Tennessee well water by county: arsenic and nitrate
Modelled arsenic and nitrate for private-well users in every Tennessee county, what to test for, and where to find a certified lab. Private wells aren’t covered by the Safe Drinking Water Act.
All 95 counties
- Sevier CountyWell users 23,400Arsenic about 3 in 100Nitrate 0.2 mg/L
- McMinn CountyWell users 19,100Arsenic about 4 in 100Nitrate 0.6 mg/L
- Fayette CountyWell users 18,300Arsenic about 4 in 100Nitrate 0.1 mg/L
- Monroe CountyWell users 17,700Arsenic about 3 in 100Nitrate 0.9 mg/L
- Hawkins CountyWell users 15,300Arsenic about 6 in 100Nitrate 0.3 mg/L
- Weakley CountyWell users 15,100Arsenic about 3 in 100Nitrate 0.1 mg/L
- Bradley CountyWell users 14,900Arsenic about 2 in 100Nitrate 0.7 mg/L
- Coffee CountyWell users 14,400Arsenic about 2 in 100Nitrate 1.3 mg/L
- Cocke CountyWell users 14,100Arsenic about 3 in 100Nitrate 0.2 mg/L
- Madison CountyWell users 14,000Arsenic about 2 in 100Nitrate 0.5 mg/L
- Knox CountyWell users 13,600Arsenic about 2 in 100Nitrate 0.4 mg/L
- Henry CountyWell users 13,100Arsenic about 2 in 100Nitrate 0.5 mg/L
- Hardeman CountyWell users 13,000Arsenic about 2 in 100Nitrate 0.4 mg/L
- Carroll CountyWell users 13,000Arsenic about 2 in 100Nitrate 0.4 mg/L
- Jefferson CountyWell users 12,900Arsenic about 3 in 100Nitrate 0.3 mg/L
- Lawrence CountyWell users 12,600Arsenic about 2 in 100Nitrate 1.8 mg/L
- Roane CountyWell users 12,400Arsenic about 2 in 100Nitrate 0.2 mg/L
- Rutherford CountyWell users 12,400Arsenic about 2 in 100Nitrate 0.7 mg/L
- Blount CountyWell users 12,300Arsenic about 2 in 100Nitrate 0.5 mg/L
- Grainger CountyWell users 12,200Arsenic about 2 in 100Nitrate 0.2 mg/L
- Rhea CountyWell users 12,200Arsenic about 2 in 100Nitrate 0.3 mg/L
- Claiborne CountyWell users 11,400Arsenic about 1 in 100Nitrate 0.2 mg/L
- Gibson CountyWell users 11,400Arsenic about 3 in 100Nitrate 0.4 mg/L
- Greene CountyWell users 10,900Arsenic about 3 in 100Nitrate 0.6 mg/L
- Washington CountyWell users 9,900Arsenic about 1 in 100Nitrate 0.7 mg/L
- Dickson CountyWell users 9,700Arsenic about 1 in 100Nitrate 0.4 mg/L
- Sumner CountyWell users 9,600Arsenic about 2 in 100Nitrate 1.3 mg/L
- Williamson CountyWell users 9,200Arsenic about 1 in 100Nitrate 0.4 mg/L
- Tipton CountyWell users 8,500Arsenic about 4 in 100Nitrate 1.1 mg/L
- Wilson CountyWell users 8,500Arsenic about 4 in 100Nitrate 0.5 mg/L
- Hamilton CountyWell users 8,400Arsenic about 2 in 100Nitrate 0.4 mg/L
- Bledsoe CountyWell users 8,100Arsenic about 2 in 100Nitrate 0.4 mg/L
- Chester CountyWell users 8,000Arsenic about 3 in 100Nitrate 0.4 mg/L
- Union CountyWell users 8,000Arsenic about 2 in 100Nitrate 0.1 mg/L
- Loudon CountyWell users 8,000Arsenic about 2 in 100Nitrate 0.6 mg/L
- Henderson CountyWell users 7,700Arsenic about 2 in 100Nitrate 0.4 mg/L
- Cumberland CountyWell users 7,700Arsenic about 3 in 100Nitrate 0.3 mg/L
- Benton CountyWell users 7,600Arsenic about 1 in 100Nitrate 0.2 mg/L
- Wayne CountyWell users 7,500Arsenic about 1 in 100Nitrate 0.3 mg/L
- Marshall CountyWell users 7,400Arsenic about 2 in 100Nitrate 0.7 mg/L
- Polk CountyWell users 7,200Arsenic about 3 in 100Nitrate 0.3 mg/L
- Humphreys CountyWell users 7,100Arsenic about 1 in 100Nitrate 0.2 mg/L
- Meigs CountyWell users 7,000Arsenic about 2 in 100Nitrate 0.2 mg/L
