Tested Water

Nitrate in Nevada well water, by county

Nitrate is widespread, over the limit in 15% or more of tested wells, in 1 of the 12 Nevada 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 Nevada compares with the rest of the country

Across Nevada, about 1 in 16 tested wells had nitrate over the EPA limit of 10 mg/L (52 of 824). Across all tested wells in the US it's about 1 in 12. That's less often than in the country as a whole. Counties still differ, so check yours below.

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%.

CountyWells testedWells over the limitLevel
Washoe County 116
22% 26 of 116
Widespread
Humboldt County 15
13% 2 of 15
Worth checking
Nye County 65
6% 4 of 65
Worth checking
Lyon County 19
5% 1 of 19
Worth checking
White Pine County 24
4% 1 of 24
Rare
Churchill County 147
4% 6 of 147
Rare
Douglas County 275
4% 10 of 275
Rare
Carson City 42
2% 1 of 42
Rare
Clark County 35
0% 0 of 35
Rare
Elko County 35
0% 0 of 35
Rare
Eureka County 11
0% 0 of 11
Rare
Lincoln County 11
0% 0 of 11
Rare

5 more Nevada 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 Nevada

1

Your county health department

Nevada 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.

Nevada's private well page
2

A lab Nevada certifies

Ask for nitrate by name. Results from a certified lab count for a home sale or a loan.

Labs certified by Nevada
3

A mail-in kit

Fill the bottles at your kitchen tap and mail them back. We mark the kits that include nitrate.

Compare kits

Keep reading about wells in Nevada

Questions people ask about nitrate in Nevada

Is there nitrate in Nevada well water?

Nitrate is widespread, over the limit in 15% or more of tested wells, in 1 of the 12 Nevada counties with 10 or more tested wells. Across Nevada, about 1 in 16 tested wells had nitrate over the EPA limit of 10 mg/L (52 of 824). Across all tested wells in the US it's about 1 in 12. 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 nitrate in Nevada?

Use a lab certified by Nevada 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 Nevada'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: Division of Environmental Protection.