We analyzed tap water quality data for hundreds of cities in Michigan to identify the 25 with the most contaminants exceeding health guidelines. This ranking is based on 2026 data from the EPA and EWG databases.
While all public water systems must meet EPA legal limits, many health experts — including the Environmental Working Group — argue that these legal limits are outdated and don't reflect current scientific understanding of safe exposure levels. The cities below have the widest gap between what's in their water and what's considered safe by modern health standards.
Rankings at a Glance
Portland, Michigan
Portland has 14 contaminants exceeding EWG health guidelines out of 25 detected — significantly above the national average. Multiple known carcinogens were found at levels of concern.
See full Portland water report →Temperance, Michigan
Temperance has 14 contaminants exceeding EWG health guidelines out of 23 detected — significantly above the national average. Multiple known carcinogens were found at levels of concern.
See full Temperance water report →Ann Arbor, Michigan
Ann Arbor has 11 contaminants exceeding EWG health guidelines out of 24 detected — significantly above the national average. Multiple known carcinogens were found at levels of concern.
See full Ann Arbor water report →Michiana, Michigan
Michiana has 10 contaminants exceeding EWG health guidelines out of 19 detected — significantly above the national average. Multiple known carcinogens were found at levels of concern.
See full Michiana water report →Kalamazoo, Michigan
Kalamazoo has 9 contaminants exceeding EWG health guidelines out of 25 total detected, placing it among the most concerning water supplies analyzed.
See full Kalamazoo water report →Portage, Michigan
Portage has 9 contaminants exceeding EWG health guidelines out of 21 total detected, placing it among the most concerning water supplies analyzed.
See full Portage water report →Independence Township, Michigan
Independence Township has 9 contaminants exceeding EWG health guidelines out of 19 total detected, placing it among the most concerning water supplies analyzed.
See full Independence Township water report →Monroe, Michigan
Monroe has 9 contaminants exceeding EWG health guidelines out of 17 total detected, placing it among the most concerning water supplies analyzed.
See full Monroe water report →Dundee, Michigan
Dundee has 9 contaminants exceeding EWG health guidelines out of 17 total detected, placing it among the most concerning water supplies analyzed.
See full Dundee water report →Petersburg, Michigan
Petersburg has 9 contaminants exceeding EWG health guidelines out of 17 total detected, placing it among the most concerning water supplies analyzed.
See full Petersburg water report →Holland, Michigan
Holland has 9 contaminants exceeding EWG health guidelines out of 15 total detected, placing it among the most concerning water supplies analyzed.
See full Holland water report →Zeeland, Michigan
Zeeland has 9 contaminants exceeding EWG health guidelines out of 15 total detected, placing it among the most concerning water supplies analyzed.
See full Zeeland water report →Mount Clemens, Michigan
Mount Clemens has 8 contaminants exceeding EWG health guidelines out of 18 total detected, placing it among the most concerning water supplies analyzed.
See full Mount Clemens water report →Niles, Michigan
Niles has 8 contaminants exceeding EWG health guidelines out of 16 total detected, placing it among the most concerning water supplies analyzed.
See full Niles water report →Mt Pleasant, Michigan
Mt Pleasant has 8 contaminants exceeding EWG health guidelines out of 15 total detected, placing it among the most concerning water supplies analyzed.
See full Mt Pleasant water report →St. Joseph, Michigan
St. Joseph has 8 contaminants exceeding EWG health guidelines out of 15 total detected, placing it among the most concerning water supplies analyzed.
See full St. Joseph water report →Clare, Michigan
Clare has 8 contaminants exceeding EWG health guidelines out of 14 total detected, placing it among the most concerning water supplies analyzed.
See full Clare water report →Bronson, Michigan
Bronson has 8 contaminants exceeding EWG health guidelines out of 11 total detected, placing it among the most concerning water supplies analyzed.
See full Bronson water report →Adrian, Michigan
Adrian has 7 contaminants exceeding EWG health guidelines out of 17 total detected, placing it among the most concerning water supplies analyzed.
See full Adrian water report →Wyoming, Michigan
Wyoming has 7 contaminants exceeding EWG health guidelines out of 16 total detected, placing it among the most concerning water supplies analyzed.
See full Wyoming water report →Jenison, Michigan
Jenison has 7 contaminants exceeding EWG health guidelines out of 16 total detected, placing it among the most concerning water supplies analyzed.
See full Jenison water report →Kentwood, Michigan
Kentwood has 7 contaminants exceeding EWG health guidelines out of 16 total detected, placing it among the most concerning water supplies analyzed.
