Well water in Cibola County, New Mexico
1in3
Testing strongly recommended
tested well samples in Cibola County exceeded the EPA limit for uranium (30 ug/L), based on public data from USGS Water Quality Portal.
3,004 test results across 15 contaminants from at least 425 wells, 1933 to 2023; chloride has the most at 620. Data refreshed September 15, 2026.
Compiled by Nick at Well Water Nerd from public records. How these pages are built
An estimated 14,555 people in Cibola County get their drinking water from a private well, per USGS 2015 county water use. That is about 53% of residents.
Separately, the USGS national arsenic model estimates that 4% of the 14,555 people on private wells in Cibola County draw water above 10 ug/L (the model's range is 3% to 5%), from geology and well depth rather than local tests.
What individual samples found
Each row summarizes every public sample for that contaminant inside Cibola 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 1959 to 2020 | 120 | 98% | 10.3 | 2,800 | 30 ug/L EPA limit | |
| Arsenic 1960 to 2020 | 120 | 82% | 1.1 | 150 | 10 ug/L EPA limit | |
| Radium (226 + 228) 1977 to 2017 | 52 | 100% | 0.6 | 23 | 5 pCi/L EPA limit | |
| Nitrate 1933 to 2017 | 499 | 92% | 0.76 | 75 | 10 mg/L EPA limit | |
| Fluoride 1933 to 2020 | 448 | 100% | 0.6 | 7.5 | 4 mg/L EPA limit | |
| Lead 1963 to 2020 | 94 | 51% | 0 | 1 | 15 ug/L EPA limit | |
| Copper 1963 to 2020 | 86 | 64% | 0 | 0.08 | 1.3 mg/L EPA limit | |
| Chloride 1933 to 2020 | no limit | 620 | 100% | 30.5 | 27,000 | 250 mg/L nuisance level |
| Iron 1952 to 2020 | no limit | 344 | 89% | 70 | 140,000 | 300 ug/L nuisance level |
| Sodium 1933 to 2020 | no limit | 319 | 100% | 120 | 12,000 | 20 mg/L health guideline |
| Manganese 1959 to 2020 | no limit | 274 | 82% | 10 | 2,400 | 300 ug/L health guideline |
| Radon 2016 to 2017 | no limit | 12 | 100% | 983 | 1,620 | 2,000 pCi/L health guideline |
Sampled fewer than 10 times, too few to summarize: PFOS (7), PFOA (7), E. coli (2).
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 | 11%458 samples | 0%18 samples | 9%23 samples | n/a |
| Fluoride | 2%392 samples | 0%15 samples | 3%40 samples | n/a |
| Uranium | 8%52 samples | 0%15 samples | 83%52 samples | n/a |
| Arsenic | 14%77 samples | 0%15 samples | 22%27 samples | n/a |
| Lead | 0%51 samples | 0%15 samples | 0%27 samples | n/a |
| Copper | 0%43 samples | 0%15 samples | 0%27 samples | n/a |
Uranium above the limit in Cibola County rose from 8% of 52 samples before 2000 to 83% of 52 in the 2010s.
Arsenic above the limit in Cibola County rose from 14% of 77 samples before 2000 to 22% of 27 in the 2010s.
Nitrate, fluoride, lead, copper 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 (39% of 120 samples), arsenic (14% of 120 samples), and radium (226 + 228) (13% of 52 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 Cibola County
- 1Uranium39% of 120 local samples were above the limit.
- 2Arsenic14% of 120 local samples were above the limit.
- 3Radium (226 + 228)13% of 52 local samples were above the limit.
- 4Nitrate10% of 499 local samples were above the limit.
- 5Fluoride2% of 448 local samples were above the limit.
- 6Coliform bacteriaRecommended for every private well, every year.
- 7RadonMedian local reading is 983 pCi/L.
Test your Cibola County well for uranium, arsenic and radium (226 + 228)
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 New Mexico: certified labs, state programs and prices.
Already have results back? Get your lab report read against the Cibola County numbers, $29. Every line explained, ranked by what matters, with the fix for each.
The rock under Cibola 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 New Mexico
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.
- Private Wells, NMED
- Laboratory Certification, NMED
Contamination sources on record in Cibola County
NMED storage tank facilities and landfills records 25 regulated sites in Cibola County, among 25 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.
- 25
- registered underground storage tank sitesRegistered tanks are regulated and inspected; they matter most when they are old or near a shallow well.
Treatment that fits the local profile
Uranium
Point-of-use reverse osmosis; Anion exchange; Whole-house anion exchange
Arsenic
Point-of-use reverse osmosis; Adsorptive media (iron-based) whole-house; Anion exchange
Radium (226 + 228)
Water softener (cation exchange); Point-of-use reverse osmosis
Nitrate
Point-of-use reverse osmosis; Anion exchange; Distillation
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 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
Get on the list for a free in-home water test in Cibola County
No water treatment company serves Cibola 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 Cibola County, and you get an email naming it first.
Common questions
Is there arsenic in well water in Cibola County?
Arsenic was detected in 82% of 120 public well samples in Cibola County, and 14% 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 Cibola County?
The median radon level across 12 public samples in Cibola County was 983 pCi/L, with a high of 1,620 pCi/L. New Hampshire recommends treatment above 2,000 pCi/L.
How often should I test a private well in Cibola 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 Cibola 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 New Mexico dataset as CSV, every county and town, with the sources named.
Sources
- USGS Water Quality Portal: 3,004 samples in Cibola 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 14,555 people on private wells in Cibola 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.
- NMED storage tank facilities and landfills: 25 regulated sites located in Cibola County. Underground storage tank facilities and permitted landfills from the New Mexico Environment Department. 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.