Skip to content
KnowYourWellWater

Tennessee Well Water

Last reviewed October 29, 2026

Overview

Private wells supply water to many Tennessee households. Because they are generally not regulated like public systems under the federal Safe Drinking Water Act, testing and wellhead protection are the owner’s responsibility.

Hydrogeology & what it means

Tennessee uses karst (limestone) aquifers in the central basin and Coastal Plain/bedrock aquifers elsewhere. The documented regional concerns below indicate what is worth testing for — not what any individual well contains.

Documented regional concerns

  • Rapid surface-water influence, turbidity and bacteria in karst (limestone) terrain.
  • Hard water from carbonate (limestone/dolomite) aquifers.
  • Radon in water where granitic or uranium-bearing bedrock is present.
  • Iron and manganese causing staining and metallic taste (aesthetic).

These are documented possibilities, not a reading of your well

Regional geology tells you what to test for, not what your specific well contains. Only your own lab results can tell you that.

Frequently asked questions

What should well owners in Tennessee test for?

A practical panel for Tennessee private wells includes Total coliform bacteria, Nitrate (as N), pH, Turbidity, Total hardness, Radon, Iron, Manganese. Test bacteria and nitrate at least annually and use a state-certified laboratory; confirm local recommendations with your state health department and University of Tennessee Cooperative Extension.

Are private wells regulated in Tennessee?

Private wells are generally not covered by the federal Safe Drinking Water Act, though Tennessee or local rules may apply to construction, permitting, or testing. Public-system limits such as EPA MCLs are useful reference points, not automatic legal limits for your well.