Well water in Apache County, Arizona

1in5

Testing strongly recommended

tested well samples in Apache County exceeded the EPA limit for arsenic (10 ug/L), based on public data from USGS Water Quality Portal.

5,352 test results across 13 contaminants from at least 644 wells, 1933 to 2026; nitrate has the most at 1,141. Data refreshed September 15, 2026.

Compiled by Nick at Well Water Nerd from public records. How these pages are built

An estimated 22,620 people in Apache County get their drinking water from a private well, per USGS 2015 county water use. That is about 32% of residents.

Separately, the USGS national arsenic model estimates that 7% of the 22,620 people on private wells in Apache County draw water above 10 ug/L (the model's range is 5% to 9%), from geology and well depth rather than local tests.

What individual samples found

Each row summarizes every public sample for that contaminant inside Apache 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
Arsenic 1985 to 2017	21%	119	70%	1	53	10 ug/L EPA limit
Uranium 1986 to 2017	6%	32	97%	6.5	38	30 ug/L EPA limit
Nitrate 1933 to 2026	3%	1,141	83%	0.223	97	10 mg/L EPA limit
Radium (226 + 228) 1986 to 2017	2%	41	73%	0	17	5 pCi/L EPA limit
Fluoride 1933 to 2017	2%	971	98%	0.6	27	4 mg/L EPA limit
Copper 1966 to 2017	0%	105	62%	0.001	0.076	1.3 mg/L EPA limit
Lead 1985 to 2017	0%	94	21%	0	11	15 ug/L EPA limit
Chloride 1933 to 2017	no limit	1,064	100%	32	51,000	250 mg/L nuisance level
Sodium 1933 to 2017	no limit	718	100%	94	24,000	20 mg/L health guideline
Iron 1948 to 2026	no limit	718	75%	40	130,000	300 ug/L nuisance level
Manganese 1958 to 2026	no limit	337	81%	20.4	2,120	300 ug/L health guideline

Sampled fewer than 10 times, too few to summarize: E. coli (5), Radon (7).

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	3%1,016 samples	0%68 samples	0%37 samples	0%20 samples
Fluoride	2%898 samples	0%48 samples	0%25 samples	n/a
Arsenic	26%50 samples	16%43 samples	19%26 samples	n/a
Copper	0%50 samples	0%37 samples	0%18 samples	n/a
Lead	0%39 samples	0%37 samples	0%18 samples	n/a
Uranium	13%16 samples	0%12 samples	n/a	n/a

Nitrate, fluoride, arsenic, copper, lead 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 address

What this means

The contaminants most often above their limit here are arsenic (21% of 119 samples), uranium (6% of 32 samples), and nitrate (3% of 1,141 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 Apache County

1
Arsenic
21% of 119 local samples were above the limit.
2
Uranium
6% of 32 local samples were above the limit.
3
Nitrate
3% of 1,141 local samples were above the limit.
4
Radium (226 + 228)
2% of 41 local samples were above the limit.
5
Fluoride
2% of 971 local samples were above the limit.
6
Coliform bacteria
Recommended for every private well, every year.
7
Radon
Median local reading is 440 pCi/L.
8
Volatile organic compounds (VOCs)
57 leaking underground storage tank sites on record locally.

Test your Apache County well for arsenic, uranium and 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 $209 Already 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 Arizona: certified labs, state programs and prices.

Already have results back? Get your lab report read against the Apache County numbers, $29. Every line explained, ranked by what matters, with the fix for each.

Wells in Apache County

5,624 domestic wells in Apache County are on record with the state since 1970. the typical well is 260 feet deep (one in ten goes past 600 feet).

In a typical Apache County well, the median yield is 12 gallons per minute, 4% of wells yield under 3 gallons per minute and usually need a storage tank.

391

1970s

700

1980s

787

1990s

898

2000s

168

2010s

2020s

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 ADWR Wells55 registry and choose Water Well.
The record lists depth, water level, casing depth and the tested rate, plus a link to the drilling log.

Arizona has registered wells since 1980; earlier wells often have no record.

The rock under Apache County

Colorado Plateaus aquifers

Sandstone. Sandstone wells draw from pore space in the rock and tend to be dependable. Iron, manganese and hardness are common, and some sandstones carry arsenic or radium, so a first test should include both.

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 Arizona

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.

Well Water, ADHS
Licensed Commercial Drinking Water Laboratories, ADHS

Contamination sources on record in Apache County

ADEQ records 57 leaking underground storage tank sites in Apache County, among 58 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.

57: leaking underground storage tank sitesGasoline and heating oil that leaked from tanks move through groundwater as benzene, MTBE and other volatile organic compounds.
1: lined landfill or transfer facility

Treatment that fits the local profile

Arsenic

Point-of-use reverse osmosis; Adsorptive media (iron-based) whole-house; Anion exchange

Uranium

Point-of-use reverse osmosis; Anion exchange; Whole-house anion exchange

Nitrate

Point-of-use reverse osmosis; Anion exchange; Distillation

Radium (226 + 228)

Water softener (cation exchange); Point-of-use reverse osmosis

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 arsenic

Under-sink reverse osmosis system

under-sink or countertop, about $300

Look for NSF/ANSI 58 certification listing the contaminant you need removed.

For arsenic

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.

Free, no obligation

Get on the list for a free in-home water test in Apache County

No water treatment company serves Apache 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 Apache County, and you get an email naming it first.

Common questions

How deep are wells in Apache County?

The typical domestic well in Apache County is 260 feet deep, based on 5,624 wells reported to the state since 1970. One in ten is deeper than 600 feet.

Is there arsenic in well water in Apache County?

Arsenic was detected in 70% of 119 public well samples in Apache County, and 21% 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 often should I test a private well in Apache 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 Apache 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 Arizona dataset as CSV, every county and town, with the sources named.

Sources

USGS Water Quality Portal: 5,352 samples in Apache 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 22,620 people on private wells in Apache 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.
Arizona ADWR well registry (Wells55): 7,712 well records in Apache County, 5,624 domestic. Registered wells from the Arizona Department of Water Resources Wells55 registry. Only aggregates are shown; owner names and addresses are never stored. Retrieved September 18, 2026.
ADEQ regulated sites: 58 regulated sites located in Apache County. Leaking underground storage tank sites and municipal landfills from the Arizona Department of Environmental Quality. 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.