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Water Hardness in Tennessee

Across 27 measured cities — with 263 more covered by labeled county-level estimates — Tennessee's median tap water hardness is 74.1 mg/L (4.3 gpg): moderately hard on the USGS scale. Below: every covered city, the state's hardest and softest water, and the geology that explains it.

Data updated September 13, 2026. Sources: utility-reported water quality data and USGS/EPA Water Quality Portal samples.

State Median
74.1
mg/L (4.3 gpg), measured cities
Measured Range
18.2-138.0
mg/L across measured cities
Measured Cities
27
utility-reported or computed values
County Estimates
263
91% of covered cities

What it costs to soften Tennessee water

Water softener cost in Tennessee at 4.3 gpg prices the equipment and the installation labour against the plumber wages published for Tennessee, and labels every range as modelled or measured rather than leaving you to guess which it is.

Tennessee · 4.33 grains per gallon

$940–$1,193

installed, midpoint $1,053 — a 24,000-grain unit, the size 4 people at this hardness need.

Salt and drain water over 10 years: $566–$1,182 — the 4,741,350 grains of hardness this household removes, at the national salt price and water rate whose sources are named below. Filter changes and Service contract are omitted rather than assumed.

Sized for 4 people regenerating every 7 days: 9,093 grains of capacity needed, rounded up to the next common residential size. The median of 27 measured Tennessee cities in our hardness dataset. Modelled: the standard build band published for that state at the size this hardness calls for, equipment priced 2026-10-04 against the May 2025 reference period (OEWS M2025). Salt: the median retailer price of 3 retailers, read 2026-10-04, at a declared salt dose per regeneration. Drain water: about 50 gallons per regeneration from a government extension estimate read 2026-10-04, at the 2024 national average water and sewer rate from a government source read 2026-10-04.

Deciding whether it is worth it at all? Start from how much a water softener costs nationally — the same equipment, installation and ten-year ownership breakdown before any state wage adjustment is applied.

Tennessee Cities by Hardness Category

Measured cities only — labeled county estimates never enter the category counts or the median.

CategoryRangeMeasured citiesShare
Soft0-60 mg/L622.2%
Moderately hard60-120 mg/L1866.7%
Hard120-180 mg/L311.1%
Very hard>180 mg/L00.0%

Hardest and Softest Water in Tennessee

Measured values only; labeled county estimates and values under active dispute never rank.

Hardest water in Tennessee

  1. Spring Hill — 138.0 mg/L (8.1 gpg), hard
  2. Oak Ridge — 132.0 mg/L (7.7 gpg), hard
  3. Columbia — 127.0 mg/L (7.4 gpg), hard
  4. Franklin — 106.0 mg/L (6.2 gpg), moderately hard
  5. Kingsport — 106.0 mg/L (6.2 gpg), moderately hard

Softest water in Tennessee

  1. Grandview — 18.2 mg/L (1.1 gpg), soft
  2. Bartlett — 36.1 mg/L (2.1 gpg), soft
  3. Memphis — 40.2 mg/L (2.4 gpg), soft
  4. Maryville — 45.9 mg/L (2.7 gpg), soft
  5. Cookeville — 57.1 mg/L (3.3 gpg), soft

Every Covered City in Tennessee

All 290 covered Tennessee cities, sorted by population served. "County estimate" rows are labeled context values from USGS/EPA Water Quality Portal county sampling — they never enter the median above. City names link to each city's full water quality page.

