Water Quality in Mckinleyville, CA: 2 Violations — Grade A
Grade A · Score 88/100 · 2 water systems · Updated 2026-05-03
Mckinleyville's water meets all EPA standards with no health-based violations.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
Mckinleyville in CA has 2 EPA water violations documented — the compliance history below covers what was flagged and which local systems are associated with each finding.
Water Quality by ZIP Code in Mckinleyville
Water quality varies across Mckinleyville's 1 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 95519 | A | 88 | 2 | 0 | View report → |
Water Quality Overview
Mckinleyville, California receives a water quality grade of A with an overall score of 88 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 2 water systems serving Mckinleyville have accumulated 2 EPA violations (all monitoring/reporting type). These violations are tracked across 1 ZIP codes serving approximately 18,745 people.
What Grade A Means
A grade of A indicates excellent compliance with EPA drinking water standards. Mckinleyville's water systems have maintained strong performance in both contaminant monitoring and regulatory compliance.
Lead Levels
The average 90th percentile lead level across Mckinleyville water systems is 0.0018 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
With 43% of homes built before 1986, Mckinleyville has a higher-than-average risk of lead from older plumbing. Lead solder was banned in 1986, and homes built before this date may have lead in pipes, solder joints, or fixtures.
Water Systems Serving Mckinleyville
Mckinleyville is served by 2 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 18,745 people across 1 ZIP codes.
Each water system is identified by a Public Water System ID (PWSID) and is required to:
- Test for over 90 regulated contaminants on a regular schedule
- Report results to the EPA and state regulators
- Issue an annual Consumer Confidence Report (CCR) to all customers
- Take corrective action when violations occur
The EPA has taken 2 enforcement actions against water systems serving Mckinleyville. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Mckinleyville
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels, violation history, and safety scores
Request your CCR — your water utility must provide an annual Consumer Confidence Report with detailed test results for all monitored contaminants
Get a home test — certified kits cost $20–$50 and test for lead, bacteria, and common contaminants. Professional lab tests ($150–$400) cover a broader panel
Consider filtration — NSF-certified filters can remove specific contaminants. Reverse osmosis removes the broadest range; activated carbon is effective for chlorine and many organics
Check for advisories — monitor your local utility website and local news for boil water advisories or system alerts
Contaminants Detected in Mckinleyville Water Systems
The following contaminants have been detected or caused violations across Mckinleyville's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Stage 1 DBP Rule | Treatment Technique | N/A | 1 | 1 | No |
| Stage 2 DBP Rule | Treatment Technique | N/A | 1 | 1 | No |
MCL = Maximum Contaminant Level (EPA enforceable standard). Health-based violations indicate levels that may pose direct health risks.
EPA Enforcement History
The EPA and state regulators have taken 2 enforcement actions against water systems serving Mckinleyville. Recent actions:
| Date | Action Type |
|---|---|
| 2023-07-13 | State Filed Suit |
| 2023-06-20 | State Order Extension |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2023-07-13.
Mckinleyville vs. Nearby California Cities
How Mckinleyville's water quality compares to similar cities in California:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Mckinleyville | A | 2 | 2 | 18,745 |
| Twentynine Palms | C | 0 | 1 | 18,795 |
| El Granada | C | 0 | 1 | 18,940 |
| Half Moon Bay | B | 0 | 1 | 18,940 |
Common Questions About Mckinleyville Water
These are the most common questions residents search for about water quality in Mckinleyville, California:
Is Mckinleyville water hard or soft? Water hardness varies by source. Mckinleyville's 2 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Mckinleyville tap water? Mckinleyville's water receives a grade of A (88/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Mckinleyville? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Mckinleyville vs. California Average
Understanding how Mckinleyville compares to the broader California average helps contextualize your local water quality. Factors like water source, treatment methods, and infrastructure age all contribute to differences between cities in the same state.
To see how individual neighborhoods compare, check the ZIP code reports below — water quality can vary significantly even within Mckinleyville.
ZIP Codes in Mckinleyville
Mckinleyville spans 1 ZIP code. The ZIP with the lowest water quality score is 95519. Each ZIP code has its own water quality profile based on the specific water system serving that area. Check each ZIP code for detailed contaminant data, violation history, and system information.
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Lead/copper: EPA Lead and Copper Rule sampling data
- Radon: EPA Map of Radon Zones
- Enforcement: EPA ECHO database
- Filter recommendations: NSF/ANSI certified products
Updated daily.
Frequently Asked Questions
Your Water is Safe — Here's How to Keep It That Way
Grade A is excellent news. Here's what proactive homeowners do to maintain water quality:
Annual Water Testing
EPA recommends annual testing even with clean water. Home test kits: $20-$50. Catches changes before they become problems.
Maintenance Filtration
A basic carbon filter removes chlorine taste and catches emerging contaminants like PFAS that aren't yet fully regulated.
Plumbing Check
Even safe city water picks up lead from home pipes. If your home was built before 1986, a one-time pipe inspection is recommended.