Water Quality Report · Updated May 12, 2026

HAMILTON PUBLIC WATER SYSTEM

Serving 62,447 residents in FAIRFIELD, Ohio .

National rank 97th percentile
Ohio rank 100th percentile
Data confidence Medium
Quick answer

HAMILTON PUBLIC WATER SYSTEM delivers tap water graded B (81/100) by TapWaterSafety.org. The utility serves approximately 62,447 residents in FAIRFIELD, Ohio using groundwater. The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Chromium (hexavalent) significantly above health guideline; Dibromoacetic acid significantly above health guideline.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?
62,447
People served
1
City served
22
Contaminants detected
7
Above health guidelines
0
EPA violations (5 yr)

Is FAIRFIELD tap water safe to drink?

HAMILTON PUBLIC WATER SYSTEM delivers tap water that earns a grade of B (81/100) from TapWaterSafety.org — a good rating, with only minor concerns relative to health-based guidelines.

The utility serves 62,447 residents in FAIRFIELD, drawing from groundwater.

Public testing data identifies 7 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA9), Chromium (hexavalent), Dibromoacetic acid, Chlorite, Haloacetic acids (HAA5), Nitrate and nitrite, Nitrate. 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 FAIRFIELD residents

Top concerns in this water

Based on the most recent EPA and EWG data, these are the most significant water quality issues for HAMILTON PUBLIC WATER SYSTEM.

Haloacetic acids (HAA9) significantly above health guideline

Moderate concern

Haloacetic acids (HAA9) detected at 1.1 ppb, 18x above the EWG health guideline of 0.06 ppb.

Chromium (hexavalent) significantly above health guideline

Moderate concern

Chromium (hexavalent) detected at 0.33 ppb, 17x above the EWG health guideline of 0.02 ppb.

Dibromoacetic acid significantly above health guideline

Moderate concern

Dibromoacetic acid detected at 0.517 ppb, 17x above the EWG health guideline of 0.03 ppb.

Contact HAMILTON PUBLIC WATER SYSTEM

Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.

Recommended water filters for FAIRFIELD

Filters matched to the specific contaminants in this water supply.

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 81/100 breaks down across five weighted components. Read the full methodology →

Health Guideline Performance
23 / 40
Legal Compliance
20 / 20
High-Risk Contaminants
20 / 20
Compliance History
10 / 10
Source Water Vulnerability
8 / 10

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
Haloacetic acids (HAA9)
Disinfection byproduct
1.1 ppb 0.06 18× over
Chromium (hexavalent)
Heavy metal
0.33 ppb 0.02 17× over
Dibromoacetic acid
Disinfection byproduct
0.517 ppb 0.03 17× over
Chlorite
Disinfection byproduct
520.1 ppb 50.0 1000.0 10× over
Haloacetic acids (HAA5)
Disinfection byproduct
0.567 ppb 0.1 60.0 60 5.7× over
Nitrate and nitrite
Inorganic
0.62 ppm 0.14 10.0 11.3 11.3 10 4.4× over
Nitrate
Inorganic
0.592 ppm 0.14 10.0 11.3 11.3 10 4.2× over
Total trihalomethanes (TTHMs)
Disinfection byproduct
0.1 ppb 0.15 80.0 100 Below guideline
1,4-Dioxane
Semi-volatile organic compound
0.177 ppb 0.35 50 1 Below guideline
Chlorate
Disinfection byproduct
51.9 ppb 210.0 Below guideline
Bromoform
Disinfection byproduct
0.0857 ppb 0.5 Below guideline
Barium
Heavy metal
43.1 ppb 700.0 2000.0 1300 2000 Below guideline
Chloroform
Disinfection byproduct
0.0243 ppb 0.4 Below guideline
Molybdenum
Other
2.35 ppb 40.0 Below guideline
Vanadium
Other
0.41 ppb 21.0 Below guideline
Manganese
Heavy metal
0.725 ppb 100.0 50 80 Below guideline
Monochloroacetic acid
Disinfection byproduct
0.333 ppb 53.0 Below guideline
Perfluorobutane sulfonate (PFBS)
PFAS
0.3 ppt 2000.0 Below guideline
Strontium
Radiological
0.13 ppb 1500.0 Below guideline
Chlorodifluoromethane
Other
0.118 ppb Below guideline
Cyanide
Inorganic
5.5 ppb 200.0 50 70 150 Below guideline
Fluoride
Inorganic
0.82 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.

HAMILTON PUBLIC WATER SYSTEM service area

This water system serves 1 community in Butler County, Ohio. Click any city for its dedicated tap water quality page.

About this water system

Public Water System ID
OH0904012
Owner type
Local government
Source water
Groundwater
Service connections
24,433
Service area
FAIRFIELD, Butler County, Ohio