Nitrate in Idaho well water
In Idaho, 8% of 51,233 tested private well samples exceeded the EPA limit for nitrate (10 mg/L).
Nitrate reaches wells from fertilizer, septic systems and manure. Above the limit it can cause methemoglobinemia (blue baby syndrome) in infants under six months, and long-term exposure is associated with some cancers. Shallow and dug wells near farmland or dense septic systems are most at risk.
Check your nitrate number
Type the value from your lab report. It is compared to the EPA limit, the same way the full interpretation does it.
Test your Idaho well for nitrate
Certified lab analysis of your own tap water, bottles and prepaid return shipping included. The Essential well panel covers arsenic, uranium, nitrate, lead, copper, manganese, iron, sodium and bacteria; radon and PFAS are add-ons.
Order the Tap Score well water test kit, from $209Already tested? Upload the report
Affiliate links: the merchant pays us a commission and the price is the same for you. It does not change what the data above says.
Systems that remove nitrate
Some links below are affiliate links. If you buy through one, the merchant pays us a commission at no extra cost to you. It does not change which products we list or what the data says.
Some links below are affiliate links. If you buy through one, the merchant pays us a commission at no extra cost to you. It does not change which products we list or what the data says.
For nitrate
Under-sink reverse osmosis system
under-sink or countertop, about $300
Look for NSF/ANSI 58 certification listing the contaminant you need removed.
For nitrate
Aquasana SmartFlow reverse osmosis
under-sink or countertop, about $225
Certified to NSF/ANSI 58 and 53 to reduce arsenic (96%, pentavalent), fluoride (90%), lead (99%), nitrate, nitrite and PFOA/PFOS at the kitchen tap, with a remineralizer.
Rather have it installed and sized for your well? Book a free in-home water test with a licensed local company.
Where to get a well tested for nitrate in Idaho: certified labs, state programs and prices.
By county, from individual samples
Public monitoring samples against the EPA limit (10 mg/L); counties with at least 30 samples.
| County | Above EPA limit | Samples | Detected | Median | Highest |
|---|---|---|---|---|---|
| Washington | 620 | 72% | 1.61 | 193 mg/L | |
| Lewis | 224 | 96% | 1.82 | 351 mg/L | |
| Fremont | 1,246 | 97% | 4.5 | 189 mg/L | |
| Elmore | 1,839 | 93% | 2.92 | 323 mg/L | |
| Minidoka | 1,305 | 93% | 3.5 | 270 mg/L | |
| Canyon | 4,170 | 89% | 2.88 | 132 mg/L | |
| Cassia | 1,170 | 98% | 3.49 | 70.9 mg/L | |
| Owyhee | 929 | 66% | 0.361 | 487 mg/L | |
| Twin Falls | 2,937 | 98% | 4.9 | 270 mg/L | |
| Bingham | 2,026 | 97% | 1.95 | 107 mg/L | |
| Ada | 4,324 | 90% | 2.5 | 164 mg/L | |
| Caribou | 586 | 93% | 3.3 | 44.3 mg/L | |
| Payette | 860 | 82% | 2.81 | 61 mg/L | |
| Nez Perce | 423 | 84% | 1 | 46.8 mg/L | |
| Gooding | 712 | 99% | 1.88 | 79.2 mg/L |
- Fort Hall CCD, Bingham County45% of 373
- Nezperce CCD, Lewis County39% of 71
- Weiser CCD, Washington County34% of 495
- Ashton CCD, Fremont County29% of 630
- Burley CCD, Cassia County28% of 287
- Wilder CCD, Canyon County27% of 382
- Heyburn CCD, Minidoka County26% of 183
- Aberdeen CCD, Bingham County24% of 42
- Gooding CCD, Gooding County23% of 165
- Grace CCD, Caribou County21% of 112
- Marsing CCD, Owyhee County21% of 141
- Hollister CCD, Twin Falls County20% of 400
- Buhl CCD, Twin Falls County19% of 394
- Rupert CCD, Minidoka County18% of 372
- Twin Falls CCD, Twin Falls County18% of 373
- Mountain Home CCD, Elmore County17% of 1,573
- Declo CCD, Cassia County17% of 209
- Bruneau CCD, Owyhee County17% of 222
- Nampa CCD, Canyon County17% of 1,424
- Fruitland CCD, Payette County16% of 240
Sources
- Individual samples from the USGS Water Quality Portal and state monitoring, summarized per geography. nitrate counts and shares are listed on each county and town page with their sources.
Analysis: Nitrate in private wells, decade by decade, from the same public records.