Well water in Stevens County, Washington
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Testing strongly recommended
tested well samples in Stevens County exceeded the EPA limit for uranium (30 ug/L), based on public data from USGS Water Quality Portal.
13,392 test results across 12 contaminants from at least 274 wells, 1958 to 2025; radium (226 + 228) has the most at 1,884. Data refreshed September 15, 2026.
Compiled by Nick at Well Water Nerd from public records. How these pages are built
An estimated 21,243 people in Stevens County get their drinking water from a private well, per USGS 2015 county water use. That is about 49% of residents.
Separately, the USGS national arsenic model estimates that 2% of the 21,243 people on private wells in Stevens County draw water above 10 ug/L (the model's range is 1% to 3%), from geology and well depth rather than local tests.
What individual samples found
Each row summarizes every public sample for that contaminant inside Stevens 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 |
|---|---|---|---|---|---|---|
| Uranium 1980 to 2025 | 751 | 100% | 39.6 | 123,000 | 30 ug/L EPA limit | |
| Radium (226 + 228) 1979 to 2025 | 1,884 | 99% | 0.8 | 1,060 | 5 pCi/L EPA limit | |
| Arsenic 1967 to 2015 | 623 | 92% | 3 | 99.4 | 10 ug/L EPA limit | |
| Lead 1967 to 2025 | 1,141 | 94% | 0.9 | 770 | 15 ug/L EPA limit | |
| Fluoride 1958 to 2015 | 341 | 97% | 0.3 | 100 | 4 mg/L EPA limit | |
| Nitrate 1958 to 2018 | 942 | 89% | 0.756 | 716 | 10 mg/L EPA limit | |
| Copper 1967 to 2025 | 1,491 | 95% | 0.003 | 8.08 | 1.3 mg/L EPA limit | |
| Iron 1958 to 2025 | no limit | 1,826 | 96% | 100 | 2,180,000 | 300 ug/L nuisance level |
| Manganese 1967 to 2025 | no limit | 1,757 | 97% | 250 | 1,430,000 | 300 ug/L health guideline |
| Sodium 1958 to 2025 | no limit | 1,238 | 100% | 23 | 500 | 20 mg/L health guideline |
| Chloride 1958 to 2025 | no limit | 1,165 | 100% | 2 | 141 | 250 mg/L nuisance level |
| Radon 1984 to 2000 | no limit | 233 | 94% | 4,093 | 171,527 | 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 |
|---|---|---|---|---|
| Radium (226 + 228) | 21%1,012 samples | 39%212 samples | 10%353 samples | 7%307 samples |
| Copper | 0%703 samples | 0%124 samples | 4%357 samples | 4%307 samples |
| Lead | 20%354 samples | 7%123 samples | 7%357 samples | 3%307 samples |
| Nitrate | 14%522 samples | 1%90 samples | 2%330 samples | n/a |
| Uranium | 67%66 samples | 80%20 samples | 62%358 samples | 53%307 samples |
| Arsenic | 9%501 samples | 19%116 samples | n/a | n/a |
Uranium above the limit in Stevens County fell from 62% of 358 samples in the 2010s to 53% of 307 in the 2020s.
Arsenic above the limit in Stevens County rose from 9% of 501 samples before 2000 to 19% of 116 in the 2000s.
Radium (226 + 228), copper, lead, nitrate 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 uranium (59% of 751 samples), radium (226 + 228) (19% of 1,884 samples), and arsenic (11% of 623 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.
Iron, Manganese, and Chloride are widespread in local groundwater. They are mainly a staining and taste problem, but high manganese also carries a health advisory for infants.
The median radon reading (4,093 pCi/L) is above the 2,000 pCi/L level at which treatment is recommended. Radon in water raises indoor air radon when it is used for showers and laundry.
What to test for in Stevens County
- 1Uranium59% of 751 local samples were above the limit.
- 2Radium (226 + 228)19% of 1,884 local samples were above the limit.
- 3Arsenic11% of 623 local samples were above the limit.
- 4Lead10% of 1,141 local samples were above the limit.
- 5Fluoride9% of 341 local samples were above the limit.
