Tap & Air

Private wells

Alabama well water: who's on a well and what to test for

An estimated 1,014,200 people in 470,200 homes, about 20.5% of Alabama homes, above the national 14.6%. Estimates are from EPA's Water Source 2020 model.

People on private wells

1,014,200

Homes on wells

20.5%

Est. above arsenic limit

2,600

Butler County: about 43% of homes on private wellsCoffee County: about 29% of homes on private wellsMorgan County: about 14% of homes on private wellsBaldwin County: about 18% of homes on private wellsLowndes County: about 61% of homes on private wellsFayette County: about 53% of homes on private wellsWinston County: about 57% of homes on private wellsChilton County: about 46% of homes on private wellsJefferson County: about 3% of homes on private wellsClay County: about 65% of homes on private wellsChambers County: about 29% of homes on private wellsSt. Clair County: about 25% of homes on private wellsLauderdale County: about 24% of homes on private wellsDeKalb County: about 45% of homes on private wellsGreene County: about 49% of homes on private wellsCherokee County: about 48% of homes on private wellsColbert County: about 19% of homes on private wellsMontgomery County: about 4% of homes on private wellsEtowah County: about 16% of homes on private wellsFranklin County: about 42% of homes on private wellsElmore County: about 27% of homes on private wellsPerry County: about 47% of homes on private wellsCalhoun County: about 13% of homes on private wellsDallas County: about 30% of homes on private wellsConecuh County: about 61% of homes on private wellsChoctaw County: about 69% of homes on private wellsSumter County: about 45% of homes on private wellsRandolph County: about 64% of homes on private wellsLimestone County: about 22% of homes on private wellsMarshall County: about 19% of homes on private wellsBullock County: about 46% of homes on private wellsRussell County: about 15% of homes on private wellsShelby County: about 9% of homes on private wellsClarke County: about 47% of homes on private wellsMarengo County: about 47% of homes on private wellsHale County: about 54% of homes on private wellsLamar County: about 52% of homes on private wellsPickens County: about 56% of homes on private wellsCoosa County: about 68% of homes on private wellsWalker County: about 35% of homes on private wellsWashington County: about 73% of homes on private wellsCrenshaw County: about 61% of homes on private wellsDale County: about 28% of homes on private wellsLee County: about 11% of homes on private wellsAutauga County: about 22% of homes on private wellsBarbour County: about 35% of homes on private wellsMobile County: about 16% of homes on private wellsBibb County: about 48% of homes on private wellsPike County: about 31% of homes on private wellsGeneva County: about 52% of homes on private wellsHouston County: about 22% of homes on private wellsMarion County: about 44% of homes on private wellsCleburne County: about 69% of homes on private wellsMadison County: about 5% of homes on private wellsWilcox County: about 56% of homes on private wellsBlount County: about 47% of homes on private wellsLawrence County: about 40% of homes on private wellsTuscaloosa County: about 12% of homes on private wellsMacon County: about 36% of homes on private wellsTallapoosa County: about 35% of homes on private wellsJackson County: about 42% of homes on private wellsCovington County: about 44% of homes on private wellsMonroe County: about 44% of homes on private wellsTalladega County: about 32% of homes on private wellsHenry County: about 51% of homes on private wellsEscambia County: about 33% of homes on private wellsCullman County: about 29% of homes on private wells
Homes on private wellsUnder 5%5-15%15-30%30-50%50% or more

Every Alabama county

Sorted by people on private wells. Arsenic and nitrate are modeled for typical wells in the county, not measured at yours; depth is the median of domestic well records.

