Well Water in Knox County: What to Test and Why

High Risk
Testing Strongly Recommended 859 well tests on record
Top Concerns in This County
Nitrate Sulfate Chloride

Why This Happens Here

Groundwater in Knox County contains nitrate, sulfate, chloride, arsenic, fluoride, iron, and manganese at levels that exceed EPA health standards. Several of these contaminants reach concerning concentrations that well owners should address.

The rock beneath Knox County naturally holds and releases these minerals and salts into groundwater. Nitrate can also enter from agricultural fertilizers and septic systems in the area. As water moves slowly through the underground rock layers, it dissolves these compounds and picks them up along the way.

Groundwater in this county is very hard, with elevated calcium and magnesium, alongside very high sodium and sulfate that give the water a distinct mineral character. The local rock formations dissolve readily when exposed to water, releasing these dissolved solids. These mineral and contaminant characteristics are widespread across Knox County wells.

What This Means for You

Wells in Knox County contain arsenic, fluoride, nitrate, and manganese at levels that exceed EPA health standards. Arsenic exposure increases the risk of cancer and can harm organs like the kidneys and heart. Fluoride at elevated levels can damage children's tooth enamel during development. Nitrate is especially dangerous for infants and can interfere with how the body uses oxygen. Manganese can affect the nervous system, particularly in children.

The water in this county is extremely hard with very high sodium and sulfate. Hard water leaves white crusty buildup on faucets and fixtures and makes soap less effective for cleaning. The minerals can give water a bitter or unpleasant taste and a sulfur-like smell. This extreme hardness will shorten the lifespan of water heaters, dishwashers, and other appliances because scale builds up inside them.

Every well is different and yours 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 it can be properly treated. We recommend a comprehensive metals and minerals panel, which runs $200 to $400. Iron removal systems and water softeners can help address these mineral concerns.

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 ⓘ
Nitrate 88 76%
Moderate High
Sulfate 119 67%
High High
Chloride 119 52%
High High
Iron 202 7%
High Moderate
Arsenic 114 5%
High Moderate
Manganese 194 4%
High Moderate
Elevated concentration, not % above limit
Fluoride 780 2%
High Low
Lead 98 0%
Moderate Low
Nitrite 37 0%
Moderate Low
Uranium 16 0%
Moderate Low
Sodium 54 —
Moderate Low
pH 68 —
Moderate Low
Hardness 54 —
Moderate 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.

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Population Health Context

Population-level CDC data. Not individual risk prediction.

5.6%
Cancer Prevalence
(state avg: 6.1%)
3.1%
Kidney Disease Rate
(state avg: 3.3%)

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