Quick answer
About 1,926,000 people in Florida (10.2% of residents) got their water from private wells in 2010, according to USGS estimates. Florida Department of Health runs the state’s private well guidance. Florida DOH says that in some cases the county health department may be able to test private wells for certain toxic substances free of charge.
- People on private wells
- 1,925,991
- Share of residents
- 10.2%
- Rank among states
- 4th
- Well users modeled above 10 µg/L arsenic
- 1.6%
Where to get your well tested in Florida
- Florida Department of Health: Private Well Water Testing, the state’s guidance for private well owners.
- Well water testing in Florida: what to test for and how to collect a sample.
- Certified laboratories in Florida. Use a lab certified for drinking water, so results are reliable.
Free or low-cost testing
Florida DOH says that in some cases the county health department may be able to test private wells for certain toxic substances free of charge. (source)
Mail-in lab kits are another option when no local lab is convenient. See well water test kits for what home kits can and can’t tell you.
What to test for
- Every year: total coliform bacteria and nitrate.
- Before buying equipment: pH, hardness, iron, manganese and, if there’s a smell, hydrogen sulfide.
- Based on location: arsenic, uranium and radon, PFAS, and lead in older plumbing.
Private wells by county
Estimated people relying on private wells in each Florida county in 2010, the share of residents that represents, and the modeled share of well users with arsenic above 10 µg/L. These are USGS model estimates (2010 population), not measurements of any well. Arsenic is hidden for counties with fewer than 500 well users.
| County | People on wells | Share | Arsenic >10 µg/L |
|---|---|---|---|
| Hillsborough County | 131,641 | 10.7% | 1.4% |
| Marion County | 97,040 | 29.3% | 1.0% |
| Duval County | 89,802 | 10.4% | 1.8% |
| Polk County | 84,864 | 14.1% | 1.1% |
| Palm Beach County | 82,048 | 6.2% | 1.4% |
| Pasco County | 61,341 | 13.2% | 2.4% |
| Orange County | 58,400 | 5.1% | 1.1% |
| Lake County | 55,227 | 18.6% | 1.0% |
| Volusia County | 54,766 | 11.1% | 1.2% |
| Putnam County | 47,851 | 64.3% | 1.4% |
| Miami-Dade County | 46,887 | 1.9% | 2.9% |
| St. Lucie County | 46,013 | 16.6% | 1.3% |
Show all 67 counties
| Citrus County | 44,178 | 31.3% | 2.3% |
| Lee County | 43,444 | 7.0% | 1.5% |
| Sarasota County | 43,030 | 11.3% | 1.6% |
| Alachua County | 39,290 | 15.9% | 1.0% |
| Brevard County | 38,112 | 7.0% | 1.7% |
| Bay County | 36,474 | 21.6% | 4.0% |
| Martin County | 35,571 | 24.3% | 2.1% |
| Columbia County | 35,227 | 52.2% | 1.0% |
| Clay County | 35,180 | 18.4% | 1.7% |
| St. Johns County | 33,565 | 17.7% | 1.4% |
| Collier County | 32,148 | 10.0% | 2.2% |
| Nassau County | 31,692 | 43.2% | 2.0% |
| Jackson County | 29,870 | 60.0% | 1.0% |
| Suwannee County | 28,702 | 69.1% | 1.5% |
| Indian River County | 28,136 | 20.4% | 1.8% |
| Seminole County | 27,343 | 6.5% | 1.1% |
| Levy County | 26,287 | 64.4% | 1.1% |
| Leon County | 24,830 | 9.0% | 2.1% |
| Hernando County | 23,785 | 13.8% | 3.5% |
| Sumter County | 22,940 | 24.6% | 2.1% |
| Osceola County | 22,782 | 8.5% | 1.1% |
| Manatee County | 20,719 | 6.4% | 1.7% |
| Highlands County | 19,905 | 20.1% | 1.1% |
| Broward County | 19,571 | 1.1% | 2.0% |
| Walton County | 19,295 | 35.1% | 2.4% |
| Baker County | 18,704 | 69.0% | 1.0% |
| Bradford County | 16,674 | 58.5% | 1.1% |
| Okeechobee County | 16,511 | 41.3% | 1.1% |
| Washington County | 15,625 | 62.8% | 1.8% |
| Gadsden County | 15,477 | 33.4% | 1.5% |
| Wakulla County | 14,496 | 47.1% | 2.2% |
| DeSoto County | 14,378 | 41.2% | 2.4% |
| Gilchrist County | 13,859 | 81.8% | 1.0% |
| Hardee County | 13,539 | 48.8% | 1.0% |
| Taylor County | 13,303 | 58.9% | 1.5% |
| Hendry County | 12,542 | 32.0% | 3.4% |
| Holmes County | 12,491 | 62.7% | 1.4% |
| Dixie County | 11,372 | 69.2% | 1.5% |
| Madison County | 11,316 | 58.9% | 1.4% |
| Jefferson County | 10,183 | 69.0% | 1.0% |
| Charlotte County | 9,539 | 6.0% | 3.3% |
| Calhoun County | 9,352 | 63.9% | 2.0% |
| Union County | 8,952 | 57.6% | 1.0% |
| Gulf County | 8,600 | 54.2% | 2.0% |
| Santa Rosa County | 8,464 | 5.6% | 1.7% |
| Hamilton County | 8,166 | 55.2% | 1.9% |
| Okaloosa County | 8,027 | 4.4% | 1.8% |
| Lafayette County | 6,867 | 77.4% | 1.7% |
| Pinellas County | 6,529 | 0.7% | 2.8% |
| Flagler County | 5,965 | 6.2% | 1.2% |
| Glades County | 4,751 | 36.9% | 2.8% |
| Liberty County | 4,557 | 54.5% | 2.3% |
| Escambia County | 3,287 | 1.1% | 2.6% |
| Franklin County | 2,467 | 21.4% | 2.5% |
| Monroe County | 2,042 | 2.8% | 4.3% |
After you get results
Enter your numbers in the test results tool to see what needs treating and in what order. The guide to reading a well water test explains units and limits.
Common questions
Does Florida offer free well water testing?
Florida DOH says that in some cases the county health department may be able to test private wells for certain toxic substances free of charge.
Who oversees private wells in Florida?
Florida Department of Health (Private Well Water Testing) publishes guidance for private well owners. Private wells aren’t covered by the federal Safe Drinking Water Act, so testing and treatment are up to the owner.
How many people use private wells in Florida?
USGS estimates about 1,926,000 people, or 10.2% of the population in 2010. That ranks 4th of the states covered by the estimate.
What should I test my well for in Florida?
Test every year for total coliform bacteria and nitrate, plus pH, hardness, iron and manganese before buying equipment. Ask the state program or a certified lab about local concerns such as arsenic, uranium or PFAS.
Sources
- Florida Department of Health: Private Well Water Testing
- Florida Department of Health: well water testing
- Florida certified laboratories
- Florida free or low-cost testing
- USGS data release: domestic well locations and populations served, 2000 and 2010 (Johnson, Belitz and Lombard, 2019)
- CDC Environmental Public Health Tracking: private well water data (from USGS)