Groundwater in Otter Tail County contains arsenic, iron, lead, and chemicals called PFOA and PFOS that well owners should know about. Several of these contaminants exceed EPA health standards and warrant attention.
These contaminants come from different sources in the local geology and land use. Arsenic occurs naturally in the rock layers beneath the county. Iron is released into groundwater as it moves through the rock. PFOA and PFOS are human-made chemicals that have entered groundwater from industrial or commercial activities and certain firefighting foams used at airports or military sites.
Groundwater in this county is very hard, driven by elevated calcium and magnesium dissolving from the rock as water passes through. The "other rocks" that make up the aquifer here include varied mineral-rich layers that release these hardness minerals into the water over time. Very hard water is the dominant characteristic across most wells in Otter Tail County.
Wells in Otter Tail County commonly contain arsenic, lead, radon, and PFOA and PFOS chemicals at levels that exceed EPA health standards. Arsenic and lead build up in your body over time and can cause serious problems with your nerves, bones, and organs. Radon is a radioactive gas that increases the risk of lung cancer. PFOA and PFOS are chemicals that can affect your liver, immune system, and thyroid.
The very hard water in county wells causes real problems at home. Hard water leaves white scale buildup on faucets, shower heads, and inside pipes. It makes soap work poorly and can leave spots on dishes and glasses. Hard water also shortens the lifespan of water heaters, dishwashers, and washing machines because scale clogs them up over time.
We recommend testing your well water as soon as possible. Every well is different, and your water could have higher or lower levels than what is common in the county. Testing is the only way to know what is actually in your well so you can treat it properly. A comprehensive panel that checks for metals, chemicals, and bacteria runs between two hundred and four hundred dollars. Treatment options like activated carbon filters or ion exchange softeners can address multiple concerns at once.
Not sure if your well is affected? Get certified results in 5–7 days.
Test Your Well Water with Tap Score →| Contaminant | Samples ⓘ | % Above MCL ⓘ | Distribution ⓘ | Confidence ⓘ | Risk ⓘ |
|---|---|---|---|---|---|
| Manganese | 581 | 59% | High | High | |
| Iron | 717 | 51% | High | High | |
| PFOA ⓘ municipal | 33 | 36% | Moderate | High | |
| Nitrate | 469 | 29% | High | High | |
| Arsenic | 285 | 25% | High | High | |
| PFOS ⓘ municipal | 28 | 11% | Moderate | Moderate | |
| PFHxS ⓘ municipal | 19 | 11% | Moderate | Moderate | |
| Sulfate | 623 | 2% | High | Low | |
| Lead | 313 | 1% | High | Low | |
| Nitrite | 368 | 0% | High | Low | |
| Chloride | 929 | 0% | High | Low | |
| Fluoride | 512 | 0% | High | Low | |
| HFPO-DA (GenX) ⓘ municipal | 13 | 0% | Low | Safe | |
| PFNA ⓘ municipal | 15 | 0% | Moderate | Low | |
| Radon | 23 | 0% | Moderate | Low ⓘ | |
| Uranium | 33 | 0% | Moderate | Low | |
| Hardness | 229 | — | High | Low | |
| PFBS ⓘ municipal | 21 | — | Moderate | Low | |
| E. coli | 1* | 0% | Low | Low ⓘ | |
| pH | 529 | — | High | Low | |
| Sodium | 586 | — | High | Low |
MCL = Maximum Contaminant Level (EPA limit for public water; used as benchmark for private wells). Distribution shows % of sampled wells in each concentration band. Methodology.
* Microbial contaminants (E. coli, coliform) reflect only samples from the last 10 years.
Data shows potential risk — a certified test confirms whether your water is affected.
Order a Tap Score Test →Population-level CDC data. Not individual risk prediction.
Loading recent water news…