Well water in Lincoln County, Idaho
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Testing strongly recommended
tested well samples in Lincoln County exceeded the EPA limit for total coliform (0 MPN/100mL), based on public data from USGS Water Quality Portal and Idaho statewide ground water quality monitoring (IDWR EDMS).
3,047 test results across 15 contaminants from at least 100 wells, 1929 to 2024; nitrate has the most at 554. Data refreshed September 15, 2026.
Compiled by Nick at Well Water Nerd from public records. How these pages are built
An estimated 3,105 people in Lincoln County get their drinking water from a private well, per USGS 2015 county water use. That is about 59% of residents.
Separately, the USGS national arsenic model estimates that 3% of the 3,105 people on private wells in Lincoln County draw water above 10 ug/L (the model's range is 2% to 4%), from geology and well depth rather than local tests.
What individual samples found
Each row summarizes every public sample for that contaminant inside Lincoln County. Above limit means above the EPA maximum contaminant level; where EPA has no enforceable limit, the row shows a health guideline or nuisance level instead.
| Contaminant | Above limit | Samples | Detected | Median | Highest | Limit |
|---|---|---|---|---|---|---|
| Total coliform 2017 | 55 | 67% | 3 | 2,420 | 0 MPN/100mL EPA limit | |
| Nitrate 1929 to 2024 | 554 | 99% | 1.5 | 35.7 | 10 mg/L EPA limit | |
| Lead 1981 to 2017 | 168 | 30% | 0 | 30 | 15 ug/L EPA limit | |
| Fluoride 1953 to 2024 | 297 | 98% | 0.34 | 1 | 4 mg/L EPA limit | |
| Arsenic 1989 to 2024 | 286 | 85% | 2 | 4 | 10 ug/L EPA limit | |
| Copper 1981 to 2020 | 201 | 49% | 0 | 0.026 | 1.3 mg/L EPA limit | |
| Nitrite 1991 to 2011 | 68 | 3% | 0 | 0.003 | 1 mg/L EPA limit | |
| E. coli 1991 to 2008 | 64 | 0% | 0 | 0 | 0 MPN/100mL EPA limit | |
| Uranium 1956 to 2024 | 53 | 100% | 2.29 | 13 | 30 ug/L EPA limit | |
| Radium (226 + 228) 1989 to 1993 | 32 | 47% | 0 | 0.11 | 5 pCi/L EPA limit | |
| Chloride 1929 to 2024 | no limit | 332 | 100% | 7.42 | 82.3 | 250 mg/L nuisance level |
| Sodium 1947 to 2024 | no limit | 312 | 100% | 15 | 193 | 20 mg/L health guideline |
| Iron 1953 to 2024 | no limit | 301 | 28% | 0 | 1,600 | 300 ug/L nuisance level |
| Manganese 1953 to 2024 | no limit | 293 | 24% | 0 | 19.2 | 300 ug/L health guideline |
| Radon 1989 to 1995 | no limit | 31 | 100% | 56 | 240 | 2,000 pCi/L health guideline |
Over time
Share of samples above the limit by period. A cell needs ten samples to show; a comparison needs twenty in each period. Later periods sample fewer wells, and often the ones already known to have a problem.
| Contaminant | before 2000 | 2000s | 2010s | 2020s |
|---|---|---|---|---|
| Nitrate | 1%265 samples | 2%188 samples | 2%89 samples | 0%12 samples |
| Fluoride | 0%139 samples | 0%106 samples | 0%40 samples | 0%12 samples |
| Arsenic | 0%132 samples | 0%102 samples | 0%40 samples | 0%12 samples |
| Copper | 0%125 samples | 0%35 samples | 0%40 samples | n/a |
| Lead | <1%135 samples | 0%25 samples | n/a | n/a |
| Nitrite | 0%37 samples | 0%29 samples | n/a | n/a |
Nitrate, fluoride, arsenic, copper, lead, nitrite have held within a few points between the two most recent periods with enough samples.
Closer than the county
See the sampled wells near your address
The same records, drawn around one point: which wells within a few miles were sampled and what they found, how deep the wells next to you were drilled, and any leaking tank or cleanup site within a mile.
Check my addressWhat this means
The contaminants most often above their limit here are total coliform (67% of 55 samples), nitrate (1% of 554 samples), and lead (<1% of 168 samples). A well next door can differ sharply from yours because bedrock fractures, well depth and plumbing all matter, so these rates describe the area, not your tap.
Chloride is widespread in local groundwater. It is mainly a staining and taste problem, but high manganese also carries a health advisory for infants.
What to test for in Lincoln County
- 1Total coliform67% of 55 local samples were above the limit.
- 2Nitrate1% of 554 local samples were above the limit.
- 3Lead<1% of 168 local samples were above the limit.
- 4Coliform bacteriaRecommended for every private well, every year.
- 5RadonMedian local reading is 56 pCi/L.
- 6ChlorideDetected in 100% of local samples.
