We analyzed tap water quality data for hundreds of cities in Mississippi 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EPA legal limits, many health experts — including the Environmental Working Group — argue that these legal limits are outdated and don't reflect current scientific understanding of safe exposure levels.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
Coahoma, Mississippi
Coahoma has 10 contaminants exceeding EWG health guidelines out of 15 detected — significantly above the national average. Multiple known carcinogens were found at levels of concern.
See full Coahoma water report →University, Mississippi
University has 9 contaminants exceeding EWG health guidelines out of 15 total detected, placing it among the most concerning water supplies analyzed.
See full University water report →Washington, Mississippi
Washington has 9 contaminants exceeding EWG health guidelines out of 14 total detected, placing it among the most concerning water supplies analyzed.
See full Washington water report →Renova, Mississippi
Renova has 9 contaminants exceeding EWG health guidelines out of 13 total detected, placing it among the most concerning water supplies analyzed.
See full Renova water report →Pocahontas, Mississippi
Pocahontas has 9 contaminants exceeding EWG health guidelines out of 12 total detected, placing it among the most concerning water supplies analyzed.
See full Pocahontas water report →Jackson, Mississippi
Jackson has 8 contaminants exceeding EWG health guidelines out of 18 total detected, placing it among the most concerning water supplies analyzed.
See full Jackson water report →Holly Springs, Mississippi
Holly Springs has 8 contaminants exceeding EWG health guidelines out of 11 total detected, placing it among the most concerning water supplies analyzed.
See full Holly Springs water report →State Line, Mississippi
State Line has 8 contaminants exceeding EWG health guidelines out of 11 total detected, placing it among the most concerning water supplies analyzed.
See full State Line water report →Ackerman, Mississippi
Ackerman has 8 contaminants exceeding EWG health guidelines out of 9 total detected, placing it among the most concerning water supplies analyzed.
See full Ackerman water report →Southaven, Mississippi
Southaven has 7 contaminants exceeding EWG health guidelines out of 15 total detected, placing it among the most concerning water supplies analyzed.
See full Southaven water report →Oxford, Mississippi
Oxford has 7 contaminants exceeding EWG health guidelines out of 14 total detected, placing it among the most concerning water supplies analyzed.
See full Oxford water report →Natchez, Mississippi
Natchez has 7 contaminants exceeding EWG health guidelines out of 14 total detected, placing it among the most concerning water supplies analyzed.
See full Natchez water report →Olive Branch, Mississippi
Olive Branch has 7 contaminants exceeding EWG health guidelines out of 13 total detected, placing it among the most concerning water supplies analyzed.
See full Olive Branch water report →Pass Christian, Mississippi
Pass Christian has 7 contaminants exceeding EWG health guidelines out of 12 total detected, placing it among the most concerning water supplies analyzed.
See full Pass Christian water report →Lucedale, Mississippi
Lucedale has 7 contaminants exceeding EWG health guidelines out of 10 total detected, placing it among the most concerning water supplies analyzed.
See full Lucedale water report →Bude, Mississippi
Bude has 7 contaminants exceeding EWG health guidelines out of 9 total detected, placing it among the most concerning water supplies analyzed.
See full Bude water report →Nesbit, Mississippi
Nesbit has 7 contaminants exceeding EWG health guidelines out of 7 total detected, placing it among the most concerning water supplies analyzed.
See full Nesbit water report →Mccarley, Mississippi
Mccarley has 7 contaminants exceeding EWG health guidelines out of 7 total detected, placing it among the most concerning water supplies analyzed.
See full Mccarley water report →Glen, Mississippi
Glen has 6 contaminants exceeding EWG health guidelines out of 18 total detected, placing it among the most concerning water supplies analyzed.
See full Glen water report →Gautier, Mississippi
Gautier has 6 contaminants exceeding EWG health guidelines out of 17 total detected, placing it among the most concerning water supplies analyzed.
See full Gautier water report →Brookhaven, Mississippi
Brookhaven has 6 contaminants exceeding EWG health guidelines out of 16 total detected, placing it among the most concerning water supplies analyzed.
See full Brookhaven water report →Pascagoula, Mississippi
Pascagoula has 6 contaminants exceeding EWG health guidelines out of 15 total detected, placing it among the most concerning water supplies analyzed.
See full Pascagoula water report →Raymond, Mississippi
Raymond has 6 contaminants exceeding EWG health guidelines out of 15 total detected, placing it among the most concerning water supplies analyzed.
See full Raymond water report →Hernando, Mississippi
Hernando has 6 contaminants exceeding EWG health guidelines out of 13 total detected, placing it among the most concerning water supplies analyzed.
See full Hernando water report →Vicksburg, Mississippi
Vicksburg has 6 contaminants exceeding EWG health guidelines out of 12 total detected, placing it among the most concerning water supplies analyzed.
See full Vicksburg water report →What We Found: Key Patterns
The most frequently detected contaminants exceeding health guidelines across these cities are Haloacetic acids (HAA5), Total trihalomethanes (TTHMs), 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, 183 contaminant readings exceed EWG health guidelines, but only 0 exceed EPA legal limits. This gap of 183 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 | Coahoma | MS | 15 | 10 | 0 | 299 |
| 2 | University | MS | 15 | 9 | 0 | 22,874 |
| 3 | Washington | MS | 14 | 9 | 0 | 7,532 |
| 4 | Renova | MS | 13 | 9 | 0 | 1,336 |
| 5 | Pocahontas | MS | 12 | 9 | 0 | 713 |
| 6 | Jackson | MS | 18 | 8 | 0 | 188,723 |
| 7 | Holly Springs | MS | 11 | 8 | 0 | 9,868 |
| 8 | State Line | MS | 11 | 8 | 0 | 1,983 |
| 9 | Ackerman | MS | 9 | 8 | 0 | 1,742 |
| 10 | Southaven | MS | 15 | 7 | 0 | 55,782 |
| 11 | Oxford | MS | 14 | 7 | 0 | 25,000 |
| 12 | Natchez | MS | 14 | 7 | 0 | 15,792 |
| 13 | Olive Branch | MS | 13 | 7 | 0 | 53,238 |
| 14 | Pass Christian | MS | 12 | 7 | 0 | 9,921 |
| 15 | Lucedale | MS | 10 | 7 | 0 | 3,134 |
| 16 | Bude | MS | 9 | 7 | 0 | 0 |
| 17 | Nesbit | MS | 7 | 7 | 0 | 5,436 |
| 18 | Mccarley | MS | 7 | 7 | 0 | 660 |
| 19 | Glen | MS | 18 | 6 | 0 | 15,000 |
| 20 | Gautier | MS | 17 | 6 | 0 | 19,776 |
| 21 | Brookhaven | MS | 16 | 6 | 0 | 12,513 |
| 22 | Pascagoula | MS | 15 | 6 | 0 | 22,686 |
| 23 | Raymond | MS | 15 | 6 | 0 | 12,218 |
| 24 | Hernando | MS | 13 | 6 | 0 | 14,309 |
| 25 | Vicksburg | MS | 12 | 6 | 0 | 29,238 |
Frequently Asked Questions
What city has the worst tap water in Mississippi?
Based on 2026 data, Coahoma, MS 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.