Mobile County72,20016%2.0%0.2n/a
Baldwin County46,50018%1.7%0.898 ft
DeKalb County30,80045%3.3%1.4n/a
Tuscaloosa County27,80012%2.2%0.2n/a
Blount County27,40047%2.4%0.9n/a
Talladega County27,00032%1.0%0.5n/a
Cullman County25,40029%3.0%1.3n/a
Houston County25,30022%1.2%0.7n/a
Lauderdale County23,50024%1.1%1.1n/a
St. Clair County23,10025%1.5%0.3n/a
Elmore County22,40027%1.1%0.2134 ft
Jackson County22,40042%2.9%0.6n/a
Walker County22,10035%2.5%0.2n/a
Limestone County22,00022%1.2%1.0n/a
Madison County20,7005%1.2%2.0n/a
Lee County20,50011%1.0%0.5n/a
Chilton County20,40046%1.2%0.2110 ft
Jefferson County20,3003%2.0%0.3n/a
Shelby County18,2009%1.4%0.2n/a
Morgan County17,50014%2.9%0.9n/a
Marshall County17,30019%2.8%1.2n/a
Covington County16,70044%1.3%0.1n/a
Etowah County16,40016%1.5%0.5n/a
Calhoun County15,90013%1.4%0.8n/a
Coffee County14,70029%1.5%0.2n/a
Tallapoosa County14,10035%1.3%0.375 ft
Randolph County14,00064%1.4%0.6n/a
Dale County13,90028%2.1%0.2n/a
Geneva County13,80052%1.4%0.2n/a
Winston County13,40057%2.7%0.3n/a
Lawrence County13,30040%1.8%0.7n/a
Cherokee County12,90048%2.4%0.5n/a
Franklin County12,70042%1.8%0.4n/a
Marion County12,40044%2.0%0.3n/a
Autauga County12,20022%1.1%0.2n/a
Escambia County11,70033%1.0%0.7n/a
Bibb County11,40048%1.4%0.1130 ft
Dallas County11,20030%1.7%0.0n/a
Pickens County10,90056%1.7%0.1n/a
Washington County10,90073%1.0%0.1n/a
Colbert County10,90019%1.6%1.7n/a
Cleburne County10,60069%1.5%0.3102 ft
Pike County10,50031%1.0%0.3n/a
Clarke County10,40047%1.0%0.1200 ft
Chambers County9,60029%1.3%0.3n/a
Clay County9,20065%1.3%0.3100 ft
Barbour County8,70035%1.2%0.5n/a
Choctaw County8,70069%0.9%0.0n/a
Russell County8,60015%1.0%0.3n/a
Marengo County8,60047%1.2%0.0n/a
Fayette County8,60053%2.0%0.2n/a
Henry County8,50051%1.2%2.2n/a
Monroe County8,40044%1.4%0.3n/a
Montgomery County8,3004%1.2%0.0n/a
Butler County8,10043%2.2%0.1n/a
Crenshaw County8,00061%1.7%0.3n/a
Hale County7,60054%1.3%0.0n/a
Lamar County7,40052%1.5%0.1n/a
Macon County6,90036%1.0%0.3n/a
Coosa County6,60068%1.0%0.1101 ft
Conecuh County6,60061%1.0%0.1n/a
Lowndes County6,20061%2.5%0.0n/a
Wilcox County5,90056%1.5%0.0n/a
Sumter County5,10045%1.0%0.0n/a
Bullock County3,90046%0.9%0.0n/a
Perry County3,60047%1.2%0.0n/a
Greene County3,40049%1.3%0.0n/a

Shading: red is among the highest counties nationally, amber the middle, green the lower range. Click a column to sort.

Most well users above the arsenic limit

Test first, then treat what the test finds

We may earn a commission from links below, at no cost to you. Picks follow the testing order, not who pays. How we make money.

1. Certified lab well test

Start here, every year

A mail-in kit analyzed by a certified lab measures bacteria, nitrate, arsenic, metals and more. Test strips cannot measure arsenic or uranium reliably.

Mail-in certified lab well water test$$

2. Sediment pre-filter

Sand, silt or cloudy water

A 5-micron cartridge after the pressure tank catches sand, silt and rust before they reach fixtures or other filters. Cartridges are cheap and swap every few months.

5-micron whole-house sediment filter$

3. Iron and sulfur filter

Orange stains or rotten-egg smell

Air-injection or oxidizing-media filters remove orange staining and rotten-egg smell. Size one from a lab result for iron, manganese and hydrogen sulfide.

Air-injection iron and sulfur filter$$$

4. UV disinfection system

Coliform bacteria in a test

Inactivates bacteria and viruses; usually for private wells or after boil notices.

12 GPM whole-house UV purifier$$$

5. Under-sink reverse osmosis

Arsenic, nitrate or uranium in a test

The most thorough option for drinking water: PFAS, lead, nitrate, arsenic and more. Look for NSF/ANSI 58.

Waterdrop G3P600 tankless RO$$$ iSpring RCC7AK reverse osmosis$$

6. Whole-house well filter

Several problems at once

Multi-stage sediment and carbon for every tap. Add UV if bacteria shows up, and choose stages from your lab results, not a guess.

Waterdrop WHF21 2-stage whole-house filter$$
Get free well water treatment quotes

Questions

Which Alabama counties rely most on wells?+

By share of homes: Washington County (73%), Choctaw County (69%), Cleburne County (69%), Coosa County (68%), Clay County (65%). By number of people: Mobile County (72,200), Baldwin County (46,500), DeKalb County (30,800).

Is arsenic a problem in Alabama wells?+

USGS estimates about 2,600 Alabama well users have water above the 10 microgram per liter arsenic limit that applies to public systems, the largest numbers in Chambers County, Baldwin County, Mobile County. Arsenic has no taste or smell, so only a lab test finds it.

Do I have to test my well when I sell a house in Alabama?+

We could not confirm a statewide rule for Alabama. Check with your county health department. Buyers can still make a lab test a condition of the offer.

How often should I test my well?+

No federal law covers private wells. EPA's drinking water limits apply to public water systems, so testing and treating a private well is up to the owner. EPA and CDC recommend testing at least once a year for coliform bacteria, nitrate, pH and total dissolved solids, and testing for arsenic, uranium, radon and other local concerns based on where you live.

Well-user counts, arsenic and nitrate figures are each a modeled estimate built from national datasets, not a count of tested wells, and well depths summarize drilling records rather than every well. Your own well can be very different from the county average, which is why the only answer for your home is a lab test. Sources: EPA Office of Research and Development, Water Source 2020 (private well estimates by census block); CDC Environmental Public Health Tracking, Well Water Index (from USGS nitrate and arsenic models); USGS, county-level domestic well population with arsenic above 10 micrograms per liter (Ayotte and others, 2017); USGS Synthesized Domestic Well Database for the Conterminous United States (SynDWell-US), McCarthy and others, 2025 (depth, where a county has 30+ usable records).