Water in Maine.
Maine led the country in PFAS regulation after biosolids-spread sludge contaminated dairy farms and household wells across the state. About 40% of Mainers drink from private wells with no testing requirement, raising natural-arsenic exposure concerns.
Maine became the first state to ban biosolids land application after widespread PFAS farm contamination.
How Maine regulates drinking water.
Among the strictest state PFAS frameworks in the country. Maine MCLs for six PFAS compounds at 20 ng/L combined. 2022 statewide biosolids land-application ban.
Maine's water history, in order.
The contamination events, regulatory shifts, and major settlements that define how this state thinks about drinking water today.
- 2018
PFAS contamination identified at Fairfield dairy farms from biosolids fertilizer.
- 2021
Maine sets MCL of 20 ng/L combined for six PFAS compounds.
- 2022
Maine becomes first state to ban biosolids land application.
- 2024
Statewide private-well PFAS testing program expands; PFAS Fund established.
The actual water you drink.
The physical rivers, aquifers, lakes, and reservoirs that feed Maine's public water systems. Source quality is the foundation of tap quality — and where the long-term protection fights happen.
- lakeSebago Lake
Portland Water District — among the best municipal source water in the U.S.
- riverPenobscot River
Bangor area.
- aquiferGlaciofluvial Sand and Gravel Aquifers
Common groundwater source for rural ME.
Source-water mix
~60% surface water, ~40% groundwater (high private well share)
Major cities served
Portland · Lewiston · Bangor · Augusta
Who actually serves the water.
The largest public water systems in Maine by population served. Click your ZIP after to see the full live EWG report for your specific utility.
- Portland Water DistrictPortland200Kserved
- Bangor Water DistrictBangor38Kserved
Where the contamination comes from.
Every state has a different industrial fingerprint. The industries below are the dominant historical and active contamination sources in Maine's drinking water systems.
Statewide biosolids land application (historical) drove the country's most-documented agricultural PFAS contamination. Paper mill legacy chlorinated organics in Penobscot and Androscoggin basins. Brunswick Naval Air Station PFAS plume.
What state data flags most consistently.
Drawn from EPA SDWIS sampling records, EWG state summaries, and regional regulatory action over the past five years. Read the full deep dive on each.
PFAS (Forever Chemicals)
A class of ~15,000 synthetic chemicals that don't break down. Now regulated for the first time.
Arsenic
A naturally occurring carcinogen. Highest in private wells and the rural Southwest.
Lead
A neurotoxic metal that leaches from old pipes and solder. No safe level for children.
Nitrate
Fertilizer and animal waste runoff. Acutely dangerous for infants under 6 months.
Risk isn't evenly distributed.
Maine farmers and rural households on private wells in the Fairfield / Unity / Arundel corridors face the most-documented PFAS exposure.
~40% of Mainers — one of the highest private-well rates in the U.S. — most without testing requirements.
What's coming for Maine's water.
Coastal aquifer salinization affects southern Maine. Increasing intense rainfall events overwhelm small-system treatment. Forest pest die-offs reshape forested watershed hydrology.
Statewide mandate
Maine LD 153 (2021) requires every K-12 school and licensed childcare to test for lead. Results posted publicly on Maine CDC site.
Five questions for your next Consumer Confidence Report.
Your utility is required to send you a Consumer Confidence Report annually. Most are dense and procedural. These are the questions worth following up on for Maine specifically.
- 1
If I'm on a private well, has it been tested for PFAS, arsenic, and uranium?
- 2
Has my school posted recent LD 153 lead testing results?
- 3
Has my farm or land received biosolids application historically (pre-2022 ban)?
Most state regulators allow public records requests for the underlying lab reports behind your CCR — your utility should be able to provide them on request.
What's changed in Maine water law.
Drinking water regulation moves at the state level as much as the federal level. Below are notable recent bills and regulatory actions specific to Maine.
- 2023
LD 1503 — PFAS in consumer products statewide ban (most aggressive in U.S.).
- 2022
LD 1911 — Biosolids land application ban.
- 2021
LD 153 — School Lead Testing mandate.
- 2021
LD 129 — PFAS MCLs set at 20 ng/L combined for six compounds.
For private wells: test first. Then NSF/ANSI 58 reverse osmosis for the combination of PFAS, arsenic, and bacteria.
We don't recommend brands — the NSF/ANSI certification number matters more than the name on the box.
Recent coverage.
This is the state. Your address is the answer.
State-level patterns don't tell you about your specific tap. Run your ZIP for the live EWG contaminant report on your utility — or build a personalized Water File for your household.
Source-water mix, utility counts, lead-service-line estimates, and private-well shares are approximate, drawn from EPA SDWIS public data and state primacy-agency summaries. Contaminant rankings reflect EWG state-level monitoring data and regional regulatory action — they are not exhaustive. Timeline events are publicly documented. See methodology for the full sourcing. Search EPA SDWIS for Maine