See full Kentwood water report →Grandville, Michigan
Grandville has 7 contaminants exceeding EWG health guidelines out of 16 total detected, placing it among the most concerning water supplies analyzed.
See full Grandville water report →Hudsonville, Michigan
Hudsonville has 7 contaminants exceeding EWG health guidelines out of 16 total detected, placing it among the most concerning water supplies analyzed.
See full Hudsonville water report →Wyandotte, Michigan
Wyandotte has 7 contaminants exceeding EWG health guidelines out of 14 total detected, placing it among the most concerning water supplies analyzed.
See full Wyandotte water report →What We Found: Key Patterns
The most frequently detected contaminants exceeding health guidelines across these cities are Total trihalomethanes (TTHMs), Haloacetic acids (HAA5), Haloacetic acids (HAA9). These appear repeatedly across different water systems and regions.
Water quality varies significantly even within the same state, driven by local geology, agricultural activity, and industrial proximity.
Across all ranked cities, 218 contaminant readings exceed EWG health guidelines, but only 1 exceed EPA legal limits. This gap of 217 highlights how legal standards may not fully protect public health — EPA limits haven't been updated for many contaminants in decades.
Full Rankings Table
| Rank | City | State | Detected | Above Guidelines | Above Legal | People Served |
|---|---|---|---|---|---|---|
| 1 | Portland | MI | 25 | 14 | 0 | 3,883 |
| 2 | Temperance | MI | 23 | 14 | 0 | 33,816 |
| 3 | Ann Arbor | MI | 24 | 11 | 0 | 118,017 |
| 4 | Michiana | MI | 19 | 10 | 0 | 182 |
| 5 | Kalamazoo | MI | 25 | 9 | 0 | 192,992 |
| 6 | Portage | MI | 21 | 9 | 0 | 46,292 |
| 7 | Independence Township | MI | 19 | 9 | 0 | 11,790 |
| 8 | Monroe | MI | 17 | 9 | 0 | 48,664 |
| 9 | Dundee | MI | 17 | 9 | 1 | 4,250 |
| 10 | Petersburg | MI | 17 | 9 | 0 | 1,115 |
| 11 | Holland | MI | 15 | 9 | 0 | 36,542 |
| 12 | Zeeland | MI | 15 | 9 | 0 | 8,328 |
| 13 | Mount Clemens | MI | 18 | 8 | 0 | 18,405 |
| 14 | Niles | MI | 16 | 8 | 0 | 14,215 |
| 15 | Mt Pleasant | MI | 15 | 8 | 0 | 21,688 |
| 16 | St. Joseph | MI | 15 | 8 | 0 | 0 |
| 17 | Clare | MI | 14 | 8 | 0 | 0 |
| 18 | Bronson | MI | 11 | 8 | 0 | 0 |
| 19 | Adrian | MI | 17 | 7 | 0 | 23,663 |
| 20 | Wyoming | MI | 16 | 7 | 0 | 72,125 |
| 21 | Jenison | MI | 16 | 7 | 0 | 41,086 |
| 22 | Kentwood | MI | 16 | 7 | 0 | 36,072 |
| 23 | Grandville | MI | 16 | 7 | 0 | 15,948 |
| 24 | Hudsonville | MI | 16 | 7 | 0 | 7,708 |
| 25 | Wyandotte | MI | 14 | 7 | 0 | 25,883 |
Frequently Asked Questions
What city has the worst tap water in Michigan?
Based on 2026 data, Portland, MI has the most contaminants exceeding EWG health guidelines among the cities we analyzed.
How are cities ranked in this report?
Cities are ranked by the number of contaminants exceeding EWG health guidelines. These guidelines are typically stricter than EPA legal limits and reflect current scientific research on safe exposure levels.
Is my tap water safe if my city isn't on this list?
Not necessarily. Even cities not on this list may have contaminants of concern. We recommend checking your specific water quality using our free water scan tool.
What's the best water filter for contaminated water?
A reverse osmosis (RO) system is the most effective for removing the widest range of contaminants. For whole-home protection, a combination of RO for drinking water and a whole-home filter for showers and baths is recommended.
Related Reports
Data sources: Environmental Working Group (EWG) Tap Water Database, U.S. EPA Safe Drinking Water Information System (SDWIS)
Last updated: April 2026
Methodology: Contaminant levels are compared against both EPA legal limits (Maximum Contaminant Levels) and EWG health guidelines, which are often stricter and based on the latest scientific research.
