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Tap water quality report

Thief River Falls, MN

EPA monitoring detected 13 contaminants across the 2 water suppliers serving Thief River Falls. A detection doesn't automatically mean the water is unsafe — see the level at the main supplier for each below, with its EPA source and period.

2
water suppliers
8,751
people served
13
contaminants found
Minnesota rankings Lead in Minnesota PFAS in Minnesota

What was found in Thief River Falls's water

The level at the city's main supplier, the highest level anywhere in the city, the EPA limit for each, and where every figure comes from.

ContaminantLevel vs EPA limitSuppliersSource
Fluoride
1140 µg/L 28%
of the EPA limit 4000 µg/L
Main supplier: Thief River Falls · 8,701 people · 2019
2/2 SYR4
Nitrate-Nitrite
650 µg/L 6.5%
of the EPA limit 10000 µg/L
Main supplier: Thief River Falls · 8,701 people · 2019
1/2 SYR4
Cyanide
470 µg/L 235%
of the EPA limit, at the 95th percentile of samples — 200 µg/L
Highest in the city: Aaseby Court · 50 people · 2019
1/2 SYR4
Barium
97.7 µg/L 4.9%
of the EPA limit 2000 µg/L
Highest in the city: Aaseby Court · 50 people · 2018
1/2 SYR4
Copper
76.35 µg/L 5.9%
of the EPA limit 1300 µg/L
Main supplier: Thief River Falls · 8,701 people · 2019
2/2 SYR4
Chloroform
74.65 µg/L
No EPA limit set
Main supplier: Thief River Falls · 8,701 people · 2019
1/2 SYR4
Dichloroacetic Acid
50.55 µg/L
No EPA limit set
Main supplier: Thief River Falls · 8,701 people · 2019
1/2 SYR4
Lead
9.9 µg/L 66%
of the EPA limit 15 µg/L
Main supplier: Thief River Falls · 8,701 people · 2019
2/2 SYR4
Trichloroacetic Acid
6.86 µg/L
No EPA limit set
Main supplier: Thief River Falls · 8,701 people · 2019
1/2 SYR4
Monochloroacetic Acid
5.2 µg/L
No EPA limit set
Main supplier: Thief River Falls · 8,701 people · 2019
1/2 SYR4
Bromodichloromethane
5 µg/L
No EPA limit set
Main supplier: Thief River Falls · 8,701 people · 2019
1/2 SYR4
Pfba
0.0120 µg/L
No EPA limit set
Main supplier: Thief River Falls · 8,701 people · 2023
1/2 UCMR-5
Lead
0.0070 mg/L 47%
of the EPA limit 0.0150 mg/L
Main supplier: Thief River Falls · 8,701 people · 2023
2/2 LCR
Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the 95th percentile of the system's samples — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately. These are the utilities' own EPA-reported results, not a city-wide average. A detection means the lab measured the substance — it isn't the same as exceeding a legal limit. Hover a source tag to see the EPA program and years behind each figure.

Water suppliers serving Thief River Falls

SupplierPopulation served
Thief River Falls 8,701
Aaseby Court 50

Frequently asked questions about Thief River Falls tap water

Is Thief River Falls tap water safe to drink?

EPA testing detected 13 contaminants in the water serving Thief River Falls. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.

How many water suppliers serve Thief River Falls?

2 public water suppliers report drinking-water monitoring for Thief River Falls, Minnesota to the EPA. Each is listed above with its population served.

What contaminants are in Thief River Falls's water?

The contaminants EPA monitoring detected in Thief River Falls include Fluoride, Nitrate-Nitrite, Cyanide, Barium, Copper. The full list, with the level at the main supplier and the data source, is in the table above.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.