Water Quality in Flat Rock, IL: 4 Violations — Grade C
Grade C · Score 66/100 · 1 water system · Updated 2026-05-03
Flat Rock'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
EPA monitoring has flagged 4 reportable events for water systems in Flat Rock, IL.
Water Quality by ZIP Code in Flat Rock
Water quality varies across Flat Rock's 1 ZIP codes. Check your specific ZIP for detailed contaminant data.
| ZIP Code | Grade | Score | Violations | Health | |
|---|---|---|---|---|---|
| 62427 | C | 66 | 4 | 0 | View report → |
Water Quality Overview
Flat Rock, Illinois receives a water quality grade of C with an overall score of 66 out of 100, based on EPA compliance data from the Safe Drinking Water Information System (SDWIS).
The 1 water system serving Flat Rock have accumulated 4 EPA violations (all monitoring/reporting type). These violations are tracked across 1 ZIP codes serving approximately 325 people.
What Grade C Means
A grade of C indicates moderate compliance issues. Flat Rock'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
Lead testing data for Flat Rock is currently being collected. The EPA requires all community water systems to test for lead under the Lead and Copper Rule.
With 63% of homes built before 1986, Flat Rock 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.
Radon Risk
Flat Rock is in EPA Radon Zone 2 (Moderate risk). Testing is recommended, especially for homes with basements or ground-level living spaces.
Water Systems Serving Flat Rock
Flat Rock is served by 1 community water system regulated under the Safe Drinking Water Act. These systems collectively serve approximately 325 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 7 enforcement actions against water systems serving Flat Rock. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Flat Rock
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 Flat Rock Water Systems
The following contaminants have been detected or caused violations across Flat Rock's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Surface Water Treatment Rule | Treatment Technique | N/A | 3 | 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 7 enforcement actions against water systems serving Flat Rock. Recent actions:
| Date | Action Type |
|---|---|
| 2025-09-16 | State Informal Action |
| 2025-09-06 | State Informal Action |
| 2025-07-03 | State Informal Action |
| 2025-07-03 | State Informal Enforcement |
| 2024-08-28 | State Informal Action |
| 2024-08-08 | State Order Extension |
| 2024-07-31 | State Informal Action |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-09-16.
Flat Rock vs. Nearby Illinois Cities
How Flat Rock's water quality compares to similar cities in Illinois:
| City | Grade | Violations | Systems | Population |
|---|---|---|---|---|
| Flat Rock | C | 4 | 1 | 325 |
| Kinderhook | B | 0 | 1 | 322 |
| Seatonville | C | 0 | 1 | 321 |
| Bingham | D | 0 | 1 | 330 |
Common Questions About Flat Rock Water
These are the most common questions residents search for about water quality in Flat Rock, Illinois:
Is Flat Rock water hard or soft? Water hardness varies by source. Flat Rock's 1 water system uses a single source. Check your ZIP code report for specific hardness data.
Can I drink Flat Rock tap water? Flat Rock's water receives a grade of C (66/100). No health-based violations have been recorded, but home testing is always recommended.
What is the best water filter for Flat Rock? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Flat Rock vs. Illinois Average
Understanding how Flat Rock compares to the broader Illinois 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 Flat Rock.
ZIP Codes in Flat Rock
Flat Rock spans 1 ZIP code. The ZIP with the lowest water quality score is 62427. 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.