Water Quality Report · Updated May 12, 2026
CINCINNATI PUBLIC WATER SYSTEM
CINCINNATI PUBLIC WATER SYSTEM delivers tap water graded D (61/100) by TapWaterSafety.org. The utility serves approximately 750,200 residents in CINCINNATI, Ohio using surface water. The most significant water quality concerns are: PFAS contamination; Total trihalomethanes (TTHMs) significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline; Bromodichloromethane significantly above health guideline; Arsenic detected. For questions, the utility can be reached at 513-591-7968.
Is CINCINNATI tap water safe to drink?
CINCINNATI PUBLIC WATER SYSTEM delivers tap water that earns a grade of D (61/100) from TapWaterSafety.org — a below-average rating, with multiple concerns including pfas contamination.
The utility serves 750,200 residents in CINCINNATI, drawing from surface water.
Public testing data identifies 16 contaminants in this water above EWG's health-based guidelines, including: Total trihalomethanes (TTHMs), Haloacetic acids (HAA9), Bromodichloromethane, Dibromochloromethane, Dibromoacetic acid, Haloacetic acids (HAA5), Arsenic, Chloroform, Dichloroacetic acid, Bromoform, Trichloroacetic acid, Chromium (hexavalent), Nitrate and nitrite, Nitrate, Perfluorooctane sulfonate (PFOS), 1,4-Dioxane. For most residents, a properly certified home filter at the kitchen tap is the most cost-effective way to reduce exposure to whatever's in your water. See our filter recommendations below, matched specifically to this utility's contaminant profile.
Quick actions for CINCINNATI residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for CINCINNATI PUBLIC WATER SYSTEM.
PFAS contamination
Severe concernPerfluorooctane sulfonate (PFOS) detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 38.1 ppb, 254x above the EWG health guideline of 0.15 ppb.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 11.6 ppb, 193x above the EWG health guideline of 0.06 ppb.
Bromodichloromethane significantly above health guideline
Moderate concernBromodichloromethane detected at 10.5 ppb, 175x above the EWG health guideline of 0.06 ppb.
Arsenic detected
Moderate concernArsenic detected at 0.233 ppb.
Contact CINCINNATI PUBLIC WATER SYSTEM
Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.
General Contact
Treatment Plant
Recommended water filters for CINCINNATI
Filters matched to the specific contaminants in this water supply.
Reverse Osmosis or NSF P473 certified carbon
$80-$750Activated carbon and RO are the only technologies proven to remove PFAS at certified levels.
Carbon block (NSF/ANSI 42 + 53)
$40-$750Activated carbon is highly effective for disinfection byproducts like TTHM and HAA5.
Reverse Osmosis
$249-$750Arsenic is most effectively removed by reverse osmosis. Some specialized adsorptive filters also work.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
Score breakdown
This utility's overall score of 61/100 breaks down across five weighted components. Read the full methodology →
Contaminants detected — international standards comparison
Every contaminant detected, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal (the strictest US benchmark). Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Total trihalomethanes (TTHMs) Disinfection byproduct |
38.1 ppb | 0.15 | 80.0 | 100 | — | — | — | 254× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
11.6 ppb | 0.06 | — | — | — | — | — | 193× over |
| Bromodichloromethane Disinfection byproduct |
10.5 ppb | 0.06 | — | — | — | — | — | 175× over |
| Dibromochloromethane Disinfection byproduct |
11.3 ppb | 0.1 | — | — | — | — | — | 113× over |
| Dibromoacetic acid Disinfection byproduct |
3.07 ppb | 0.03 | — | — | — | — | — | 102× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
8.17 ppb | 0.1 | 60.0 | 60 | — | — | — | 82× over |
| Arsenic Heavy metal |
0.233 ppb | 0.004 | 10.0 | 10 | 10 | 0.004 | — | 58× over |
| Chloroform Disinfection byproduct |
11.2 ppb | 0.4 | — | — | — | — | — | 28× over |
| Dichloroacetic acid Disinfection byproduct |
2.87 ppb | 0.2 | — | — | — | — | — | 14× over |
| Bromoform Disinfection byproduct |
4.94 ppb | 0.5 | — | — | — | — | — | 9.9× over |
| Trichloroacetic acid Disinfection byproduct |
0.87 ppb | 0.1 | — | — | — | — | — | 8.7× over |
| Chromium (hexavalent) Heavy metal |
0.117 ppb | 0.02 | — | — | — | — | — | 5.9× over |
| Nitrate and nitrite Inorganic |
0.779 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 5.6× over |
| Nitrate Inorganic |
0.758 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 5.4× over |
| Perfluorooctane sulfonate (PFOS) PFAS |
0.736 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | 2.5× over |
| 1,4-Dioxane Semi-volatile organic compound |
0.401 ppb | 0.35 | — | — | 50 | 1 | — | 1.1× over |
| Chlorate Disinfection byproduct |
15.3 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Molybdenum Other |
2.47 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
23.3 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
1.09 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
0.382 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.433 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Perfluorobutanoic Acid (PFBA) PFAS |
1.72 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
0.557 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.193 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.823 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines (4th ed.), California OEHHA PHGs, EWG Tap Water Database.
CINCINNATI PUBLIC WATER SYSTEM service area
This water system serves 1 community in Hamilton County, Ohio. Click any city for its dedicated tap water quality page.
Find the right filter for CINCINNATI water
Browse filter categories by water-quality concern. Each option below is NSF-certified for the matched contaminant type.