Your county health department
North Carolina 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.
North Carolina's private well pageNitrate in North Carolina well water, by county
Nitrate has turned up often in 2 of the 13 North Carolina counties with 10 or more tested wells, but those results likely overstate it, because of who tested the wells, when or where. 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 North Carolina compares with the rest of the country
Across North Carolina, about 1 in 10 tested wells had nitrate over the EPA limit of 10 mg/L (47 of 460). Across all tested wells in the US it's about 1 in 12. North Carolina is about average, so the county you live in tells you more than the state does.
Why it matters: It's dangerous for babies under 6 months, because it keeps their blood from carrying enough oxygen.
Nitrate soaks down into groundwater from fertilizer, manure and septic systems.
Nitrate in tested wells, county by county
Share of each county's tested wells with at least one result over the EPA limit of 10 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 |
|---|---|---|---|
| Wake County | 23 | Widespread | |
| Greene County | 70 | Widespread | |
| Onslow County | 15 | Worth checking | |
| Lee County | 26 | Rare | |
| New Hanover County | 49 | Rare | |
| Brunswick County | 40 | Rare | |
| Iredell County | 26 | Rare | |
| Craven County | 22 | Rare | |
| Rockingham County | 19 | Rare | |
| Buncombe County | 17 | Rare | |
| Pender County | 14 | Rare | |
| Randolph County | 13 | Rare | |
| Beaufort 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:
- Wake County: All of these tests come from the US Geological Survey between 2001 and 2007, so this likely overstates it.
- Greene County: All of these tests come from the US Geological Survey, mostly before 2013 in one small part of the county, so this likely overstates it.
43 more North Carolina counties have 1 to 9 tested wells for nitrate, too few to rate.
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Where to get your well tested for nitrate in North Carolina
A lab North Carolina certifies
Ask for nitrate by name. Results from a certified lab count for a home sale or a loan.
Labs certified by North CarolinaA mail-in kit
Fill the bottles at your kitchen tap and mail them back. We mark the kits that include nitrate.
Compare kitsKeep reading about wells in North Carolina
- Well water testing in North Carolina: how to get tested and what turns up statewide
- Nitrate in well water: where it comes from, what it does and how to remove it
- Arsenic in North Carolina wells, by county
- Uranium in North Carolina wells, by county
- Manganese in North Carolina wells, by county
- Lead in North Carolina wells, by county
Questions people ask about nitrate in North Carolina
Is there nitrate in North Carolina well water?
Nitrate has turned up often in 2 of the 13 North Carolina counties with 10 or more tested wells, but those results likely overstate it, because of who tested the wells, when or where. Across North Carolina, about 1 in 10 tested wells had nitrate over the EPA limit of 10 mg/L (47 of 460). Across all tested wells in the US it's about 1 in 12. North Carolina is about average, so the county you live in tells you more than the state does.
Where can I get my well tested for nitrate in North Carolina?
Use a lab certified by North Carolina for drinking water, or a mail-in kit that includes nitrate from a certified lab. Some county health departments test wells too, so call yours first.
See North Carolina'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 10 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 Health and Human Services.