Free state testing
Idaho sends well owners a free test kit, one per household every 5 years. Check which tests it includes before you count on it for uranium.
Idaho's private well pageUranium in Idaho well water, by county
Uranium is rare in tested Idaho wells: in all 7 counties with enough tests, fewer than 5% of tested wells were over the limit. 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 Idaho compares with the rest of the country
Across Idaho, 2 of 303 tested wells had uranium over the EPA limit of 30 µg/L (2 of 303). Across all tested wells in the US it's about 1 in 22. That's less often than in the country as a whole. Counties still differ, so check yours 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%.
| County | Wells tested | Wells over the limit | Level |
|---|---|---|---|
| Butte County | 91 | Rare | |
| Gem County | 49 | Rare | |
| Minidoka County | 42 | Rare | |
| Jerome County | 28 | Rare | |
| Gooding County | 24 | Rare | |
| Owyhee County | 16 | Rare | |
| Elmore County | 11 | Rare |
13 more Idaho 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 Idaho
A lab Idaho certifies
Ask for uranium by name. Results from a certified lab count for a home sale or a loan.
Labs certified by IdahoA mail-in kit
Fill the bottles at your kitchen tap and mail them back. We mark the kits that include uranium.
Compare kitsKeep reading about wells in Idaho
- Well water testing in Idaho: how to get tested and what turns up statewide
- Uranium in well water: where it comes from, what it does and how to remove it
- Nitrate in Idaho wells, by county
- Arsenic in Idaho wells, by county
- Manganese in Idaho wells, by county
- Lead in Idaho wells, by county
Questions people ask about uranium in Idaho
Is there uranium in Idaho well water?
Uranium is rare in tested Idaho wells: in all 7 counties with enough tests, fewer than 5% of tested wells were over the limit. Across Idaho, 2 of 303 tested wells had uranium over the EPA limit of 30 µg/L (2 of 303). Across all tested wells in the US it's about 1 in 22. That's less often than in the country as a whole. Counties still differ, so check yours below.
Where can I get my well tested for uranium in Idaho?
Idaho sends well owners a free test kit, one per household every 5 years. If that doesn't cover you, use a lab certified by Idaho for drinking water, or a mail-in kit that includes uranium from a certified lab.
See Idaho'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: Department of Health and Welfare.