit 0.01 mg/L (2.1 times the limit)
|
Apr 1, 2010 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.013 mg/L, federal limit 0.01 mg/L (1.3 times the limit)
|
Jan 1, 2010 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.0133 mg/L, federal limit 0.01 mg/L (1.3 times the limit)
|
Oct 1, 2009 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.0188 mg/L, federal limit 0.01 mg/L (1.9 times the limit)
|
Jul 1, 2009 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.0206 mg/L, federal limit 0.01 mg/L (2.1 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 0.021 mg/L, federal limit 0.01 mg/L (2.1 times the limit)
|
Oct 1, 2008 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.021 mg/L, federal limit 0.01 mg/L (2.1 times the limit)
|
Jul 1, 2008 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.019 mg/L, federal limit 0.01 mg/L (1.9 times the limit)
|
Apr 1, 2008 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.02 mg/L, federal limit 0.01 mg/L (2 times the limit)
|
Jan 1, 2008 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.019 mg/L, federal limit 0.01 mg/L (1.9 times the limit)
|
Oct 1, 2007 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.018 mg/L, federal limit 0.01 mg/L (1.8 times the limit)
|
Jul 1, 2007 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.18 mg/L, federal limit 0.01 mg/L (18 times the limit)
|
Apr 1, 2007 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.018 mg/L, federal limit 0.01 mg/L (1.8 times the limit)
|
Jan 1, 2007 | Resolved |
|
Arsenic
Contaminant limit exceeded
Measured 0.011 mg/L, federal limit 0.01 mg/L (1.1 times the limit)
|
Oct 1, 2006 | Resolved |
|
Nitrate (acute)
Contaminant limit exceeded
|
Dec 4, 2001 | Resolved |
|
Total Coliform
Contaminant limit exceeded
|
Jun 1, 1993 | Resolved |
|
Total Coliform
Contaminant limit exceeded
|
May 1, 1993 | Resolved |
|
Total Coliform
Contaminant limit exceeded
|
Oct 1, 1992 | Resolved |
|
Selenium
Contaminant limit exceeded
|
Jul 1, 1987 | Archived |
|
Nitrate (acute)
Contaminant limit exceeded
|
Jul 1, 1987 | Archived |
|
Fluoride
Contaminant limit exceeded
|
Jul 1, 1987 | Archived |
|
Arsenic
Contaminant limit exceeded
|
Jul 1, 1987 | Archived |
Enforcement actions
California regulators took 3 formal enforcement actions against City of Manteca between 2002 and 2025. The most recent was a compliance order (no penalty) in March 2025.
| Date | By | Action | Violations covered |
|---|---|---|---|
| Mar 6, 2025 | California | Compliance order (no penalty) | 1 violation: Nitrate |
| Jan 5, 2009 | California | Compliance order (no penalty) | 28 violations (28 health-based): Arsenic |
| Feb 7, 2002 | California | Compliance order (no penalty) | 1 violation (1 health-based): Nitrate |
Where the water comes from
City of Manteca draws water from 18 wells (2 of them for emergency, seasonal or other part-time use). It also buys water from South San Joaquin Irrigation District.
Buys water from
- South San Joaquin Irrigation District Ripon, CA
Annual water quality report
City of Manteca 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 10,000 or more people must mail or deliver the report to every customer, and from 2027 they must send it twice a year.
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