Your county health department
Arizona 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.
Arizona's private well pageUranium in Arizona well water, by county
Uranium is widespread, over the limit in 15% or more of tested wells, in 1 of the 7 Arizona 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 Arizona compares with the rest of the country
Across Arizona, about 1 in 10 tested wells had uranium over the EPA limit of 30 µg/L (28 of 280). Across all tested wells in the US it's about 1 in 22. So uranium turns up in Arizona wells about twice 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%.
| County | Wells tested | Wells over the limit | Level |
|---|---|---|---|
| Maricopa County | 96 | Widespread | |
| Mohave County | 17 | Worth checking | |
| Pima County | 27 | Worth checking | |
| Cochise County | 18 | Worth checking | |
| Yavapai County | 49 | Rare | |
| Coconino County | 26 | Rare | |
| Navajo County | 20 | Rare |
7 more Arizona 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 Arizona
A lab Arizona certifies
Ask for uranium by name. Results from a certified lab count for a home sale or a loan.
Labs certified by ArizonaA 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 Arizona
- Well water testing in Arizona: 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 Arizona wells, by county
- Arsenic in Arizona wells, by county
- Manganese in Arizona wells, by county
- Lead in Arizona wells, by county
- Radon in Arizona wells, by county
Questions people ask about uranium in Arizona
Is there uranium in Arizona well water?
Uranium is widespread, over the limit in 15% or more of tested wells, in 1 of the 7 Arizona counties with 10 or more tested wells. Across Arizona, about 1 in 10 tested wells had uranium over the EPA limit of 30 µg/L (28 of 280). Across all tested wells in the US it's about 1 in 22. So uranium turns up in Arizona wells about twice 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 Arizona?
Use a lab certified by Arizona 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 Arizona'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 Services.