Free testing, with limits
New Mexico offers free screening at water fairs and some field offices, but it doesn't replace a certified lab test. Check which tests it includes before you count on it for manganese.
New Mexico's private well pageManganese in New Mexico well water, by county
Manganese is widespread, over the limit in 15% or more of tested wells, in 3 of the 15 New Mexico 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 New Mexico compares with the rest of the country
Across New Mexico, about 2 in 10 tested wells had manganese over the EPA health advisory of 0.3 mg/L (114 of 743). Across all tested wells in the US it's about 1 in 7. New Mexico is about average, so the county you live in tells you more than the state does.
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 |
|---|---|---|---|
| Valencia County | 10 | Widespread | |
| San Juan County | 56 | Widespread | |
| Sierra County | 11 | Widespread | |
| Doña Ana County | 150 | Widespread | |
| Bernalillo County | 165 | Worth checking | |
| Lincoln County | 22 | Worth checking | |
| Roosevelt County | 40 | Worth checking | |
| Sandoval County | 28 | Worth checking | |
| Rio Arriba County | 36 | Worth checking | |
| Catron County | 24 | Worth checking | |
| Cibola County | 38 | Worth checking | |
| Santa Fe County | 21 | Rare | |
| Curry County | 51 | Rare | |
| Otero County | 35 | Rare | |
| McKinley County | 13 | Rare |
* Likely overstated. These shares come from a narrow set of wells, so they probably run high for the county as a whole:
- Sierra County: All of these tests come from the US Geological Survey in one small part of the county, so it may not match the rest of the county.
9 more New Mexico 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 New Mexico
A lab New Mexico certifies
Ask for manganese by name. Results from a certified lab count for a home sale or a loan.
Labs certified by New MexicoA 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 New Mexico
- Well water testing in New Mexico: 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 New Mexico wells, by county
- Arsenic in New Mexico wells, by county
- Uranium in New Mexico wells, by county
- Lead in New Mexico wells, by county
Questions people ask about manganese in New Mexico
Is there manganese in New Mexico well water?
Manganese is widespread, over the limit in 15% or more of tested wells, in 3 of the 15 New Mexico counties with 10 or more tested wells. 1 more look high, but those results likely overstate it. Across New Mexico, about 2 in 10 tested wells had manganese over the EPA health advisory of 0.3 mg/L (114 of 743). Across all tested wells in the US it's about 1 in 7. New Mexico is about average, so the county you live in tells you more than the state does.
Where can I get my well tested for manganese in New Mexico?
New Mexico offers free screening at water fairs and some field offices, but it doesn't replace a certified lab test. If that doesn't cover you, use a lab certified by New Mexico for drinking water, or a mail-in kit that includes manganese from a certified lab.
See New Mexico'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: Environment Department.