Well water in Dayton, Ohio
In Dayton, 1% of 67 tested well samples exceeded the EPA limit for nitrate (10 mg/L), based on public data from USGS Water Quality Portal.
The strongest signal is arsenic: 15% of 13 local samples were above the limit, too few samples to carry the headline but first on the test list below.
357 test results across 11 contaminants from at least 45 wells, 1976 to 2014; nitrate has the most at 67. Data refreshed September 3, 2026.
Compiled by Nick at Well Water Nerd from public records. How these pages are built
What individual samples found
Each row summarizes every public sample for that contaminant inside Dayton. 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 2002 to 2014 | 13 | 92% | 7.9 | 16.2 | 10 ug/L EPA limit | |
| Nitrate 1976 to 2003 | 67 | 70% | 0.18 | 10.6 | 10 mg/L EPA limit | |
| Fluoride 1980 to 2014 | 35 | 100% | 0.3 | 0.41 | 4 mg/L EPA limit | |
| Lead 1997 to 2014 | 14 | 43% | 0 | 11 | 15 ug/L EPA limit | |
| Copper 1997 to 2014 | 14 | 71% | 0.001 | 0.014 | 1.3 mg/L EPA limit | |
| Sodium 1976 to 2014 | no limit | 51 | 100% | 30 | 160 | 20 mg/L health guideline |
| Manganese 1976 to 2014 | no limit | 51 | 94% | 110 | 590 | 300 ug/L health guideline |
| Iron 1976 to 2014 | no limit | 51 | 100% | 930 | 10,000 | 300 ug/L nuisance level |
| Chloride 1976 to 2014 | no limit | 51 | 100% | 59 | 300 | 250 mg/L nuisance level |
Sampled fewer than 10 times, too few to summarize: Uranium (5), E. coli (5).
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 | 2%57 samples | 0%10 samples | n/a | n/a |
Closer than the town
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 arsenic (15% of 13 samples) and nitrate (1% of 67 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.
Manganese, Iron, 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.
What to test for in Dayton
- 1Arsenic15% of 13 local samples were above the limit.
- 2Nitrate1% of 67 local samples were above the limit.
- 3Coliform bacteriaRecommended for every private well, every year.
- 4FluorideDetected in 100% of local samples.
- 5IronDetected in 100% of local samples.
- 6ChlorideDetected in 100% of local samples.
- 7ManganeseDetected in 94% of local samples.
- 8Volatile organic compounds (VOCs)782 leaking underground storage tank sites on record locally.
- 9Metals panel47 hazardous waste sites on record locally.
Test your Dayton well for arsenic, nitrate and coliform bacteria
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 Ohio: certified labs, state programs and prices.
Already have results back? Get your lab report read against the Dayton numbers, $29. Every line explained, ranked by what matters, with the fix for each.
Wells in Dayton
179 domestic wells in Dayton are on record with the state since 1971. 26% are drilled into bedrock, and the typical well is 72 feet deep (one in ten goes past 118 feet).
In a typical Dayton well, bedrock starts about 24 feet down, the median yield is 13.5 gallons per minute, 4% 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 ODNR water well log search and choose Water Well.
- The log lists depth, depth to bedrock, casing, static water level, the pump test and the driller.
Ohio has required well logs since 1948, so most drilled wells have one.
The rock under Dayton
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 town centroid. A single well can sit in a different unit, especially near a boundary.
Official help in Ohio
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 Water Systems Program, Ohio Department of Health
- Laboratory Certification, Ohio EPA
Contamination sources on record in Dayton
Ohio EPA records 782 leaking underground storage tank sites and 47 hazardous waste sites in Dayton, among 857 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.
- 782
- leaking underground storage tank sitesGasoline and heating oil that leaked from tanks move through groundwater as benzene, MTBE and other volatile organic compounds.
- 47
- hazardous waste sitesSolvents, degreasers and metals from industrial sites can travel far in fractured bedrock.
- 8
- lined landfills and transfer facilities
- 20
- other remediation projects
Treatment that fits the local profile
Arsenic
Point-of-use reverse osmosis; Adsorptive media (iron-based) whole-house; Anion exchange
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 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.
For manganese
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 Dayton
No water treatment company serves Dayton 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 Dayton, and you get an email naming it first.
Common questions
How deep are wells in Dayton?
The typical domestic well in Dayton is 72 feet deep, based on 179 wells reported to the state since 1971. One in ten is deeper than 118 feet. 26% are drilled into bedrock.
Is there arsenic in well water in Dayton?
Arsenic was detected in 92% of 13 public well samples in Dayton, and 15% 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 Dayton?
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.
Towns near Dayton
Closest first. Groundwater does not stop at a line on a map, so the next town over is a fair second opinion.
Want the numbers themselves? Download the Ohio dataset as CSV, every county and town, with the sources named.
Sources
- USGS Water Quality Portal: 357 samples in Dayton. Data from the Water Quality Portal, a service of USGS, EPA and USDA; groundwater samples collected by USGS and cooperators. Retrieved September 3, 2026.
- Ohio DNR water well logs: 1,383 well records in Dayton, 179 domestic. Water well logs filed with the Ohio Department of Natural Resources Division of Water Resources since 1948. Only aggregates are shown; owner names and addresses are never stored. Retrieved September 17, 2026.
- Ohio EPA regulated sites: 857 regulated sites located in Dayton. Remediation sites, leaking underground storage tank releases (BUSTR) and landfills from the Ohio Environmental Protection Agency and the Division of State Fire Marshal. 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.