Groundwater in Iosco County contains iron, arsenic, chloride, and manganese that well owners should be aware of. Several of these contaminants exceed EPA health standards, making them a concern that warrants attention.
These contaminants come from the Marshall aquifer rock beneath the county. As groundwater moves slowly through this rock formation, it naturally dissolves iron, arsenic, and manganese from the minerals present. Chloride appears partly from ancient salt deposits trapped in the rock and partly from road salt that seeps down through the soil during winter months.
Groundwater in this county is very hard, driven by elevated calcium and magnesium from the limestone and mineral-rich rock below. The water also carries moderate iron and high sodium, which concentrate as water sits in contact with the bedrock for long periods. These characteristics are widespread across wells throughout the county.
Wells in Iosco County commonly contain arsenic, chloride, iron, manganese, and sulfate at levels that exceed EPA health standards. Arsenic is a serious concern because long-term exposure can increase the risk of cancer and damage your kidneys and nervous system. Manganese at elevated levels can harm your brain and affect how your body processes other metals. Chloride at high levels is a concern for people with certain health conditions. Iron itself does not pose a direct health risk at the levels found here, but it indicates other minerals are present in your water.
The high iron and mineral content in county wells causes visible staining and buildup. Orange or reddish-brown stains appear on sinks, toilets, and laundry. The very hard water in this county can shorten the lifespan of water heaters and dishwashers. You may notice a metallic or salty taste, and white crusty scale builds up on faucets and inside pipes.
We recommend testing your well water to find out what you are actually drinking, since every well is different and yours may have higher or lower levels than what is common in the county. A comprehensive metals and minerals panel typically costs $200 to $400 and will tell you exactly what needs treatment. Testing is the only way to know what is in your water so you can choose the right treatment, such as a reverse osmosis system or whole-house water softener.
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 ⓘ |
|---|---|---|---|---|---|
| Iron | 14 | 36% | Low | High | |
| Arsenic | 14 | 14% | Low | Moderate | |
| Chloride | 51 | 12% | Moderate | Moderate | |
| Manganese | 14 | 7% | Low | Moderate | |
| Sulfate | 54 | 2% | Moderate | Low | |
| Fluoride | 14 | 0% | Low | Low | |
| HFPO-DA (GenX) ⓘ municipal | 4 | 0% | Low | Safe ⓘ | |
| Lead | 35 | 0% | Moderate | Low | |
| Nitrite | 47 | 0% | Moderate | Low | |
| PFHxS ⓘ municipal | 4 | 0% | Low | Safe ⓘ | |
| PFNA ⓘ municipal | 4 | 0% | Low | Safe ⓘ | |
| PFOA ⓘ municipal | 5 | 0% | Low | Safe ⓘ | |
| PFOS ⓘ municipal | 4 | 0% | Low | Safe ⓘ | |
| Uranium | 6 | 0% | Low | Low ⓘ | |
| Nitrate | 47 | 0% | Moderate | Low | |
| Sodium | 14 | — | Low | Low | |
| pH | 53 | — | Moderate | Low | |
| PFBS ⓘ municipal | 4 | — | Low | Safe ⓘ | |
| Hardness | 14 | — | Low | 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…