Tap Water Quality Report
Tap water quality in Duluth, Minnesota
Tap water in Duluth, Minnesota receives a grade of D (67/100) from TapWaterSafety.org. It's served by Duluth. The most significant water quality concerns are: Haloacetic acids (HAA9) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in Duluth's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving Duluth.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 11.4 ppb, 190x above the EWG health guideline of 0.06 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 12.3 ppb, 123x above the EWG health guideline of 0.1 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 15.6 ppb, 104x above the EWG health guideline of 0.15 ppb.
Recommended filters for Duluth
Filters matched to the specific contaminants in Duluth's water supply.
Carbon block (NSF/ANSI 42 + 53)
$40-$750Activated carbon is highly effective for disinfection byproducts like TTHM and HAA5.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
All contaminants detected in Duluth's tap water
Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. 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 |
11.4 ppb | 0.06 | — | — | — | — | — | 190× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
12.3 ppb | 0.1 | 60.0 | 60 | — | — | — | 123× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
15.6 ppb | 0.15 | 80.0 | 100 | — | — | — | 104× over |
| Bromodichloromethane Disinfection byproduct |
2.94 ppb | 0.06 | — | — | — | — | — | 49× over |
| Trichloroacetic acid Disinfection byproduct |
4.76 ppb | 0.1 | — | — | — | — | — | 48× over |
| Dichloroacetic acid Disinfection byproduct |
7.51 ppb | 0.2 | — | — | — | — | — | 38× over |
| Chloroform Disinfection byproduct |
12.4 ppb | 0.4 | — | — | — | — | — | 31× over |
| Nitrate Inorganic |
0.373 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 2.7× over |
| Chromium (hexavalent) Heavy metal |
0.0468 ppb | 0.02 | — | — | — | — | — | 2.3× over |
| Dibromochloromethane Disinfection byproduct |
0.231 ppb | 0.1 | — | — | — | — | — | 2.3× over |
| Chlorate Disinfection byproduct |
39.1 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
0.404 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Vanadium Other |
0.0325 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Perfluorobutanoic Acid (PFBA) PFAS |
0.49 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.0265 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.722 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, California OEHHA PHGs, EWG Tap Water Database.
Treatment plant contact info
For service issues, water quality concerns, or to request a Consumer Confidence Report from Duluth.