Water Quality Report · Updated May 12, 2026
DAYTON PUBLIC WATER SYSTEM
DAYTON PUBLIC WATER SYSTEM delivers tap water graded D (61/100) by TapWaterSafety.org. The utility serves approximately 141,407 residents in DAYTON, Ohio using surface water. The most significant water quality concerns are: PFAS contamination; Perfluorohexane sulfonate (PFHXS) significantly above health guideline; Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline. For questions, the utility can be reached at 937-333-6099.
Is DAYTON tap water safe to drink?
DAYTON 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 141,407 residents in DAYTON, drawing from surface water.
Public testing data identifies 15 contaminants in this water above EWG's health-based guidelines, including: Perfluorohexane sulfonate (PFHXS), Haloacetic acids (HAA9), Total trihalomethanes (TTHMs), Bromodichloromethane, Dibromoacetic acid, Dibromochloromethane, Haloacetic acids (HAA5), Chloroform, Dichloroacetic acid, Perfluorooctane sulfonate (PFOS), Nitrate, Nitrate and nitrite, Chromium (hexavalent), Bromoform, Trichloroacetic acid. 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 DAYTON residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for DAYTON 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.
Perfluorohexane sulfonate (PFHXS) significantly above health guideline
Moderate concernPerfluorohexane sulfonate (PFHXS) detected at 3.91 ppt, 3914x above the EWG health guideline of 0.001 ppt.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 10.3 ppb, 172x above the EWG health guideline of 0.06 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 22.8 ppb, 152x above the EWG health guideline of 0.15 ppb.
Contact DAYTON 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 DAYTON
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.
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 |
|---|---|---|---|---|---|---|---|---|
| Perfluorohexane sulfonate (PFHXS) PFAS |
3.91 ppt | 0.001 | 10.0 | — | — | — | — | 3914× over |
| Haloacetic acids (HAA9) Disinfection byproduct |
10.3 ppb | 0.06 | — | — | — | — | — | 172× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
22.8 ppb | 0.15 | 80.0 | 100 | — | — | — | 152× over |
| Bromodichloromethane Disinfection byproduct |
6.54 ppb | 0.06 | — | — | — | — | — | 109× over |
| Dibromoacetic acid Disinfection byproduct |
2.38 ppb | 0.03 | — | — | — | — | — | 79× over |
| Dibromochloromethane Disinfection byproduct |
6.02 ppb | 0.1 | — | — | — | — | — | 60× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
5.51 ppb | 0.1 | 60.0 | 60 | — | — | — | 55× over |
| Chloroform Disinfection byproduct |
6.76 ppb | 0.4 | — | — | — | — | — | 17× over |
| Dichloroacetic acid Disinfection byproduct |
2.81 ppb | 0.2 | — | — | — | — | — | 14× over |
| Perfluorooctane sulfonate (PFOS) PFAS |
2.64 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | 8.8× over |
| Nitrate Inorganic |
0.767 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 5.5× over |
| Nitrate and nitrite Inorganic |
0.705 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 5.0× over |
| Chromium (hexavalent) Heavy metal |
0.0823 ppb | 0.02 | — | — | — | — | — | 4.1× over |
| Bromoform Disinfection byproduct |
1.74 ppb | 0.5 | — | — | — | — | — | 3.5× over |
| Trichloroacetic acid Disinfection byproduct |
0.333 ppb | 0.1 | — | — | — | — | — | 3.3× over |
| 1,4-Dioxane Semi-volatile organic compound |
0.185 ppb | 0.35 | — | — | 50 | 1 | — | Below guideline |
| Molybdenum Other |
4.61 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
73.7 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Manganese Heavy metal |
7.55 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
1.3 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
1.79 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
1.73 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.531 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
0.075 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| 2-Methoxyethanol Other |
3.25 ppb | — | — | — | — | — | — | Below guideline |
| cis-1,2-Dichloroethylene Volatile organic compound |
0.0974 ppb | — | 70.0 | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.878 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.
DAYTON PUBLIC WATER SYSTEM service area
This water system serves 1 community in Montgomery County, Ohio. Click any city for its dedicated tap water quality page.
Find the right filter for DAYTON water
Browse filter categories by water-quality concern. Each option below is NSF-certified for the matched contaminant type.