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Private wells in Maine: labs, drillers and who to call
One place for Maine well owners, buyers and the pros who work with them: the state's private well program, how to find a state-certified lab and a licensed well driller, and every Maine page on this site. Every fact links to its source.
Maine at a glance
- Who's on a well: USGS estimates about 660,000 people in Maine supplied their own household water in 2015, about 50% of the state's population. Most of them use private wells.1
- Who tests: EPA rules for public water systems don't apply to private wells, so testing is up to the owner. CDC says to test at least once a year for total coliform bacteria, nitrates, total dissolved solids and pH, use a state-certified lab, and ask your health department what else to test for where you live.2
- Selling or buying a home: No test required. The seller's disclosure must include the water system type, malfunctions, the date of the most recent water test, and any unsatisfactory test or PFAS detection.3
Who to contact
- State private well information: Maine CDC: Private Well Water.4
- Licensed well drillers and pump installers: Maine CDC: Drinking Water Professionals (well driller and pump installer licensing). Check a contractor's license before you hire.
- State-certified labs: the Maine Department of Health & Human Services certifies labs for drinking water testing. Find a certified drinking water lab (PDF). Many certified labs are city or industry labs that only test their own samples, so call before you send a sample.5
- Local help: CDC says local or state health or environmental departments often test for nitrates and coliform bacteria, should have a list of certified labs, and can help you understand your results.2
- EPA Safe Drinking Water Hotline: (800) 426-4791.2
County pages
- Well water testing in Cumberland County, MEArsenic, uranium and radon testing for Cumberland County private wells, Maine CDC's free help line and testing schedule, the state lab's test kits, and accredited labs, with sources.
- Well water testing in Penobscot County, MEArsenic, uranium and radon testing for Penobscot County private wells, Maine CDC's free help line and testing schedule, the state lab's test kits, and accredited labs, with sources.
Find a pro in Maine
Our directory doesn't cover Maine yet. Use the official driller and lab lookups above.
Guides for Maine well owners
- Buying a home with a well (offer contingencies, which tests to order, and home-sale rules by state)
- Who regulates private wells?
- How often to test a private well
- Best way to test well water
- How to read your well water test results
- Arsenic in well water, nitrate, uranium and radon
- Getting a new well drilled
- Shock chlorinating a well
- For professionals: selling a home with a well (realtors) and homes with a well (home inspectors)
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Dieter, C.A., and others, 2018, Estimated Use of Water in the United States County-Level Data for 2015 (ver. 2.0), U.S. Geological Survey data release (state totals of the county self-supplied domestic population). https://doi.org/10.5066/F7TB15V5 ↩
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CDC, "Guidelines for Testing Well Water" (July 1, 2024). https://www.cdc.gov/drinking-water/safety/guidelines-for-testing-well-water.html ↩↩↩
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33 M.R.S. § 173. https://legislature.maine.gov/statutes/33/title33sec173.html ↩
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U.S. EPA, "Private Drinking Water Well Programs in Your State" (state links; we updated links that had moved). https://www.epa.gov/privatewells/private-drinking-water-well-programs-your-state ↩
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U.S. EPA, "State Certification Programs Certify Laboratories to Conduct Drinking Water Analyses" (August 2025). https://www.epa.gov/system/files/documents/2023-03/state-cert-programs-certify-labs-to-conduct-drinking-water-analyses.pdf ↩