Water Quality in Eureka, MO: 3 Violations — Grade C
Grade C · Score 62/100 · 3 water systems · Updated 2026-05-03
Eureka's water has moderate compliance issues. Residents in affected areas should consider filtration.
Data: EPA Safe Drinking Water Information System (SDWIS) Last verified: 2026-05-03
Tracked under the EPA Safe Drinking Water program, Eureka, MO shows 3 water violations on file — findings that span multiple violation categories and are detailed system by system in the data grid further down the page.
Water Quality by ZIP Code in Eureka
Water quality varies across Eureka's 1 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 63025 | C | 62 | 3 | 0 | View report → |
Water Quality Overview
Eureka, Missouri receives a water quality grade of C with an overall score of 62 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 3 water systems serving Eureka have accumulated 3 EPA violations (all monitoring/reporting type). These violations are tracked across 1 ZIP codes serving approximately 16,618 people.
What Grade C Means
A grade of C indicates moderate compliance issues. Eureka's water systems have some violations that warrant attention. While the water may still be safe for most people, residents in affected ZIP codes should consider additional testing or filtration.
Lead Levels
The average 90th percentile lead level across Eureka water systems is 0.0031 mg/L — within EPA limits. No ZIP codes exceed the EPA lead action level.
Radon Risk
Eureka is in EPA Radon Zone 2 (Moderate risk). Testing is recommended, especially for homes with basements or ground-level living spaces.
Water Systems Serving Eureka
Eureka is served by 3 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 16,618 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 5 enforcement actions against water systems serving Eureka. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Eureka
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 Eureka Water Systems
The following contaminants have been detected or caused violations across Eureka's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| E. coli | Microbiological | N/A | 1 | 1 | No |
| Fecal Coliform | Microbiological | N/A | 1 | 1 | No |
| Stage 1 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 5 enforcement actions against water systems serving Eureka. Recent actions:
| Date | Action Type |
|---|---|
| 2025-05-06 | State Order Extension |
| 2025-04-07 | State Order Extension |
| 2025-03-26 | State Informal Action |
| 2025-02-27 | State Informal Action |
| 2025-02-27 | State Informal Enforcement |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-05-06.
Eureka vs. Nearby Missouri Cities
How Eureka's water quality compares to similar cities in Missouri:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Eureka | C | 3 | 3 | 16,618 |
| Cottleville | B | 0 | 5 | 16,653 |
| Grover | C | 0 | 1 | 16,548 |
| Republic | B | 1 | 2 | 16,415 |
Common Questions About Eureka Water
These are the most common questions residents search for about water quality in Eureka, Missouri:
Is Eureka water hard or soft? Water hardness varies by source. Eureka's 3 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Eureka tap water? Eureka's water receives a grade of C (62/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Eureka? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Eureka vs. Missouri Average
Understanding how Eureka compares to the broader Missouri 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 Eureka.
ZIP Codes in Eureka
Eureka spans 1 ZIP code. The ZIP with the lowest water quality score is 63025. 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.