Well water in Florida

Name: Private well water quality in Florida
Creator: Well Water Nerd
License: Public domain (US federal government data)

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Testing strongly recommended

tested well samples in Florida exceeded the EPA limit for PFOS (4 ng/L), based on public data from USGS Water Quality Portal.

262,133 test results across 15 contaminants from at least 8,667 wells, 1901 to 2026; chloride has the most at 60,690. Data refreshed September 15, 2026.

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

An estimated 2,460,295 people in Florida get their drinking water from a private well, per USGS 2015 county water use.

Separately, the USGS national arsenic model estimates that 2% of the 2,460,295 people on private wells in Florida draw water above 10 ug/L (the model's range is 1% to 3%), from geology and well depth rather than local tests.

What individual samples found

Each row summarizes every public sample for that contaminant inside Florida. 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
PFOS 2019 to 2020	71%	79	84%	11	100	4 ng/L EPA limit
PFOA 2019 to 2020	41%	79	81%	3.4	21	4 ng/L EPA limit
Radium (226 + 228) 1973 to 2022	11%	951	84%	0.599	110	5 pCi/L EPA limit
Nitrate 1901 to 2026	6%	26,064	79%	0.01	1,830	10 mg/L EPA limit
Arsenic 1969 to 2026	5%	14,852	90%	0.5	660	10 ug/L EPA limit
E. coli 2002 to 2024	3%	156	3%	0	2	0 MPN/100mL EPA limit
Lead 1917 to 2026	1%	14,799	89%	0.05	3,600	15 ug/L EPA limit
Uranium 1965 to 2026	<1%	1,151	75%	0.18	80,000	30 ug/L EPA limit
Fluoride 1901 to 2026	<1%	33,748	97%	0.23	22,200	4 mg/L EPA limit
Copper 1917 to 2026	<1%	14,171	90%	0.001	5.77	1.3 mg/L EPA limit
Chloride 1901 to 2026	no limit	60,690	100%	60	1,410,000	250 mg/L nuisance level
Sodium 1901 to 2026	no limit	39,704	100%	19.9	56,900	20 mg/L health guideline
Iron 1908 to 2026	no limit	29,623	97%	60	4,300,000	300 ug/L nuisance level
Manganese 1942 to 2026	no limit	25,584	96%	2.74	43,000	300 ug/L health guideline
Radon 1993 to 2019	no limit	482	100%	435	14,700	2,000 pCi/L health guideline

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%12,762 samples	0%2,019 samples	<1%8,106 samples	<1%10,861 samples
Nitrate	7%21,111 samples	3%2,820 samples	1%1,709 samples	<1%424 samples
Arsenic	7%4,458 samples	12%1,016 samples	3%4,368 samples	2%5,010 samples
Lead	3%4,497 samples	2%1,086 samples	<1%4,223 samples	<1%4,993 samples
Copper	<1%3,920 samples	<1%1,076 samples	0%4,182 samples	<1%4,993 samples
Uranium	1%356 samples	<1%356 samples	<1%369 samples	1%70 samples

Fluoride, nitrate, arsenic, lead, copper, uranium have held within a few points between the two most recent periods with enough samples.

What this means

The contaminants most often above their limit here are pfos (71% of 79 samples), pfoa (41% of 79 samples), and radium (226 + 228) (11% of 951 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 Florida

1
PFOS
71% of 79 local samples were above the limit.
2
PFOA
41% of 79 local samples were above the limit.
3
Radium (226 + 228)
11% of 951 local samples were above the limit.
4
Nitrate
6% of 26,064 local samples were above the limit.
5
Arsenic
5% of 14,852 local samples were above the limit.
6
E. coli
3% of 156 local samples were above the limit.
7
Lead
1% of 14,799 local samples were above the limit.
8
Volatile organic compounds (VOCs)
38,639 leaking underground storage tank sites on record locally.
9
Metals panel
102 hazardous waste sites on record locally.

Test your Florida well for PFOS, PFOA 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 $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 Florida: certified labs, state programs and prices.

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

Free, one email

Send me the Florida report

The numbers above, which tests to order and where, and the treatment that fits the local profile, in one email.

The rock under Florida

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 state 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 Florida

FDEP records 38,639 leaking underground storage tank sites and 102 hazardous waste sites in Florida, among 49,216 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.

38,639: leaking underground storage tank sitesGasoline and heating oil that leaked from tanks move through groundwater as benzene, MTBE and other volatile organic compounds.
102: hazardous waste sitesSolvents, degreasers and metals from industrial sites can travel far in fractured bedrock.
10,475: other remediation projects

Treatment that fits the local profile

PFOS

Granular activated carbon whole-house; Point-of-use reverse osmosis; Anion exchange

PFOA

Granular activated carbon whole-house; Point-of-use reverse osmosis; Anion exchange

Radium (226 + 228)

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

Nitrate

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

Arsenic

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

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 PFOS

Under-sink reverse osmosis system

under-sink or countertop, about $300

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

For PFOS

Whole-house PFAS carbon system

whole-house, at the point of entry, about $3,000

Granular activated carbon certified to NSF/ANSI 53 for PFOA and PFOS; replace media on schedule.

For PFOS

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 PFOA

Aquasana Claryum 3-Stage under-sink filter

under-sink or countertop, about $175

Certified to NSF/ANSI 53 to reduce 99% of lead and 99.7% of PFOA and PFOS at the tap. Not a fix for arsenic, nitrate or bacteria.

For PFOA

Aquasana HealthShield whole-house filter

whole-house, at the point of entry, about $2,099

Whole-house carbon system the maker certifies to reduce PFAS (PFOA and PFOS) and VOCs at every tap; a UV option adds bacteria protection.

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.

Common questions

Is there arsenic in well water in Florida?

Arsenic was detected in 90% of 14,852 public well samples in Florida, and 5% 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 Florida?

The median radon level across 482 public samples in Florida was 435 pCi/L, with a high of 14,700 pCi/L. New Hampshire recommends treatment above 2,000 pCi/L.

How often should I test a private well in Florida?

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 in Florida

Want the numbers themselves? Download the Florida dataset as CSV, every county and town, with the sources named.

Sources

USGS Water Quality Portal: 262,133 samples in Florida. 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 2,460,295 people on private wells in Florida 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: 49,216 regulated sites located in Florida. 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.