City of Oakdale
EPA ID: CA5010014 · 23,235 people served · 1 ZIP code
ZipCheckup's reading of EPA records for City of Oakdale (CA5010014): 2 violations recorded with unresolved status in the SDWIS data used. Federal data lists 2 violations as unresolved at City of Oakdale - roughly 23,235 residents in the service area.
Data: EPA SDWIS
Service Area Map
Coverage area for City of Oakdale Source: EPA SDWIS service area boundaries.
Service area boundary - average Home Safety grade of mapped ZIPs: A
Demographics of ZIP Codes Served
The ZIP codes associated with City of Oakdale have a median household income of $91,381 and about 35,024 residents live in those ZIP codes (Census; not the number of people this system supplies). Approximately 50% of housing stock was built before 1986, which increases the likelihood of lead service lines and older plumbing.
Environmental Justice Note: On average, 54% of census tracts in the counties mapped to this service area are designated disadvantaged by the federal Climate and Economic Justice Screening Tool (CEJST, 2022 version). Communities with higher disadvantaged populations often face disproportionate environmental and health burdens, including aging water infrastructure and limited resources for remediation.
💧 Where Does Your Water Come From?
City of Oakdale's water is classified in EPA records as a groundwater source. Groundwater is naturally filtered through rock and soil, but it can be vulnerable to PFAS contamination, nitrates from agriculture, and industrial chemicals that seep into the water table.
Superfund Proximity Note: This service area ranks in the 80th percentile nationally for proximity to Superfund (NPL) sites. Groundwater sources near contaminated sites may face elevated risk from industrial chemicals.
Infrastructure Risk
Comparable Water Systems
Similar-sized systems in California
Estimated Remediation Costs
Average estimated costs across ZIP codes served by this system
Based on national averages for common remediation projects. Actual costs vary by property. Only issues flagged by EPA, FEMA, or state data for each ZIP code are included.
System Overview
City of Oakdale, (EPA ID: CA5010014) is a community water system in California that serves approximately 23,235 people from groundwater sources.
This system serves ZIP code 95361 in Oakdale.
ZIP-Area Home Safety Context: A (87/100)
This is the average Home Safety Score for 1 of 1 service-area ZIP codes with all required score domains observed. It is not a grade for the water utility.
Model 4.0.0 uses SDWIS identity plus accepted ECHO SDWA lifecycle-based water compliance, the UCMR 5 PFAS MCL screen, EPA radon zone, and annual EPA AirData AQI across three equally weighted domains. Missing required evidence suppresses the score.
Violation History
Status breakdown for accepted records with record years 2021-2026: 0 resolved, 0 archived, 2 addressed, and 0 unaddressed. Under this source contract, current noncompliance is the sum of addressed and unaddressed records. Archived and resolved records are excluded from current noncompliance.
Recent Violations
| Date | Contaminant | Type | Status |
|---|---|---|---|
| October 17, 2024 | LEAD AND COPPER RULE REVISIONS | Health-based | Addressed (current) |
| October 17, 2024 | LEAD AND COPPER RULE REVISIONS | Non-health-based | Addressed (current) |
Contaminants Detected
The following contaminants have been flagged in EPA records for this water system:
| Contaminant | Category | Violations | Health-Based |
|---|---|---|---|
| LEAD AND COPPER RULE REVISIONS | Treatment Technique, Monitoring & Reporting | 2 | Yes |
Lead & Copper
EPA Lead and Copper Rule evidence attributed directly to this water system:
| Lead Level | Exceeds Action Level | Sample Date |
|---|---|---|
| Below the reporting limit | No | 2025-12-31 |
No copper action-level exceedance record appears for this PWSID in the accepted LCR snapshot. This does not establish a clean copper measurement.
Radon Risk in Service Area
1 of 1 ZIP records with known zones is in EPA Radon Zone 3.
The EPA recommends testing all homes regardless of radon zone. County radon zones cannot replace an in-home radon test.
ZIP Codes Served
Coverage: Service area ZIP codes sourced from EPA Community Water System Service Area Boundaries v3 (March 2026 release). These ZIPs reflect the actual deployment footprint recorded by CA or modeled from parcel and building-footprint data.
- 95361 - Oakdale
Data Sources
This report uses public data from the EPA Safe Drinking Water Information System (SDWIS). View available EPA compliance records for City of Oakdale (CA5010014) on EPA.gov.
Frequently Asked Questions
Is City of Oakdale water safe to drink?
The accepted 2026Q2 ECHO snapshot shows 1 current health-based noncompliance record for City of Oakdale. Review the utility's current notices and EPA record. This system-level compliance history cannot determine conditions at a specific tap.
How many people does City of Oakdale serve?
City of Oakdale serves approximately 23,235 people across 1 ZIP code in California.
Where does City of Oakdale get its water?
The primary water source is groundwater.
Federal UCMR5 PFAS Monitoring: No PFAS Reported Above Reporting Levels
This water system was tested under the federal EPA Unregulated Contaminant Monitoring Rule (UCMR5). No PFAS compounds were reported above UCMR5 minimum reporting levels.
EPA's April 2024 PFAS rule sets MCLs of 4 ppt for PFOA and PFOS and 10 ppt for PFHxS, PFNA and HFPO-DA (GenX); water systems must comply from 2029. Other PFAS compounds have no individual federal MCL. A state standard is shown only where this system's state has its own enforceable PFAS limit. Detection results are EPA UCMR5 samples, not a measurement at your tap.
Source: U.S. EPA UCMR5 (Unregulated Contaminant Monitoring Rule, 5th cycle) — per-system federal sampling, 2023–2025. EPA UCMR5 monitoring program →
How Water Systems Appear in Rankings
Water systems are evaluated by violation history, contaminant detections, and service population. Larger systems with more service connections appear in more rankings.
Frequently Asked Questions
How to cite this page
ZipCheckup. (n.d.). City of Oakdale (CA): 1 Health Violation. https://zipcheckup.com/water-system/ca5010014/
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author = {{ZipCheckup}},
title = {{City of Oakdale (CA): 1 Health Violation}},
year = {n.d.},
url = {https://zipcheckup.com/water-system/ca5010014/}
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What You Can Do
Test your water
Home test kits can detect lead, bacteria, and other contaminants at your tap. Find the right filter →
Check your specific ZIP code
Water quality can vary within a system. View nearest ZIP report →
Contact your utility
City of Oakdale (EPA ID: CA5010014) - request the latest Consumer Confidence Report or ask about specific contaminants.