North Dakota Tap Water Quality Report
3 cities analyzed • 121,828 people served
Updated March 2026 • Data from EWG & EPA SDWIS
Most Common Contaminants in North Dakota
| Contaminant | Found In | % of Cities |
|---|---|---|
| Bromodichloromethane carcinogen | 3 of 3 | 100% |
| Chloroform carcinogen | 3 of 3 | 100% |
| Dibromoacetic acid | 3 of 3 | 100% |
| Dibromochloromethane carcinogen | 3 of 3 | 100% |
| Dichloroacetic acid carcinogen | 3 of 3 | 100% |
| Haloacetic acids (HAA5) carcinogen | 3 of 3 | 100% |
| Total trihalomethanes (TTHMs) carcinogen | 3 of 3 | 100% |
| Trichloroacetic acid carcinogen | 3 of 3 | 100% |
| Lithium* | 2 of 3 | 67% |
| Bromate carcinogen | 1 of 3 | 33% |
City-by-City Water Quality Rankings
Ranked by number of contaminants above EWG health guidelines (most to fewest).
Recommended Filtration for North Dakota
Based on the most common contaminants found across North Dakota (Bromodichloromethane, Chloroform, Dibromoacetic acid), we recommend a reverse osmosis (RO) system for comprehensive contaminant removal.
Echo RO System
Removes up to 99.9% of contaminants. The gold standard for drinking water in North Dakota homes.
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Protect every tap in your home from chlorine, VOCs, and disinfection byproducts.
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Shop Hydrogen FlaskFrequently Asked Questions
Is North Dakota tap water safe to drink?
Water quality varies significantly across North Dakota. Of the 3 cities analyzed, the average city has 10.7 contaminants above EWG health guidelines. The best water quality was found in Williston. We recommend checking your specific city's report for detailed information.
What city has the best water in North Dakota?
Based on our analysis, Williston has the fewest contaminants above EWG health guidelines in North Dakota, with 8 above guideline levels.
What city has the worst water in North Dakota?
Based on our analysis, Null has the most contaminants above EWG health guidelines in North Dakota, with 13 above guideline levels.
What's the best water filter for North Dakota residents?
For most North Dakota households, we recommend a reverse osmosis (RO) system for drinking water and a whole-home filter for showers and baths. The specific recommendation depends on your city's contaminant profile — check your city's report for personalized guidance.
National Water Quality Reports
Data sources: Environmental Working Group (EWG) Tap Water Database, U.S. EPA Safe Drinking Water Information System (SDWIS)
Last updated: March 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.
