Well Water in Polk County: What to Test and Why

High Risk
Testing Strongly Recommended 543 well tests on record
Top Concerns in This County
Iron Manganese Arsenic

Why This Happens Here

Groundwater in Polk County contains iron, manganese, arsenic, lead, nitrate, and chloride at levels that exceed EPA health standards. Several of these contaminants reach concerning concentrations that warrant your attention.

The Lower Cretaceous rock layers beneath this county naturally release iron and manganese as water moves through them over time. Arsenic also occurs naturally in these same rock layers. Nitrate and chloride can come from both natural sources in the rock and from human activities like farming and road salt use.

Groundwater in this county is very hard, driven by elevated calcium and magnesium from the rock below, and also contains very high iron and moderate sodium. As water percolates through the deep sand and rock layers, it dissolves these minerals slowly and steadily. These characteristics show up across most wells in the county.

What This Means for You

Polk County wells commonly exceed EPA health standards for arsenic, chloride, lead, nitrate, and manganese. Arsenic is toxic and builds up in your body over time, raising the risk of cancer and organ damage. Lead harms children's brain development and learning, and damages kidneys and nerves in adults. Nitrate is especially dangerous for infants and can cause serious blood problems. Manganese affects the nervous system and brain development in children.

The county's water is extremely hard, which causes real problems at home. You will see rust-colored stains on sinks, toilets, and laundry from the high iron content. Scale builds up inside water heaters, pipes, and dishwashers, shortening their lifespan. Soap won't lather well, and your dishes may spot after washing. The water may taste metallic or slightly salty.

Your well is different from others in the county, so testing is the only way to know what you are actually dealing with. We recommend a comprehensive metals and minerals panel to check for all these contaminants, which typically costs between two and four hundred dollars. Once you know your results, treatment options like reverse osmosis systems or iron and arsenic filters can address your specific problems.

Not sure if your well is affected? Get certified results in 5–7 days.

Test Your Well Water with Tap Score →

Contaminant Detection Data

Contaminant Samples % Above MCL Distribution Confidence Risk
Iron 118 58%
High High
Manganese 117 58%
High High
Arsenic 29 48%
Moderate High
Nitrate 474 20%
High High
Lead 60 5%
Moderate Moderate
Chloride 131 4%
High Moderate
Elevated concentration, not % above limit
Sulfate 121 3%
High Moderate
Elevated concentration, not % above limit
HFPO-DA (GenX) ⓘ municipal 6 0%
Low Safe
PFOA ⓘ municipal 8 0%
Low Low
PFOS ⓘ municipal 8 0%
Low Low
Fluoride 62 0%
Moderate Low
Nitrite 447 0%
High Low
PFHxS ⓘ municipal 5 0%
Low Safe
PFNA ⓘ municipal 6 0%
Low Safe
Sodium 117
High Low
Hardness 88
Moderate Low
PFBS ⓘ municipal 5
Low Safe
pH 486
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 Health Context

Population-level CDC data. Not individual risk prediction.

7.7%
Cancer Prevalence
(state avg: 7.0%)
3.2%
Kidney Disease Rate
(state avg: 2.9%)
5.7%
Heart Disease Rate
(state avg: 6.6%)

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