- Sullivan CountyWell users 7,000Arsenic about 2 in 100Nitrate 0.3 mg/L
- Haywood CountyWell users 6,800Arsenic about 3 in 100Nitrate 0.2 mg/L
- Cannon CountyWell users 6,800Arsenic about 3 in 100Nitrate 0.7 mg/L
- Bedford CountyWell users 6,700Arsenic about 2 in 100Nitrate 1.0 mg/L
- Marion CountyWell users 6,500Arsenic about 2 in 100Nitrate 0.2 mg/L
- Lincoln CountyWell users 6,300Arsenic about 2 in 100Nitrate 1.6 mg/L
- Campbell CountyWell users 6,200Arsenic about 1 in 100Nitrate 0.1 mg/L
- Giles CountyWell users 6,100Arsenic about 3 in 100Nitrate 0.5 mg/L
- Franklin CountyWell users 6,100Arsenic about 2 in 100Nitrate 2.2 mg/L
- Anderson CountyWell users 6,100Arsenic about 3 in 100Nitrate 0.2 mg/L
- Morgan CountyWell users 6,000Arsenic about 2 in 100Nitrate 0.1 mg/L
- Cheatham CountyWell users 6,000Arsenic about 2 in 100Nitrate 0.3 mg/L
- Stewart CountyWell users 5,700Arsenic about 1 in 100Nitrate 0.1 mg/L
- Fentress CountyWell users 5,500Arsenic about 3 in 100Nitrate 0.3 mg/L
- Hamblen CountyWell users 5,300Arsenic about 3 in 100Nitrate 0.5 mg/L
- Maury CountyWell users 5,200Arsenic about 2 in 100Nitrate 0.6 mg/L
- Hardin CountyWell users 5,100Arsenic about 2 in 100Nitrate 0.2 mg/L
- Hickman CountyWell users 5,100Arsenic about 1 in 100Nitrate 0.3 mg/L
- Macon CountyWell users 5,100Arsenic about 2 in 100Nitrate 0.8 mg/L
- Sequatchie CountyWell users 5,000Arsenic about 2 in 100Nitrate 0.2 mg/L
- Overton CountyWell users 4,800Arsenic about 2 in 100Nitrate 1.1 mg/L
- Scott CountyWell users 4,700Arsenic about 1 in 100Nitrate 0.1 mg/L
- McNairy CountyWell users 4,700Arsenic about 1 in 100Nitrate 0.2 mg/L
- Warren CountyWell users 4,700Arsenic about 2 in 100Nitrate 2.0 mg/L
- Carter CountyWell users 4,100Arsenic about 2 in 100Nitrate 0.2 mg/L
- Smith CountyWell users 3,800Arsenic about 3 in 100Nitrate 0.4 mg/L
- Lewis CountyWell users 3,700Arsenic about 1 in 100Nitrate 0.2 mg/L
- Johnson CountyWell users 3,600Arsenic about 3 in 100Nitrate 0.1 mg/L
- Obion CountyWell users 3,600Arsenic about 4 in 100Nitrate 0.2 mg/L
- DeKalb CountyWell users 3,500Arsenic about 3 in 100Nitrate 0.7 mg/L
- Davidson CountyWell users 3,100Arsenic about 2 in 100Nitrate 0.5 mg/L
- Perry CountyWell users 3,000Arsenic about 1 in 100Nitrate 0.1 mg/L
- Robertson CountyWell users 3,000Arsenic about 2 in 100Nitrate 2.6 mg/L
- Grundy CountyWell users 2,800Arsenic about 3 in 100Nitrate 0.4 mg/L
- Shelby CountyWell users 2,800Arsenic about 4 in 100Nitrate 0.4 mg/L
- Hancock CountyWell users 2,800Arsenic about 2 in 100Nitrate 0.1 mg/L
- Decatur CountyWell users 2,700Arsenic about 2 in 100Nitrate 0.4 mg/L
- White CountyWell users 2,600Arsenic about 2 in 100Nitrate 2.6 mg/L
- Montgomery CountyWell users 2,400Arsenic about 1 in 100Nitrate 1.2 mg/L
- Putnam CountyWell users 2,200Arsenic about 2 in 100Nitrate 1.4 mg/L
- Jackson CountyWell users 2,100Arsenic about 2 in 100Nitrate 0.4 mg/L
- Dyer CountyWell users 2,000Arsenic about 3 in 100Nitrate 0.1 mg/L
- Crockett CountyWell users 1,800Arsenic about 3 in 100Nitrate 0.1 mg/L
- Houston CountyWell users 1,600Arsenic about 1 in 100Nitrate 0.3 mg/L
- Clay CountyWell users 1,600Arsenic about 2 in 100Nitrate 0.7 mg/L
- Moore CountyWell users 1,600Arsenic about 2 in 100Nitrate 0.5 mg/L
- Lauderdale CountyWell users 1,300Arsenic about 4 in 100Nitrate 0.7 mg/L
- Unicoi CountyWell users 1,200Arsenic about 2 in 100Nitrate 0.1 mg/L