CityHardness (mg/L)gpgCategoryData
Nashville89.45.2Moderately hardUtility-reported
Memphis40.22.4SoftUtility-reported
Knoxville83.64.9Moderately hardUtility-reported
Clarksville70.84.1Moderately hardUtility-reported
Chattanooga70.14.1Moderately hardUtility-reported
Murfreesboro90.35.3Moderately hardUtility-reported
Kingsport106.06.2Moderately hardUtility-reported
Johnson City59.53.5SoftUtility-reported
White House199.511.7Very hardCounty estimate
Jackson19.01.1SoftCounty estimate
Cleveland150.08.8HardCounty estimate
Morristown260.015.2Very hardCounty estimate
Mount Juliet84.44.9Moderately hardUtility-reported
Columbia127.07.4HardUtility-reported
Madison93.25.5Moderately hardUtility-reported
Franklin106.06.2Moderately hardUtility-reported
Hixson84.04.9Moderately hardCounty estimate
Dickson155.09.1HardCounty estimate
Smyrna200.011.7Very hardCounty estimate
Hendersonville90.95.3Moderately hardUtility-reported
Spring Hill138.08.1HardUtility-reported
Shelbyville130.07.6HardCounty estimate
Crossville33.01.9SoftCounty estimate
Bartlett36.12.1SoftUtility-reported
Gallatin77.14.5Moderately hardUtility-reported
Maryville45.92.7SoftUtility-reported
Collierville51.03.0SoftCounty estimate
Cookeville57.13.3SoftUtility-reported
Clinton143.08.4HardCounty estimate
Lebanon77.54.5Moderately hardUtility-reported
Seymour52.03.0SoftCounty estimate
Springfield199.511.7Very hardCounty estimate
Fayetteville160.09.4HardCounty estimate
La Vergne200.011.7Very hardCounty estimate
Germantown63.03.7Moderately hardUtility-reported
Bristol233.013.6Very hardCounty estimate
Sevierville52.03.0SoftCounty estimate
Oak Ridge132.07.7HardUtility-reported
Lewisburg206.012.1Very hardCounty estimate
Elizabethton39.72.3SoftCounty estimate
Millington51.03.0SoftCounty estimate
Lenoir City113.06.6Moderately hardCounty estimate
Jonesborough247.014.4Very hardCounty estimate
Dandridge257.015.0Very hardCounty estimate
Nolensville61.73.6Moderately hardUtility-reported
Sparta110.06.4Moderately hardCounty estimate
Brentwood74.14.3Moderately hardUtility-reported
Alcoa12.50.7SoftCounty estimate
Rockford12.50.7SoftCounty estimate
Kingston79.64.7Moderately hardCounty estimate
Tullahoma80.94.7Moderately hardCounty estimate
Lawrenceburg78.04.6Moderately hardCounty estimate
Winchester93.45.5Moderately hardCounty estimate
Munford56.03.3SoftCounty estimate
Jefferson City257.015.0Very hardCounty estimate
Atoka56.03.3SoftCounty estimate
Beersheba Springs59.43.5SoftCounty estimate
Dyersburg38.02.2SoftCounty estimate
La Follette105.06.1Moderately hardCounty estimate
Harriman79.64.7Moderately hardCounty estimate
Georgetown84.04.9Moderately hardCounty estimate
Corryton128.57.5HardCounty estimate
Mascot128.57.5HardCounty estimate
Athens160.09.4HardCounty estimate
Rogersville137.08.0HardCounty estimate
Smithville85.05.0Moderately hardCounty estimate
Dayton68.04.0Moderately hardCounty estimate
Graysville74.04.3Moderately hardCounty estimate
Covington56.03.3SoftCounty estimate
Hartsville254.014.8Very hardCounty estimate
Portland104.06.1Moderately hardCounty estimate
Rockwood79.64.7Moderately hardCounty estimate
Church Hill137.08.0HardCounty estimate
Mount Carmel137.08.0HardCounty estimate
Selmer21.01.2SoftCounty estimate
Russellville260.015.2Very hardCounty estimate
Lafayette110.06.4Moderately hardCounty estimate
Ocoee19.01.1SoftCounty estimate
Savannah23.01.4SoftCounty estimate
Livingston140.08.2HardCounty estimate
McMinnville120.07.0Moderately hardCounty estimate
Talbott257.015.0Very hardCounty estimate
Pleasant View199.511.7Very hardCounty estimate
Morrison120.07.0Moderately hardCounty estimate
Union City33.72.0SoftCounty estimate
Ripley135.07.9HardCounty estimate
Grimsley89.05.2Moderately hardCounty estimate
New Tazewell220.012.9Very hardCounty estimate
Blountville233.013.6Very hardCounty estimate
Loudon113.06.6Moderately hardCounty estimate
Madisonville74.04.3Moderately hardCounty estimate
Trenton19.01.1SoftCounty estimate
Pigeon Forge52.03.0SoftCounty estimate
Oakland17.01.0SoftCounty estimate
Pulaski133.07.8HardCounty estimate
Sweetwater74.04.3Moderately hardCounty estimate
Bethpage104.06.1Moderately hardCounty estimate
Vonore74.04.3Moderately hardCounty estimate
Greeneville252.014.7Very hardCounty estimate
Brownsville26.01.5SoftCounty estimate
Carthage88.05.2Moderately hardCounty estimate
Paris29.01.7SoftCounty estimate
