Well water in Yukon-Koyukuk County, Alaska
In Yukon-Koyukuk County, 4% of 125 tested well samples exceeded the EPA limit for nitrate (10 mg/L), based on public data from USGS Water Quality Portal.
754 test results across 9 contaminants from at least 44 wells, 1948 to 1976; chloride has the most at 130. Data refreshed September 3, 2026.
Compiled by Nick at Well Water Nerd from public records. How these pages are built
An estimated 75 people in Yukon-Koyukuk County get their drinking water from a private well, per USGS 2015 county water use. That is about 1% of residents.
What individual samples found
Each row summarizes every public sample for that contaminant inside Yukon-Koyukuk 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 |
|---|---|---|---|---|---|---|
| Nitrate 1948 to 1976 | 125 | 100% | 0.294 | 66 | 10 mg/L EPA limit | |
| Fluoride 1948 to 1976 | 125 | 100% | 0.1 | 0.6 | 4 mg/L EPA limit | |
| Chloride 1948 to 1976 | no limit | 130 | 100% | 1.7 | 250 | 250 mg/L nuisance level |
| Iron 1948 to 1976 | no limit | 126 | 100% | 705 | 30,000 | 300 ug/L nuisance level |
| Sodium 1953 to 1976 | no limit | 123 | 100% | 5.2 | 280 | 20 mg/L health guideline |
| Manganese 1955 to 1976 | no limit | 107 | 98% | 100 | 5,000 | 300 ug/L health guideline |
Sampled fewer than 10 times, too few to summarize: Arsenic (6), Lead (6), Copper (6).
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 nitrate (4% of 125 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, Iron, and Manganese are widespread in local groundwater. They are mainly a staining and taste problem, but high manganese also carries a health advisory for infants.
What to test for in Yukon-Koyukuk County
- 1Nitrate4% of 125 local samples were above the limit.
- 2Coliform bacteriaRecommended for every private well, every year.
- 3ArsenicAbove the limit in 2 of 6 local samples; too few to quote a rate.
- 4FluorideDetected in 100% of local samples.
- 5ChlorideDetected in 100% of local samples.
- 6IronDetected in 100% of local samples.
- 7ManganeseDetected in 98% of local samples.
- 8Volatile organic compounds (VOCs)61 leaking underground storage tank sites on record locally.
- 9Metals panel388 hazardous waste sites on record locally.
Test your Yukon-Koyukuk County well for nitrate, coliform bacteria 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 Alaska: certified labs, state programs and prices.
Already have results back? Get your lab report read against the Yukon-Koyukuk County numbers, $29. Every line explained, ranked by what matters, with the fix for each.
Wells in Yukon-Koyukuk County
40 domestic wells in Yukon-Koyukuk County are on record with the state since 1984. 100% are drilled into bedrock, and the typical well is 171 feet deep (one in ten goes past 302 feet).
In a typical Yukon-Koyukuk County well, bedrock starts about 91 feet down, the median yield is 18.5 gallons per minute.
Bedrock wells are where arsenic, uranium and radon come from: the water sits in fractures in granite and metamorphic rock and picks up whatever the rock carries. That is why testing for those three matters more here than in a dug or gravel well.
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 Alaska DNR WELTS and choose Water Well.
- It lists depth, static water level, yield, depth to bedrock and the driller.
Alaska well logs are voluntary in most of the state, so many wells have none.
Contamination sources on record in Yukon-Koyukuk County
Alaska DEC contaminated sites records 61 leaking underground storage tank sites and 388 hazardous waste sites in Yukon-Koyukuk County, among 449 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.
- 61
- leaking underground storage tank sitesGasoline and heating oil that leaked from tanks move through groundwater as benzene, MTBE and other volatile organic compounds.
- 388
- hazardous waste sitesSolvents, degreasers and metals from industrial sites can travel far in fractured bedrock.
Treatment that fits the local profile
Nitrate
Point-of-use reverse osmosis; Anion exchange; Distillation
Iron
Oxidizing filter whole-house; Water softener (low levels); Aeration plus filtration
Manganese
Oxidizing filter (greensand, birm) whole-house; Water softener (low levels); Point-of-use reverse osmosis
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 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 iron
Iron and manganese oxidizing filter
whole-house, at the point of entry, about $1,800
Air-injection or greensand media; fixes staining at the source.
Free, no obligation
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No water treatment company serves Yukon-Koyukuk 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 Yukon-Koyukuk County, and you get an email naming it first.
Common questions
How deep are wells in Yukon-Koyukuk County?
The typical domestic well in Yukon-Koyukuk County is 171 feet deep, based on 40 wells reported to the state since 1984. One in ten is deeper than 302 feet. 100% are drilled into bedrock.
How often should I test a private well in Yukon-Koyukuk 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 Yukon-Koyukuk 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 Alaska dataset as CSV, every county and town, with the sources named.
Sources
- USGS Water Quality Portal: 754 samples in Yukon-Koyukuk 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.
- Alaska DNR well log tracking system (WELTS): 287 well records in Yukon-Koyukuk County, 40 domestic. Well logs filed with the Alaska Department of Natural Resources (WELTS). Only aggregates are shown; owner names and addresses are never stored. Retrieved September 18, 2026.
- Alaska DEC contaminated sites: 449 regulated sites located in Yukon-Koyukuk County. Contaminated sites, including leaking tank sites, from the Alaska Department of Environmental Conservation. Retrieved September 18, 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.