- 7FluorideDetected in 98% of local samples.
Test your Lincoln County well for total coliform, nitrate and lead
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
Just want bacteria checked first? Tap Score coliform and E. coli test, $99. Coliform and E. coli are the tests every well needs every year.
Want a quick look before paying for a lab? Home well water test strips on Amazon check hardness, iron, pH and nitrate in minutes. They are a screen, not a result: arsenic, bacteria, uranium and PFAS need a certified lab.
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. As an Amazon Associate we earn from qualifying purchases.
Where to get a well tested in Idaho: certified labs, state programs and prices.
Already have results back? Get your lab report read against the Lincoln County numbers, $29. Every line explained, ranked by what matters, with the fix for each.
The rock under Lincoln County
Snake River Plain basaltic-rock aquifers
Igneous and metamorphic-rock. Granite and similar crystalline rock hold water only in fractures. Wells are deep and yields modest, and the rock itself is the source of arsenic, radon and uranium, which is why those three head the test list in bedrock country.
Classification from the USGS Principal Aquifers of the United States (national map, 2003 edition, GIS release 2015), read at the county centroid. A single well can sit in a different unit, especially near a boundary.
Official help in Idaho
Two places to start that are not selling anything: the state program that answers private well questions, and its list of labs certified to run drinking water tests. A certified lab is the difference between a result you can act on and a number.
- Wells, Idaho DEQ
- Drinking Water Testing and Certification, Idaho Department of Health and Welfare
Treatment that fits the local profile
Total coliform
Inspect and repair the well cap and casing, then shock chlorinate and retest; UV disinfection whole-house; Chlorination system
Nitrate
Point-of-use reverse osmosis; Anion exchange; Distillation
Lead
Point-of-use reverse osmosis; Certified lead-removal carbon filter; Neutralizing filter to raise pH and stop leaching
Systems we would look at first
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 total coliform
Aquasana Rhino Well Water with UV
whole-house, at the point of entry, about $2,871
Whole-house system built for wells: sediment pre-filter, KDF and carbon, and a UV lamp rated to kill 99.99% of bacteria and viruses. It does not remove arsenic, nitrate, uranium or radon.
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.
For lead
Aquasana Claryum 3-Stage under-sink filter
under-sink or countertop, about $175
Certified to NSF/ANSI 53 to reduce 99% of lead and 99.7% of PFOA and PFOS at the tap. Not a fix for arsenic, nitrate or bacteria.
For lead
Acid neutralizing filter
whole-house, at the point of entry, about $1,200
Raises pH so plumbing stops leaching lead and copper.
Free, no obligation
Get on the list for a free in-home water test in Lincoln County
No water treatment company serves Lincoln County through Well Water Nerd yet. We are signing licensed companies on county by county: they test at your tap for free, walk you through the numbers, and quote treatment only if something needs fixing. Leave your details and you are first in line. Nothing is shared until a company joins for Lincoln County, and you get an email naming it first.
Common questions
Is there arsenic in well water in Lincoln County?
Arsenic was detected in 85% of 286 public well samples in Lincoln County, and 0% were above the EPA limit of 10 ug/L. Arsenic has no taste or smell; a lab test is the only way to know your level.
How high is radon in well water in Lincoln County?
The median radon level across 31 public samples in Lincoln County was 56 pCi/L, with a high of 240 pCi/L. New Hampshire recommends treatment above 2,000 pCi/L.
How often should I test a private well in Lincoln County?
Test for bacteria and nitrate every year. Test once for arsenic, uranium, radon, fluoride, manganese and PFAS, then again every three to five years or after any change in taste, color, or plumbing.
Counties near Lincoln County
Closest first. Groundwater does not stop at a line on a map, so the next county over is a fair second opinion.
Want the numbers themselves? Download the Idaho dataset as CSV, every county and town, with the sources named.
Sources
- USGS Water Quality Portal: 1,927 samples in Lincoln County. Data from the Water Quality Portal, a service of USGS, EPA and USDA; groundwater samples collected by USGS and cooperators. Retrieved September 3, 2026.
- Idaho statewide ground water quality monitoring (IDWR EDMS): 1,120 samples in Lincoln County. Ground water quality results from the Idaho Department of Water Resources statewide monitoring program and partner agencies (ISDA, IDEQ, INL), EDMS bulk download. Retrieved September 9, 2026.
- USGS national arsenic model (Ayotte 2017): estimated share of 3,105 people on private wells in Lincoln County above 10 ug/L of arsenic, from geology, well depth and land use. County estimates of domestic well users with arsenic above 10 ug/L from the USGS national logistic regression model (Ayotte, Medalie and Qi, 2017), with private well population from the USGS 2015 county water-use compilation (Dieter and others, 2018). Retrieved September 15, 2026.
Non-detects count as samples and are treated as zero when computing medians. Exactly at the limit counts as not above it. A sample belongs to the town containing the well's reported coordinates.