What was found in Cass Lake'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.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate | 2000 µg/L 20% of the EPA limit 10000 µg/L Main supplier: NORTHSIDE · 2,086 people · 2019 | 5/8 | SYR4 |
| Fluoride | 1211 µg/L 30% of the EPA limit 4000 µg/L Highest in the city: Cass Lake · 691 people · 2019 | 6/8 | SYR4 |
| Lead | 928.8 µg/L 6192% of the EPA limit, at the 95th percentile of samples — 15 µg/L Main supplier: NORTHSIDE · 2,086 people · 2019 | 8/8 | SYR4 |
| Copper | 779.45 µg/L 60% of the EPA limit 1300 µg/L Main supplier: NORTHSIDE · 2,086 people · 2019
Highest in the city: 861.8 µg/L — INGER · 186 people · 2019 | 8/8 | SYR4 |
| Barium | 8.94 µg/L 0.4% of the EPA limit 2000 µg/L Main supplier: NORTHSIDE · 2,086 people · 2018
Highest in the city: 174 µg/L — INGER · 186 people · 2018 | 7/8 | SYR4 |
| Nitrate-Nitrite | 60 µg/L 0.6% of the EPA limit 10000 µg/L Highest in the city: Cass Lake · 691 people · 2019 | 1/8 | SYR4 |
| Gross Beta Particle Activity | 13.74 pCi/L No EPA limit set Main supplier: NORTHSIDE · 2,086 people · 2015 | 7/8 | SYR4 |
| Arsenic | 8.825 µg/L 88% of the EPA limit 10 µg/L Highest in the city: INGER · 186 people · 2018 | 3/8 | SYR4 |
| Total Haloacetic Acids (HAA5) | 1.68 µg/L 2.8% of the EPA limit 60 µg/L Main supplier: NORTHSIDE · 2,086 people · 2015
Highest in the city: 6.715 µg/L — INGER · 186 people · 2019 | 4/8 | SYR4 |
| Gross Alpha, Excl. Radon And U | 6.34 pCi/L 42% of the EPA limit 15 pCi/L Main supplier: NORTHSIDE · 2,086 people · 2015 | 7/8 | SYR4 |
| TTHM | 5.12 µg/L 6.4% of the EPA limit 80 µg/L Main supplier: NORTHSIDE · 2,086 people · 2019
Highest in the city: 6.08 µg/L — PLANTATION · 105 people · 2019 | 4/8 | SYR4 |
| Chloroform | 5.94 µg/L No EPA limit set Highest in the city: Cass Lake · 691 people · 2019 | 1/8 | SYR4 |
| Bromodichloromethane | 3.56 µg/L No EPA limit set Highest in the city: Cass Lake · 691 people · 2019 | 1/8 | SYR4 |
| Combined Uranium | 0.8433 µg/L 2.8% of the EPA limit 30 µg/L Main supplier: NORTHSIDE · 2,086 people · 2015
Highest in the city: 2.98 µg/L — PLANTATION · 105 people · 2016 | 5/8 | SYR4 |
| Trichloroacetic Acid | 2.08 µg/L No EPA limit set Highest in the city: Cass Lake · 691 people · 2019 | 1/8 | SYR4 |
| Dichloroacetic Acid | 1.985 µg/L No EPA limit set Highest in the city: Cass Lake · 691 people · 2019 | 1/8 | SYR4 |
| Dibromochloromethane | 1.96 µg/L No EPA limit set Highest in the city: Cass Lake · 691 people · 2019 | 1/8 | SYR4 |
| Chromium | 1.59 µg/L 1.6% of the EPA limit 100 µg/L Main supplier: NORTHSIDE · 2,086 people · 2018 | 2/8 | SYR4 |
| Combined Radium (-226 And -228) | 0.6970 pCi/L 14% of the EPA limit 5 pCi/L Main supplier: NORTHSIDE · 2,086 people · 2015
Highest in the city: 1.4 pCi/L — BALL CLUB · 333 people · 2016 | 5/8 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 0.6000 µg/L 10% of the EPA limit 6 µg/L Highest in the city: OAK POINT · 45 people · 2019 | 1/8 | SYR4 |
| Xylenes, Total | 0.5000 µg/L 0% of the EPA limit 10000 µg/L Main supplier: NORTHSIDE · 2,086 people · 2018 | 1/8 | SYR4 |
| Lead | 0.0011 mg/L 7.6% of the EPA limit 0.0150 mg/L Main supplier: NORTHSIDE · 2,086 people · 2025
Highest in the city: 0.0020 mg/L — Cass Lake · 691 people · 2023 | 8/8 | 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 Cass Lake
| Supplier | Population served |
|---|---|
| NORTHSIDE | 2,086 |
| Cass Lake | 691 |
| BALL CLUB | 333 |
| INGER | 186 |
| BENA | 112 |
| PLANTATION | 105 |
| OAK POINT | 45 |
| OLD AGENCY | 30 |
Frequently asked questions about Cass Lake tap water
Is Cass Lake tap water safe to drink?
EPA testing detected 22 contaminants in the water serving Cass Lake. 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 Cass Lake?
8 public water suppliers report drinking-water monitoring for Cass Lake, Minnesota to the EPA. Each is listed above with its population served.
What contaminants are in Cass Lake's water?
The contaminants EPA monitoring detected in Cass Lake include Nitrate, Fluoride, Lead, Copper, Barium. 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.