Water Quality Report · Updated May 12, 2026

TROY

Serving 85,854 residents in TROY, Michigan .

National rank 94th percentile
Michigan rank 48th percentile
Data confidence Medium
Quick answer

TROY delivers tap water graded B (78/100) by TapWaterSafety.org. The utility serves approximately 85,854 residents in TROY, Michigan using surface water (purchased). The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline. For questions, the utility can be reached at 248-524-1520.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?
85,854
People served
1
City served
8
Contaminants detected
5
Above health guidelines
0
EPA violations (5 yr)

Is TROY tap water safe to drink?

TROY delivers tap water that earns a grade of B (78/100) from TapWaterSafety.org — a good rating, with only minor concerns relative to health-based guidelines.

The utility serves 85,854 residents in TROY, drawing from surface water (purchased).

Public testing data identifies 5 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA9), Total trihalomethanes (TTHMs), Haloacetic acids (HAA5), Chromium (hexavalent), 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.

Top concerns in this water

Based on the most recent EPA and EWG data, these are the most significant water quality issues for TROY.

Haloacetic acids (HAA9) significantly above health guideline

Moderate concern

Haloacetic acids (HAA9) detected at 21.6 ppb, 361x above the EWG health guideline of 0.06 ppb.

Total trihalomethanes (TTHMs) significantly above health guideline

Moderate concern

Total trihalomethanes (TTHMs) detected at 32.3 ppb, 216x above the EWG health guideline of 0.15 ppb.

Haloacetic acids (HAA5) significantly above health guideline

Moderate concern

Haloacetic acids (HAA5) detected at 16.9 ppb, 169x above the EWG health guideline of 0.1 ppb.

Contact TROY

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

Recommended water filters for TROY

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 78/100 breaks down across five weighted components. Read the full methodology →

Health Guideline Performance
21 / 40
Legal Compliance
20 / 20
High-Risk Contaminants
20 / 20
Compliance History
10 / 10
Source Water Vulnerability
7 / 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
21.6 ppb 0.06 361× over
Total trihalomethanes (TTHMs)
Disinfection byproduct
32.3 ppb 0.15 80.0 100 216× over
Haloacetic acids (HAA5)
Disinfection byproduct
16.9 ppb 0.1 60.0 60 169× over
Chromium (hexavalent)
Heavy metal
0.138 ppb 0.02 6.9× over
Nitrate*
Inorganic
0.523 ppm 0.14 10.0 11.3 11.3 10 3.7× over
Vanadium
Other
0.163 ppb 21.0 Below guideline
Strontium
Radiological
0.1 ppb 1500.0 Below guideline
Fluoride*
Inorganic
0.62 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.

TROY service area

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

About this water system

Public Water System ID
MI0006690
Owner type
Local government
Source water
Surface water (purchased)
Service connections
24,300
Service area
TROY, Oakland County, Michigan