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 lead.
Idaho's private well pageLead in Idaho well water, by county
Lead is widespread, over the limit in 15% or more of tested wells, in 1 of the 25 Idaho 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.
These tests sample the groundwater, and lead rarely comes from the ground. In a home it mostly comes from plumbing: old solder, brass fittings and some older pumps. So a county's share can't tell you about your pipes. Test a first-draw sample, water that sat in the pipes overnight, from the tap you drink from.
How Idaho compares with the rest of the country
Across Idaho, about 1 in 9 tested wells had lead over the EPA action level of 15 µg/L (142 of 1,323). Across all tested wells in the US it's under 1 in 50. So lead turns up in Idaho wells about 7 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: It harms children's growing brains. The CDC says no amount in a child's blood is known to be safe.
Lead in tested wells, county by county
Share of each county's tested wells with at least one result over the EPA action level of 15 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 |
|---|---|---|---|
| Shoshone County | 494 | Widespread | |
| Kootenai County | 28 | Worth checking | |
| Bannock County | 16 | Worth checking | |
| Bingham County | 21 | Rare | |
| Butte County | 118 | Rare | |
| Jerome County | 54 | Rare | |
| Minidoka County | 54 | Rare | |
| Gem County | 50 | Rare | |
| Ada County | 44 | Rare | |
| Gooding County | 40 | Rare | |
| Canyon County | 39 | Rare | |
| Owyhee County | 28 | Rare | |
| Elmore County | 25 | Rare | |
| Twin Falls County | 23 | Rare | |
| Jefferson County | 22 | Rare | |
| Lincoln County | 22 | Rare | |
| Cassia County | 19 | Rare | |
| Clark County | 17 | Rare | |
| Bonner County | 14 | Rare | |
| Idaho County | 14 | Rare | |
| Latah County | 14 | Rare | |
| Washington County | 14 | Rare | |
| Custer County | 12 | Rare | |
| Benewah County | 11 | Rare | |
| Fremont County | 10 | Rare |
19 more Idaho counties have 1 to 9 tested wells for lead, too few to rate.
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Where to get your well tested for lead in Idaho
A lab Idaho certifies
Ask for lead 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 lead.
Compare kitsKeep reading about wells in Idaho
- Well water testing in Idaho: how to get tested and what turns up statewide
- Lead 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
- Uranium in Idaho wells, by county
- Manganese in Idaho wells, by county
Questions people ask about lead in Idaho
Is there lead in Idaho well water?
Lead is widespread, over the limit in 15% or more of tested wells, in 1 of the 25 Idaho counties with 10 or more tested wells. Across Idaho, about 1 in 9 tested wells had lead over the EPA action level of 15 µg/L (142 of 1,323). Across all tested wells in the US it's under 1 in 50. So lead turns up in Idaho wells about 7 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 lead 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 lead 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 action level of 15 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.