Your county health department
Oklahoma 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.
Oklahoma's private well pageManganese in Oklahoma well water, by county
Manganese is widespread, over the limit in 15% or more of tested wells, in 3 of the 33 Oklahoma counties with 10 or more tested wells. 1 more look high, but those results likely overstate it. 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 Oklahoma compares with the rest of the country
Across Oklahoma, about 1 in 21 tested wells had manganese over the EPA health advisory of 0.3 mg/L (53 of 1,130). Across all tested wells in the US it's about 1 in 7. That's less often than in the country as a whole. Counties still differ, so check yours below.
Why it matters: High levels over many years may affect the nervous system, and babies are more sensitive to it. It also leaves black stains.
Manganese dissolves out of rock and soil, especially in water with little oxygen.
Manganese in tested wells, county by county
Share of each county's tested wells with at least one result over the EPA health advisory of 0.3 mg/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 |
|---|---|---|---|
| Canadian County | 22 | Widespread | |
| Kay County | 12 | Widespread | |
| Ottawa County | 18 | Widespread | |
| Seminole County | 25 | Widespread | |
| Pontotoc County | 14 | Worth checking | |
| Pawnee County | 16 | Worth checking | |
| Comanche County | 11 | Worth checking | |
| Pottawatomie County | 70 | Worth checking | |
| Oklahoma County | 174 | Worth checking | |
| Osage County | 43 | Rare | |
| Cleveland County | 103 | Rare | |
| Caddo County | 37 | Rare | |
| Major County | 52 | Rare | |
| Woodward County | 42 | Rare | |
| Murray County | 37 | Rare | |
| Johnston County | 32 | Rare | |
| Beckham County | 25 | Rare | |
| Blaine County | 23 | Rare | |
| Texas County | 23 | Rare | |
| Washita County | 22 | Rare | |
| Logan County | 20 | Rare | |
| Woods County | 18 | Rare | |
| Custer County | 16 | Rare | |
| Garfield County | 16 | Rare | |
| Kingfisher County | 16 | Rare | |
| Lincoln County | 16 | Rare | |
| Stephens County | 15 | Rare | |
| Bryan County | 13 | Rare | |
| Beaver County | 11 | Rare | |
| Delaware County | 11 | Rare | |
| Greer County | 11 | Rare | |
| Marshall County | 11 | Rare | |
| Alfalfa County | 10 | Rare |
* Likely overstated. These shares come from a narrow set of wells, so they probably run high for the county as a whole:
- Canadian County: Almost all of these tests come from Oklahoma's environment department, mostly before 2013 in one small part of the county, so this likely overstates it.
28 more Oklahoma counties have 1 to 9 tested wells for manganese, too few to rate.
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Where to get your well tested for manganese in Oklahoma
A lab Oklahoma certifies
Ask for manganese by name. Results from a certified lab count for a home sale or a loan.
Labs certified by OklahomaA mail-in kit
Fill the bottles at your kitchen tap and mail them back. We mark the kits that include manganese.
Compare kitsKeep reading about wells in Oklahoma
- Well water testing in Oklahoma: how to get tested and what turns up statewide
- Manganese in well water: where it comes from, what it does and how to remove it
- Nitrate in Oklahoma wells, by county
- Arsenic in Oklahoma wells, by county
- Uranium in Oklahoma wells, by county
- Lead in Oklahoma wells, by county
Questions people ask about manganese in Oklahoma
Is there manganese in Oklahoma well water?
Manganese is widespread, over the limit in 15% or more of tested wells, in 3 of the 33 Oklahoma counties with 10 or more tested wells. 1 more look high, but those results likely overstate it. Across Oklahoma, about 1 in 21 tested wells had manganese over the EPA health advisory of 0.3 mg/L (53 of 1,130). Across all tested wells in the US it's about 1 in 7. 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 manganese in Oklahoma?
Use a lab certified by Oklahoma for drinking water, or a mail-in kit that includes manganese from a certified lab. Some county health departments test wells too, so call yours first.
See Oklahoma'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 health advisory of 0.3 mg/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 Environmental Quality.