Well water in Duval County, Florida
In Duval County, <1% of 256 tested well samples exceeded the EPA limit for lead (15 ug/L), based on public data from USGS Water Quality Portal.
8,562 test results across 13 contaminants from at least 157 wells, 1925 to 2024; chloride has the most at 4,623. Data refreshed September 15, 2026.
Compiled by Nick at Well Water Nerd from public records. How these pages are built
An estimated 144,322 people in Duval County get their drinking water from a private well, per USGS 2015 county water use. That is about 16% of residents.
Separately, the USGS national arsenic model estimates that <1% of the 144,322 people on private wells in Duval County draw water above 10 ug/L (the model's range is <1% to 1%), from geology and well depth rather than local tests.
What individual samples found
Each row summarizes every public sample for that contaminant inside Duval 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 |
|---|---|---|---|---|---|---|
| Lead 1980 to 2024 | 256 | 100% | 0.05 | 200 | 15 ug/L EPA limit | |
| Nitrate 1940 to 2015 | 652 | 31% | 0 | 15.7 | 10 mg/L EPA limit | |
| Fluoride 1941 to 2024 | 792 | 98% | 0.65 | 21 | 4 mg/L EPA limit | |
| Arsenic 1979 to 2024 | 258 | 99% | 0.5 | 5.82 | 10 ug/L EPA limit | |
| Copper 1979 to 2024 | 257 | 100% | 0.001 | 0.06 | 1.3 mg/L EPA limit | |
| Chloride 1925 to 2024 | no limit | 4,623 | 100% | 25 | 6,800 | 250 mg/L nuisance level |
| Sodium 1930 to 2024 | no limit | 1,067 | 100% | 15.9 | 3,400 | 20 mg/L health guideline |
| Iron 1925 to 2024 | no limit | 368 | 97% | 34.6 | 44,200 | 300 ug/L nuisance level |
| Manganese 1952 to 2024 | no limit | 283 | 99% | 2.88 | 1503 | 300 ug/L health guideline |
Sampled fewer than 10 times, too few to summarize: E. coli (2), Radium (226 + 228) (2), Uranium (1), Radon (1).
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 |
|---|---|---|---|---|
| Fluoride | <1%487 samples | 0%236 samples | 0%62 samples | n/a |
| Nitrate | 0%50 samples | <1%600 samples | n/a | n/a |
| Lead | n/a | 0%74 samples | 0%97 samples | 0%80 samples |
| Arsenic | n/a | 0%74 samples | 0%97 samples | 0%80 samples |
| Copper | n/a | 0%74 samples | 0%97 samples | 0%80 samples |
Fluoride, nitrate, lead, arsenic, 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 lead (<1% of 256 samples), nitrate (<1% of 652 samples), and fluoride (<1% of 792 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 Duval County
- 1Lead<1% of 256 local samples were above the limit.
- 2Nitrate<1% of 652 local samples were above the limit.
- 3Fluoride<1% of 792 local samples were above the limit.
- 4Coliform bacteriaRecommended for every private well, every year.
- 5RadonMedian local reading is 60 pCi/L.
- 6ChlorideDetected in 100% of local samples.
- 7CopperDetected in 100% of local samples.
- 8Volatile organic compounds (VOCs)2,486 leaking underground storage tank sites on record locally.
- 9Metals panel10 hazardous waste sites on record locally.
Test your Duval County well for lead, nitrate and fluoride
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 Florida: certified labs, state programs and prices.
Already have results back? Get your lab report read against the Duval County numbers, $29. Every line explained, ranked by what matters, with the fix for each.
The rock under Duval County
Surficial aquifer system
Unconsolidated sand and gravel. Wells in sand and gravel are usually shallow and productive, and they recharge quickly from the surface. That makes them the most exposed to nitrate, bacteria and anything spilled nearby, and the least likely to carry arsenic or radon from the rock.
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 Florida
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 Well Water Testing, Florida Department of Health
- NELAP Certified Laboratory Search, Florida DEP
Contamination sources on record in Duval County
FDEP records 2,486 leaking underground storage tank sites and 10 hazardous waste sites in Duval County, among 3,324 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.
- 2,486
- leaking underground storage tank sitesGasoline and heating oil that leaked from tanks move through groundwater as benzene, MTBE and other volatile organic compounds.
- 10
- hazardous waste sitesSolvents, degreasers and metals from industrial sites can travel far in fractured bedrock.
- 828
- other remediation projects
Treatment that fits the local profile
Lead
Point-of-use reverse osmosis; Certified lead-removal carbon filter; Neutralizing filter to raise pH and stop leaching
Nitrate
Point-of-use reverse osmosis; Anion exchange; Distillation
Fluoride
Point-of-use reverse osmosis; Activated alumina; 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 lead
Under-sink reverse osmosis system
under-sink or countertop, about $300
Look for NSF/ANSI 58 certification listing the contaminant you need removed.
For lead
Acid neutralizing filter
whole-house, at the point of entry, about $1,200
Raises pH so plumbing stops leaching lead and copper.
For lead
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.
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Common questions
Is there arsenic in well water in Duval County?
Arsenic was detected in 99% of 258 public well samples in Duval County, and 0% 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 Duval 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 Duval 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 Florida dataset as CSV, every county and town, with the sources named.
Sources
- USGS Water Quality Portal: 8,562 samples in Duval 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 144,322 people on private wells in Duval 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.
- FDEP regulated sites: 3,324 regulated sites located in Duval County. Petroleum contamination discharges and cleanup sites from the Florida Department of Environmental Protection. 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.