Water Quality in Cincinnati, OH: 23 Violations - Grade N/A
13 water systems · 46 directly mapped ZIP records
Available EPA records report 23 violations across 46 directly mapped ZIP records with known counts for Cincinnati. This is compliance evidence, not a property-level tap-water verdict.
Data: EPA Safe Drinking Water Information System (SDWIS)
Water Quality by ZIP Code in Cincinnati
This table shows typed EPA water evidence only. Missing violation counts are displayed as N/A, not zero.
| ZIP Code | Violations | Health | |
|---|---|---|---|
| 45215 | 7 | 0 | View report → |
| 45236 | 6 | 0 | View report → |
| 45237 | 6 | 0 | View report → |
| 45241 | 5 | 0 | View report → |
| 45246 | 5 | 0 | View report → |
| 45249 | 5 | 0 | View report → |
| 45245 | 3 | 0 | View report → |
| 45248 | 3 | 0 | View report → |
| 45255 | 3 | 0 | View report → |
| 45244 | 2 | 0 | View report → |
| 45231 | 1 | 0 | View report → |
| 45242 | 1 | 0 | View report → |
| 45202 | 0 | 0 | View report → |
| 45203 | 0 | 0 | View report → |
| 45204 | 0 | 0 | View report → |
Water Quality Overview
Cincinnati, Ohio has directly mapped EPA water-system data for 46 ZIP codes. This page reports typed compliance facts and does not relabel the multi-source Home Safety Score as a drinking-water grade.
The available EPA records report 23 violations (all classified as monitoring/reporting type in the available record) across 46 directly mapped ZIP records with reported counts.
Lead Levels
The average 90th percentile lead level across Cincinnati water systems is 0.0022 mg/L - within EPA limits. No exceedances appear among the 46 ZIP records with known lead status.
With 79% of homes built before 1986, Cincinnati 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 Cincinnati
Cincinnati is served by 13 community water systems regulated under the Safe Drinking Water Act. These systems collectively serve approximately 814,555 people across 71 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 86 enforcement actions against water systems serving Cincinnati. Enforcement actions range from informal compliance assistance to formal orders and penalties.
How to Check Your Water in Cincinnati
Enter your ZIP code on ZipCheckup to see your specific water system data, including contaminant levels and violation history
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 Cincinnati Water Systems
The following contaminants have been detected or caused violations across Cincinnati's water systems:
| Contaminant | Category | MCL | Violations | ZIPs Affected | Health-Based |
|---|---|---|---|---|---|
| Surface Water Treatment Rule | Treatment Technique | N/A | 32 | 11 | No |
| Total Trihalomethanes (TTHM) | Disinfection Byproducts | 0.08 mg/L | 7 | 5 | No |
| Stage 2 DBP Rule | Treatment Technique | N/A | 4 | 4 | No |
| Lead and Copper Rule | Treatment Technique | N/A | 3 | 2 | No |
| Lead | Inorganic | 0.015 mg/L | 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 34 enforcement actions against water systems serving Cincinnati. Recent actions:
| Date | Action Type |
|---|---|
| 2025-12-12 | State Informal Action |
| 2025-12-09 | State Order Extension |
| 2025-11-19 | State Informal Action |
| 2025-10-21 | State Informal Action |
| 2025-10-21 | State Informal Enforcement |
| 2025-08-18 | State Informal Action |
| 2025-06-24 | State Order Extension |
| 2025-05-14 | State Order Extension |
| 2024-12-31 | State Order Extension |
| 2024-12-31 | State Informal Action |
Enforcement actions range from informal compliance assistance to formal orders and penalties. The most recent action was on 2025-12-12.
Cincinnati vs. Nearby Ohio Cities
How Cincinnati's water quality compares to similar cities in Ohio:
| City | Direct EPA ZIPs | Violations | Systems | Population |
|---|---|---|---|---|
| Cincinnati | 46 | 23 | 13 | 814,555 |
| Columbus | 31 | 29 | 17 | 874,256 |
| Cleveland | 28 | 8 | 2 | 734,002 |
| Dayton | 29 | 19 | 19 | 485,366 |
Water Quality by ZIP Code in Cincinnati
EPA coverage and recorded violations can differ across Cincinnati's ZIP codes. Missing counts are shown as unavailable, not zero:
| ZIP Code | Violations | Health-Based |
|---|---|---|
| 45215 | 7 | 0 |
| 45236 | 6 | 0 |
| 45237 | 6 | 0 |
| 45241 | 5 | 0 |
| 45246 | 5 | 0 |
| 45249 | 5 | 0 |
| 45245 | 3 | 0 |
| 45248 | 3 | 0 |
| 45255 | 3 | 0 |
| 45244 | 2 | 0 |
| 45231 | 1 | 0 |
| 45242 | 1 | 0 |
| 45202 | 0 | 0 |
| 45203 | 0 | 0 |
| 45204 | 0 | 0 |
Common Questions About Cincinnati Water
These are the most common questions residents search for about water quality in Cincinnati, Ohio:
Is Cincinnati water hard or soft? Water hardness varies by source. Cincinnati's 13 water systems use multiple sources. Check your ZIP code report for specific hardness data.
Can I drink Cincinnati tap water? City-level EPA records cannot determine safety at a specific tap. No health-based violations are recorded across 46 directly mapped ZIP records with known counts, but this is not a property-level safety guarantee.
What is the best water filter for Cincinnati? A NSF/ANSI 53-certified filter for lead removal is a good general choice. See our Water Filter Matcher for personalized recommendations.
Cincinnati vs. Ohio Average
Understanding how Cincinnati compares to the broader Ohio 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 Cincinnati.
ZIP Codes in Cincinnati
Cincinnati spans 71 ZIP codes. EPA water-system coverage is available for 46 directly mapped ZIP codes. 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
Source reporting periods vary. See each cited source for its publication schedule.