- Trousdale CountyWell users 910Arsenic about 2 in 100Nitrate 0.5 mg/L
- Pickett CountyWell users 600Arsenic about 2 in 100Nitrate 0.5 mg/L
- Van Buren CountyWell users 560Arsenic about 5 in 100Nitrate 0.3 mg/L
- Lake CountyWell users 480Arsenic about 3 in 100Nitrate 0.1 mg/L
Each mark = 1 in 100 well users the model places above 10 µg/L arsenic (scale 0–10)10 mg/L nitrate: the federal limit (MCL) for public systems
- These figures describe the area, not your well. Only a lab test shows what’s in your water.
- CDC says the Well Water Index figures “do not describe risk to individual wells.” (CDC Tracking Network)
- The arsenic model is better at spotting low-arsenic areas than at confirming high ones.
- Well-user counts are 2010 USGS estimates; tract values are averages over each census tract.
- Total coliform bacteriaEvery year
- NitrateEvery year
- Total dissolved solidsEvery year
- pHEvery year
- ArsenicAsk your local health department
EPA: Private Drinking Water Wells · CDC: Guidelines for Testing Well Water
Use a state-certified lab
Tennessee Department of Environment and Conservation lists the laboratories certified to test drinking water in Tennessee.
Screening tells you if something is worth a closer look
A lab result is the number you can act on.
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Lab-certified results
ETR Labs Basic Water Quality Test Kit
ETR Laboratories
50+ substances, including lead, copper, arsenic, nitrate, hardness and coliform bacteria
- Analyzed by Environmental Testing and Research Laboratories (ETR Labs), Leominster, MA · ISO/IEC 17025:2017, ANAB certificate AT-2638
- Turnaround: 2–4 business days after the lab receives it
What it can't tell you: It does not test PFAS, and not every result on the panel falls under the lab's accredited scope.
Screening: quick check, not lab-grade
Watersafe Drinking Water Test Kit
Silver Lake Research
Lead, bacteria, nitrate, copper, iron, chlorine, hardness and pH
- Turnaround: Minutes; the bacteria test can take up to 48 hours
What it can't tell you: Each test gives a yes/no or a rough range, not a lab number, and it cannot detect PFAS or arsenic.
A mail-in kit’s lab is accredited (ISO/IEC 17025) but may not be certified by your state. For a home sale, a loan, or a health-department follow-up, use a state-certified lab.
Tennessee well water
Sources: CDC Well Water Index (2024) · USGS arsenic and nitrate models · USGS domestic well populations · EPA and CDC testing guidance. Data last updated 2026-10-08. All sources →
How many people use private wells in Tennessee?
About 698,000 people across 95 Tennessee counties, by the USGS 2010 estimate. USGS models place about 17,000 of them in areas where wells are likely to be above the 10 µg/L arsenic limit. These are area estimates, not well results.
Are private wells regulated in Tennessee?
The quality and safety of drinking water from private domestic wells are not regulated by the Federal Government under the Safe Drinking Water Act nor by most state governments and laws. (EPA) Testing and treatment are the owner's responsibility.
Where can I get my well tested in Tennessee?
Tennessee Department of Environment and Conservation keeps the list of laboratories certified to test drinking water in Tennessee. Only use laboratories that are certified to do drinking water testing. (EPA)