- 6Nitrate9% of 942 local samples were above the limit.
- 7Copper2% of 1,491 local samples were above the limit.
- 8Volatile organic compounds (VOCs)2 reported spills and releases on record locally.
Test your Stevens County well for uranium, radium (226 + 228) and arsenic
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 Washington: certified labs, state programs and prices.
Already have results back? Get your lab report read against the Stevens County numbers, $29. Every line explained, ranked by what matters, with the fix for each.
Wells in Stevens County
7,387 domestic wells in Stevens County are on record with the state since 1983. the typical well is 220 feet deep (one in ten goes past 500 feet).
In a typical Stevens County well, the median yield is 8.3 gallons per minute, 17% of wells yield under 3 gallons per minute and usually need a storage tank.
Find your own well's report
The state keeps the driller's report for most wells drilled since 1984. It tells you how deep your well is, where bedrock starts, and how much water it makes, which decides what treatment can work.
- Open Ecology well report search and choose Water Well.
- It lists depth, casing, static water level, the yield test and the driller.
Washington has required well reports since 1971; reports are located only to the quarter-quarter section, so check the address on the scan.
The rock under Stevens County
Not a principal aquifer
The USGS map places this area outside any principal aquifer, which usually means wells here draw from fractured bedrock or thin local deposits rather than a large regional aquifer. Bedrock wells of that kind are where arsenic, radon and uranium turn up, and yields vary from well to well.
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 Washington
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.
- Drinking Water, Washington State Department of Health
- Environmental lab accreditation, Washington State Department of Ecology
Contamination sources on record in Stevens County
Washington Ecology facility interactions records 2 reported spills and releases in Stevens County, among 340 regulated sites in total. Groundwater does not follow property lines, so a well within a few hundred feet of one of these is worth testing for what that site could release.
- 2
- reported spills and releasesMost spills are fuel; a few are solvents or chemicals that reach the water table.
- 303
- other remediation projects
- 35
- other solid waste facilities
Treatment that fits the local profile
Uranium
Point-of-use reverse osmosis; Anion exchange; Whole-house anion exchange
Radium (226 + 228)
Water softener (cation exchange); Point-of-use reverse osmosis
Arsenic
Point-of-use reverse osmosis; Adsorptive media (iron-based) whole-house; Anion exchange
Lead
Point-of-use reverse osmosis; Certified lead-removal carbon filter; Neutralizing filter to raise pH and stop leaching
Fluoride
Point-of-use reverse osmosis; Activated alumina; Distillation
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 uranium
Under-sink reverse osmosis system
under-sink or countertop, about $300
Look for NSF/ANSI 58 certification listing the contaminant you need removed.
For uranium
Whole-house arsenic and uranium filter
whole-house, at the point of entry, about $2,500
Adsorptive iron-based media; sized to your well yield.
For arsenic
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 Stevens County
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Common questions
How deep are wells in Stevens County?
The typical domestic well in Stevens County is 220 feet deep, based on 7,387 wells reported to the state since 1983. One in ten is deeper than 500 feet.
Is there arsenic in well water in Stevens County?
Arsenic was detected in 92% of 623 public well samples in Stevens County, and 11% 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 Stevens County?
The median radon level across 233 public samples in Stevens County was 4,093 pCi/L, with a high of 171,527 pCi/L. New Hampshire recommends treatment above 2,000 pCi/L.
How often should I test a private well in Stevens 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 Stevens 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 Washington dataset as CSV, every county and town, with the sources named.
Sources
- USGS Water Quality Portal: 13,392 samples in Stevens 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.
- USGS national arsenic model (Ayotte 2017): estimated share of 21,243 people on private wells in Stevens 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.
- Washington Ecology well construction reports: 7,387 well records in Stevens County, 7,387 domestic. Well construction reports filed with the Washington State Department of Ecology, water wells only, located at the quarter-quarter section. Only aggregates are shown; owner names and addresses are never stored. Retrieved September 17, 2026.
- Washington Ecology facility interactions: 340 regulated sites located in Stevens County. Toxics cleanup sites, spills and solid waste facilities from the Washington State Department of Ecology Facility/Site register. Retrieved September 17, 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.