Tested Water

Uranium in Maine well water, by county

Uranium is widespread, over the limit in 15% or more of tested wells, in 3 of the 7 Maine counties with 10 or more tested wells. A county's share tells you how likely a problem is nearby. Only a test of your own well tells you what's in it.

How Maine compares with the rest of the country

Across Maine, about 1 in 8 tested wells had uranium over the EPA limit of 30 µg/L (19 of 150). Across all tested wells in the US it's about 1 in 22. So uranium turns up in Maine wells about 3 times as often as in the country as a whole, and a test is worth adding even if your county isn't on the list below.

Why it matters: Drinking it for years can harm your kidneys and raises the risk of cancer.

Uranium comes out of the rock and sediment the wells draw from.

Uranium in tested wells, county by county

Share of each county's tested wells with at least one result over the EPA limit of 30 µg/L. Counties need 10 or more tested wells to be listed. Widespread means 15% or more, worth checking 5 to 15%, rare under 5%.

CountyWells testedWells over the limitLevel
Hancock County 15
33% 5 of 15
Widespread
Cumberland County 22
23% 5 of 22
Widespread
Androscoggin County 10
20% 2 of 10
Widespread
Kennebec County 43
12% 5 of 43
Worth checking
Knox County 12
8% 1 of 12
Worth checking
York County 13
0% 0 of 13
Rare
Somerset County 10
0% 0 of 10
Rare

6 more Maine counties have 1 to 9 tested wells for uranium, too few to rate.

Download this table (CSV) · Free to reuse under CC BY 4.0

Where to get your well tested for uranium in Maine

1

Your county health department

Maine doesn't run a statewide free testing program that we know of. Some county health departments test wells or sell kits, so call yours first.

Maine's private well page
2

A lab Maine certifies

Ask for uranium by name. Results from a certified lab count for a home sale or a loan.

Labs certified by Maine
3

A mail-in kit

Fill the bottles at your kitchen tap and mail them back. We mark the kits that include uranium.

Compare kits

Keep reading about wells in Maine

Questions people ask about uranium in Maine

Is there uranium in Maine well water?

Uranium is widespread, over the limit in 15% or more of tested wells, in 3 of the 7 Maine counties with 10 or more tested wells. Across Maine, about 1 in 8 tested wells had uranium over the EPA limit of 30 µg/L (19 of 150). Across all tested wells in the US it's about 1 in 22. So uranium turns up in Maine wells about 3 times as often as in the country as a whole, and a test is worth adding even if your county isn't on the list below.

Where can I get my well tested for uranium in Maine?

Use a lab certified by Maine for drinking water, or a mail-in kit that includes uranium from a certified lab. Some county health departments test wells too, so call yours first.

See Maine's list of certified labs, or compare mail-in kits.

Where these numbers come from

  • Lab tests: Water Quality Portal (USGS and EPA), well samples since 2000. A well counts as over if any of its tests was over the EPA limit of 30 µg/L. Wells tested for studies and monitoring, not a random sample of homes.
  • Likely overstated: our own check of who tested the wells, when and where. How we check.
  • State programs and links: Maine CDC (Department of Health and Human Services), Drinking Water Program.