Rural Home CompassMaine homeowner guide · Private well water
When should you test a private well in Maine?
Maine separates the initial-use test from two routine clocks. Its official schedule pairs annual microbial and nitrate/nitrite testing with a broader chemical and radiological review every three to five years. Well work, buying a home, expecting a baby, a dry well, treatment changes, or a credible PFAS source can change the next test.
This plan connects Maine’s official New Well Test and statutory uniform-recommendation framework to annual and three-to-five-year groups, bedrock-related arsenic, uranium, and radon concerns, selective PFAS testing, a separate five-year landlord arsenic-testing duty, accredited laboratory scope, and a well database that includes both mapped and unlocated records.
Four different decisions
Start with why you are testing.
New well
Run Maine’s New Well Test before initial household use.
Maine HETL recommends its New Well Test before initial use. The package measures coliform and E. coli counts, nitrate, nitrite, fluoride, chloride, pH, arsenic, calcium, copper, hardness, iron, magnesium, manganese, and uranium; this is a state recommendation for a residential private well, not a statement that every homeowner is under a statewide testing mandate.
- Order the kit before the planned use date and confirm the current bottles, collection sequence, delivery window, and laboratory scope.
- Keep the complete result with the driller’s completion report, yield information, treatment records, and any local permit documents.
Official guidancePrivate Well WaterTitle 22 §2660-T: Uniform testing recommendationMaine HETL New Well Test
Buying a home
Pair current laboratory evidence with the construction record.
Maine CDC lists buying a new home as a reason to test. The Geological Survey record can describe construction and yield, but mapped locations vary in accuracy and the database also contains unlocated records; neither a well log nor an old result establishes current water quality.
- Search the map and the table by town, address, driller, and date, then ask the seller and municipality for records the database does not resolve.
- Use an accredited laboratory to establish the annual group and any overdue three-to-five-year group before relying on the water for the intended household.
Official guidancePrivate Well WaterLaboratory Accreditation and current listingsMaine Water Well Database and coverage notes
Routine care
Keep an annual date and a three-to-five-year date.
Maine CDC recommends annual testing for coliform bacteria, E. coli, nitrate, and nitrite. Every three to five years it recommends arsenic, chloride, copper, fluoride, hardness, iron, lead, magnesium, manganese, pH, radon, sodium, and uranium; a comprehensive baseline is recommended if the well has never been tested.
- Track the annual four-item group separately from the broader chemical and radiological group so an overdue test is visible.
- Confirm that the selected laboratory is accredited for every requested analyte, including a separate radon scope when needed.
Official guidancePrivate Well WaterTitle 22 §2660-T: Uniform testing recommendationLaboratory Accreditation and current listings
Flood or repair
Treat flooding or opened-well work as a new event.
Maine CDC recommends new testing after any well work, after a dry well returns, and after treatment installation or replacement. For a flooded well, current EPA guidance says not to drink or wash with the water, to obtain qualified inspection and disinfection help, and to sample and test before returning to normal use.
- Use an alternate safe water source and avoid flooded electrical equipment while the well is inspected, cleaned, and disinfected.
- Ask Maine CDC or the laboratory which microbial and site-specific chemical tests fit the event and when the post-work sample should be collected.
Official guidancePrivate Well WaterWhat to Do With Your Private Well After a Flood
New wells and regulated work
Start with the state-recommended panel.
Maine HETL recommends this specific package before initial use of a new residential private well. It is a state recommendation, not a universal homeowner testing mandate, and it is separate from the routine annual and three-to-five-year schedule.
- Coliform bacteria count
- E. coli count
- Nitrate
- Nitrite
- Fluoride
- Chloride
- pH
- Arsenic
- Calcium
- Copper
- Hardness
- Iron
- Magnesium
- Manganese
- Uranium
The responsible professional and certified laboratory determine the accepted sample and report. Do not assume a retail package satisfies a regulatory purpose.
Official basis for the new-well panelPrivate Well WaterTitle 22 §2660-T: Uniform testing recommendationMaine HETL New Well Test
Existing wells
Maine has a state-specific recurring schedule.
This state-recommended package combines microbial indicators, nitrogen compounds, minerals, metals, pH, and uranium; confirm the current kit before ordering.
Official guidanceMaine HETL New Well Test
This is Maine CDC’s recurring private-well baseline, not evidence that unchanged-looking water remains safe without testing.
Official guidancePrivate Well WaterLaboratory Accreditation and current listings
Maine’s broader group includes both naturally occurring and plumbing-related concerns; prior results and credible local evidence can justify a different scope.
Official guidancePrivate Well WaterTitle 22 §2660-T: Uniform testing recommendation
The calendar is not the whole answer
When should the panel change?
Expecting a baby or preparing well water for an infant
Maine CDC names an expected baby as a reason to test now rather than waiting for the next routine date; discuss nitrate, arsenic, and the complete household baseline with the laboratory or Toxicology Team.
