B66/100
Cincinnati Tap Water Quality: Is It Safe to Drink? (2026 Report)
Serving 776,318 residents · Ohio
What's In Cincinnati's Tap Water?
77
Contaminants Tested
1
Exceed EPA Limits
2
Above EPA Goals
3 contaminants above EPA health goals
| Contaminant | Detected | Limit (MCL) | Status |
|---|---|---|---|
Copper (90th percentile) | 37.60 mg/L | 1.30 mg/L | Over Limit |
1,4-dioxane | 0.580 µg/L | — | Above Goal |
Lead (90th percentile) | 0.002 mg/L | 0.015 mg/L | Above Goal |
EPA Violation History
No violations in the past 5 years
This system has a clean compliance history.
Understanding violation severity
Tier 1Urgent health risk. Utility must notify all customers within 24 hours.Tier 2Important health or treatment issue. Customers notified within 30 days.Tier 3Administrative or monitoring issue. Reported in the annual water quality report.
Source: EPA Safe Drinking Water Information System (SDWIS) · Updated quarterly
Water Utility Details
TIMBERBROOK MOBILE HOME PARK
Population Served
1,418
Water Source
Groundwater
System ID
IN5220027
INDIAN HILL CITY PWS
Population Served
15,000
Water Source
Groundwater
System ID
OH3101112
WYOMING CITY PWS
Population Served
9,700
Water Source
Groundwater
System ID
OH3102212
CINCINNATI PUBLIC WATER SYSTEM
Population Served
750,200
Water Source
Surface Water
System ID
OH3102612
Frequently Asked Questions About Cincinnati Water
Is Cincinnati tap water safe to drink?
Cincinnati, Ohio tap water receives a grade of B (66/100), which is considered good. Out of 77 contaminants tested, 2 exceed EPA maximum contaminant levels (MCLs) and 4 exceed health guidelines (MCLGs). While the water meets federal standards, some residents may still choose to use a filter for additional peace of mind.
What contaminants are in Cincinnati's water?
Of the 77 contaminants tested in Cincinnati's water supply, the most notable include Copper (90th percentile), PFOS, Lead (90th percentile), 1,4-dioxane. 2 contaminant(s) exceed EPA legal limits (MCLs). 4 contaminant(s) exceed EPA health goals (MCLGs), which are non-enforceable targets set at levels with no known health risk.
Does Cincinnati have any water quality violations?
Yes, Cincinnati has 58 EPA violation(s) on record, with the most recent in 2023. Violation types include Other, MCL, MR. 9 of these are health-based violations, which are the most serious category.
Do I need a water filter in Cincinnati?
Based on EPA data, using a water filter in Cincinnati is recommended. 2 contaminant(s) exceed legal limits. An NSF-certified filter — such as a reverse osmosis or activated carbon system — can effectively reduce many common contaminants. Choose a filter certified to remove the specific contaminants found in your area.
Where does Cincinnati's tap water come from?
Cincinnati's drinking water is sourced from groundwater and supplied by TIMBERBROOK MOBILE HOME PARK and 3 other water system(s). The system serves approximately 776,318 people. Groundwater is pumped from underground aquifers, which often provides natural filtration.
How often is Cincinnati's water tested?
Under the Safe Drinking Water Act (SDWA), water utilities are required to regularly test for over 90 contaminants. Testing frequency varies by contaminant — some are tested monthly, others quarterly or annually. Cincinnati's water systems must report results to the EPA and publish an annual Consumer Confidence Report (CCR). The data on this page reflects the latest available EPA testing data.
How does Cincinnati's water compare to other cities in Ohio?
Cincinnati's water quality score of 66/100 earns a grade of B, which is considered good. This is an above-average score compared to many cities nationwide. Visit our Ohio state page to see how all cities in the state compare.
What should I do if I'm concerned about Cincinnati's water quality?
If you have concerns about Cincinnati's tap water, consider these steps: (1) Request your utility's annual Consumer Confidence Report for detailed local data. (2) Get your water independently tested through a state-certified laboratory. (3) Consider an NSF-certified water filter rated for the contaminants found in your area. (4) Contact your water utility (TIMBERBROOK MOBILE HOME PARK) with specific questions. (5) Report water quality issues to your state drinking water program or the EPA Safe Drinking Water Hotline at 800-426-4791.