Public water system record
Oildale MWC
Serves Oildale and Shafter, Kern County, CA · 44,899 people served
Federal records show 5 health-based violations and 2 monitoring/reporting issues for Oildale MWC in the last ten years. The most serious issue in this window was a resolved Total Trihalomethanes (TTHMs) violation.
System profile
- Health-based violations, last 10 years
- 5
- Resolved
- 5
- Unresolved
- 0
- Any acute record
- No
- Monitoring issues, last 10 years
- 2
Key facts
- Oildale MWC draws water from 8 wells (4 of them for emergency, seasonal or other part-time use).
- Highest measured level in the last 10 years: Haloacetic Acids (HAA5), 0.0737 mg/L, federal limit 0.06 mg/L (1.2 times the limit), 2024.
- Most recent formal enforcement: compliance order (no penalty) by California, March 2025.
- Record on file since 1996, with 3 health-based violations before October 19, 2016.
- Lead pipe inventory: 0 lead and 0 unknown out of 12,685 service lines.
Check whether Oildale 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 |
|---|---|---|---|---|
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.0823 mg/L, federal limit 0.08 mg/L (at or just above the limit)
|
220 | Apr 1, 2024 | Resolved | No |
|
Total Trihalomethanes (TTHMs)
Contaminant limit exceeded
Measured 0.0975 mg/L, federal limit 0.08 mg/L (1.2 times the limit)
|
220 | Jan 1, 2024 | Resolved | No |
|
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.0737 mg/L, federal limit 0.06 mg/L (1.2 times the limit)
|
220 | Jan 1, 2024 | Resolved | No |
|
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.0692 mg/L, federal limit 0.06 mg/L (1.2 times the limit)
|
220 | Oct 1, 2023 | Resolved | No |
|
Haloacetic Acids (HAA5)
Contaminant limit exceeded
Measured 0.0609 mg/L, federal limit 0.06 mg/L (at or just above the limit)
|
220 | Jul 1, 2023 | Resolved | 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
Monitoring and reporting
|
Oct 1, 2024 |
Active
Enforcement action in place
|
|
Nitrate-Nitrite
Monitoring and reporting
|
Jan 1, 2016 | Resolved |
Full record since 1996
EPA's records for Oildale MWC go back to 1996. Before October 19, 2016 they list 3 health-based violations (3 resolved) and 3 monitoring or reporting violations.
| Violations that began in | Health-based | Monitoring and reporting |
|---|---|---|
| 1990s | 2 | 0 |
| 2000s | 0 | 2 |
| 2010 to October 18, 2016 | 1 | 1 |
| 2020s | 5 | 1 |
Most recent health-based violation before October 19, 2016: Total Coliform, began October 2015, Resolved.
Show all 3 health-based violations before October 19, 2016
| Contaminant | Start date | Status |
|---|---|---|
|
Total Coliform
Contaminant limit exceeded
|
Oct 1, 2015 | Resolved |
|
Total Coliform
Contaminant limit exceeded
|
Aug 1, 1999 | Resolved |
|
Total Coliform
Contaminant limit exceeded
|
Aug 1, 1996 | Resolved |
Enforcement actions
California regulators took 5 formal enforcement actions against Oildale MWC between 1999 and 2025. The most recent was a compliance order (no penalty) in March 2025.
| Date | By | Action | Violations covered |
|---|---|---|---|
| Mar 19, 2025 | California | Compliance order (no penalty) | 1 violation: Lead and Copper Rule |
| Sep 3, 2024 | California | Compliance order (no penalty) | 5 violations (5 health-based): Haloacetic Acids (HAA5), Total Trihalomethanes (TTHMs) |
| Mar 24, 2017 | California | Compliance order (no penalty) | 1 violation: Nitrate-Nitrite |
| Feb 10, 2016 | California | Compliance order (no penalty) | 1 violation (1 health-based): Total Coliform |
| Sep 29, 1999 | California | Compliance order (no penalty) | 1 violation (1 health-based): Total Coliform |
What the violations mean
Haloacetic Acids (HAA5)
3 incidentsHaloacetic acid byproducts exceeded the federal limit
Long-term exposure to HAAs may increase cancer risk
Total Trihalomethanes (TTHMs)
2 incidentsDisinfection byproduct levels exceeded the federal limit
Long-term TTHM exposure may increase bladder cancer risk
Where the water comes from
Oildale MWC draws water from 8 wells (4 of them for emergency, seasonal or other part-time use). It also buys water from North of the River MWD. 1 smaller public system such as schools, businesses or campgrounds buys water from Oildale MWC. 1 other public water system has an emergency connection to Oildale MWC.
Buys water from
- North of the River MWD Oildale, CA
Annual water quality report
Oildale 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.
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