Official guidancePrivate Well WaterWell Water Information Request and test-kit assistance
A private well supplies a residential rental building
This is a separate legal duty, not the ordinary owner-occupied schedule: Maine law requires the landlord to test the well for arsenic every five years through a certified or accredited laboratory and provide the result to current and new tenants on the statutory timeline.
Official guidanceTitle 22 §2660-Y: Landlord arsenic testing
A change in smell, taste, or color, or a well that ran dry and returned
Test after the change and let the laboratory and Maine CDC select analytes from the symptom and site context; appearance does not identify the contaminant.
Official guidancePrivate Well Water
Known PFAS source, agency investigation, or notice near the property
Do not add PFAS to every Maine well panel automatically. Maine CDC says PFAS testing is usually used when contamination is plausible and recommends discussing the decision with its toxicologists; only a limited set of laboratories performs the work.
Official guidancePFAS and Well Water
Fuel storage, solvent use, pesticide handling, agricultural fields, or another credible source near the well
Ask Maine CDC, DEP, and an appropriately accredited laboratory whether a targeted VOC, pesticide, or other organic-chemical analysis fits the source rather than ordering an unnamed broad screen.
Official guidanceHydrogeology and WellsEnvironmental Organics and Metals
Treatment installation, replacement parts, well work, flooding, or disinfection
Use event-specific sampling timing and do not substitute an older routine report for a post-work or post-exposure result.
Official guidancePrivate Well WaterWhat to Do With Your Private Well After a Flood
Laboratory and sampling
Confirm the route before collecting water.
Use a Maine-accredited laboratory and confirm accreditation for each analyte; a laboratory’s approval for one test does not establish scope for arsenic, radon, PFAS, or every other requested item.
Official guidanceLaboratory Accreditation and current listings
Contact the laboratory before sampling for its containers, preparation, collection point, chain-of-custody form, preservation, and holding time. Maine HETL says its samples must arrive within 30 hours and should not be collected before weekends or holidays.
Official guidancePrivate-well sampling and HETL submission
For radon or PFAS, use the specific accredited-laboratory listing and collection instructions for that analyte rather than assuming an ordinary chemistry bottle is suitable.
Official guidanceLaboratory Accreditation and current listingsPFAS and Well Water
Official records
Start with the official well-record system.
Maine Geological Survey for submitted well-construction records, with the well driller, seller, and municipality holding additional property documents.
Maine has required well-drilling companies to report new wells since 1987. The map contains only geographically located records and location accuracy varies; use the table search for all reported records, including unlocated records, and do not treat an empty result as proof that no well exists.
Open the official well-record entry point ↗Records and lookup guidanceMaine Water Well Database and coverage notesTitle 12 §550-B: Water well information
- Well number or well card and driller completion report
- Depth, casing, bedrock, yield, and drill date
- Current and prior laboratory reports
- Treatment, repair, disinfection, and local permit records
Turn the schedule into questions
Build a starting water-test panel.
The recommender combines your current issue, purchase status, flood or repair history, nearby agriculture, vulnerable occupants, and ZIP-based Maine context. It does not replace the responsible professional or laboratory.
Open the Well Water Test Recommender →Official sources
These sources were reviewed for this page on 2026-09-13. A build date does not refresh that review.
- Maine Center for Disease Control and Prevention: Private Well WaterReviewed 2026-09-13
- Maine Legislature: Title 22 §2660-T: Uniform testing recommendationReviewed 2026-09-13
- Maine Health and Environmental Testing Laboratory: Maine HETL New Well TestReviewed 2026-09-13 · Recheck every 90 days
- Maine Center for Disease Control and Prevention: Laboratory Accreditation and current listingsReviewed 2026-09-13 · Recheck every 90 days
- Maine Health and Environmental Testing Laboratory: Private-well sampling and HETL submissionReviewed 2026-09-13 · Recheck every 90 days
- Maine Center for Disease Control and Prevention: Well Water Information Request and test-kit assistanceReviewed 2026-09-13 · Recheck every 30 days
- Maine Center for Disease Control and Prevention: PFAS and Well WaterReviewed 2026-09-13 · Recheck every 90 days
- Maine Center for Disease Control and Prevention: Hydrogeology and WellsReviewed 2026-09-13
- Maine Health and Environmental Testing Laboratory: Environmental Organics and MetalsReviewed 2026-09-13
- Maine Geological Survey: Maine Water Well Database and coverage notesReviewed 2026-09-13 · Recheck every 90 days
- Maine Legislature: Title 12 §550-B: Water well informationReviewed 2026-09-13
- Maine Legislature: Title 22 §2660-Y: Landlord arsenic testingReviewed 2026-09-13
- U.S. Environmental Protection Agency: What to Do With Your Private Well After a FloodReviewed 2026-09-13 · Official source updated 2026-06-18