New Hampshire Well Water
Last reviewed October 29, 2026
Overview
Private wells supply water to many New Hampshire 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
New Hampshire relies heavily on fractured bedrock and glacial aquifers. The documented regional concerns below indicate what is worth testing for — not what any individual well contains.
Documented regional concerns
- Naturally occurring arsenic in parts of the state — odorless and tasteless, so only testing reveals it.
- Radon in water where granitic or uranium-bearing bedrock is present.
- Naturally occurring uranium in some aquifers.
- Iron and manganese causing staining and metallic taste (aesthetic).
- Naturally acidic (low pH) water that can corrode plumbing and leach metals such as lead or copper.
These are documented possibilities, not a reading of your well
Frequently asked questions
What should well owners in New Hampshire test for?
A practical panel for New Hampshire private wells includes Total coliform bacteria, Nitrate (as N), pH, Arsenic, Radon, Uranium, Iron, Manganese, Lead, Copper. Test bacteria and nitrate at least annually and use a state-certified laboratory; confirm local recommendations with your state health department and University of New Hampshire Cooperative Extension.
Are private wells regulated in New Hampshire?
Private wells are generally not covered by the federal Safe Drinking Water Act, though New Hampshire 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.