Tennessee Ridge157.09.2HardCounty estimate
Lyles56.63.3SoftCounty estimate
Erwin19.01.1SoftCounty estimate
Etowah160.09.4HardCounty estimate
Woodlawn156.09.1HardCounty estimate
Townsend12.50.7SoftCounty estimate
Huntsville59.73.5SoftCounty estimate
Cumberland Gap220.012.9Very hardCounty estimate
Wartburg21.01.2SoftCounty estimate
Parsons27.01.6SoftCounty estimate
Mosheim252.014.7Very hardCounty estimate
Manchester80.94.7Moderately hardCounty estimate
Alamo36.02.1SoftCounty estimate
Jacksboro105.06.1Moderately hardCounty estimate
Woodbury141.08.3HardCounty estimate
Centerville56.63.3SoftCounty estimate
Milan19.01.1SoftCounty estimate
Prospect133.07.8HardCounty estimate
Hohenwald29.61.7SoftCounty estimate
Oneida59.73.5SoftCounty estimate
Decherd93.45.5Moderately hardCounty estimate
Estill Springs93.45.5Moderately hardCounty estimate
Gainesboro96.05.6Moderately hardCounty estimate
Mountain City47.02.8SoftCounty estimate
Martin19.01.1SoftCounty estimate
Luttrell170.09.9HardCounty estimate
Humboldt19.01.1SoftCounty estimate
Mount Pleasant186.010.9Very hardCounty estimate
Harrogate220.012.9Very hardCounty estimate
Adamsville21.01.2SoftCounty estimate
Jasper80.34.7Moderately hardCounty estimate
Mohawk252.014.7Very hardCounty estimate
Bean Station130.07.6HardCounty estimate
Altamont59.43.5SoftCounty estimate
Palmer59.43.5SoftCounty estimate
Henderson13.70.8SoftCounty estimate
Bluff City233.013.6Very hardCounty estimate
Rickman140.08.2HardCounty estimate
Greenbrier199.511.7Very hardCounty estimate
Erin157.09.2HardCounty estimate
Newbern38.02.2SoftCounty estimate
Ashland City140.08.2HardCounty estimate
Gatlinburg52.03.0SoftCounty estimate
Dunlap104.56.1Moderately hardCounty estimate
Monterey147.08.6HardCounty estimate
Byrdstown100.05.8Moderately hardCounty estimate
Fairmount68.84.0Moderately hardUtility-reported
Signal Mountain68.84.0Moderately hardUtility-reported
Maynardville170.09.9HardCounty estimate
Lynnville133.07.8HardCounty estimate
South Pittsburg80.34.7Moderately hardCounty estimate
Minor Hill133.07.8HardCounty estimate
Linden35.92.1SoftCounty estimate
Counce23.01.4SoftCounty estimate
Whitwell69.54.1Moderately hardUtility-reported
Baxter147.08.6HardCounty estimate
Lynchburg126.57.4HardCounty estimate
Decatur98.55.8Moderately hardCounty estimate
Huntingdon18.41.1SoftCounty estimate
Tellico Plains74.04.3Moderately hardCounty estimate
Red Boiling Springs110.06.4Moderately hardCounty estimate
Sale Creek84.04.9Moderately hardCounty estimate
Leoma78.04.6Moderately hardCounty estimate
Dover119.07.0Moderately hardCounty estimate
New Market257.015.0Very hardCounty estimate
Spencer31.81.9SoftCounty estimate
Spring City68.04.0Moderately hardCounty estimate
Celina93.95.5Moderately hardCounty estimate
Friendsville12.50.7SoftCounty estimate
Tracy City59.43.5SoftCounty estimate
Adams199.511.7Very hardCounty estimate
Summertown78.04.6Moderately hardCounty estimate
Oliver Springs21.01.2SoftCounty estimate
Westmoreland104.06.1Moderately hardCounty estimate
Springville29.01.7SoftCounty estimate
Jellico105.06.1Moderately hardCounty estimate
Somerville17.01.0SoftCounty estimate
Pleasant Hill33.01.9SoftCounty estimate
Gordonsville88.05.2Moderately hardCounty estimate
Hornbeak33.72.0SoftCounty estimate
Loretto78.04.6Moderately hardCounty estimate
Allons140.08.2HardCounty estimate
Waynesboro42.82.5SoftCounty estimate
Cedar Grove18.41.1SoftCounty estimate
Scotts Hill27.01.6SoftCounty estimate
Unicoi19.01.1SoftCounty estimate
Lobelville35.92.1SoftCounty estimate
Only56.63.3SoftCounty estimate
Moss93.95.5Moderately hardCounty estimate
Sewanee93.45.5Moderately hardCounty estimate
Brighton56.03.3SoftCounty estimate
Camden21.01.2SoftCounty estimate
White Pine257.015.0Very hardCounty estimate
Hampton39.72.3SoftCounty estimate
South Fulton33.72.0SoftCounty estimate
Allardt89.05.2Moderately hardCounty estimate
Englewood160.09.4HardCounty estimate
Riceville160.09.4HardCounty estimate
Jamestown89.05.2Moderately hardCounty estimate
Monteagle80.34.7Moderately hardCounty estimate
Mason17.01.0SoftCounty estimate
Elkton133.07.8HardCounty estimate
Niota160.09.4HardCounty estimate
Vanleer155.09.1HardCounty estimate
Dresden19.01.1SoftCounty estimate
Holladay21.01.2SoftCounty estimate
Tiptonville99.05.8Moderately hardCounty estimate
Calhoun160.09.4HardCounty estimate
Dyer19.01.1SoftCounty estimate
Michie21.01.2SoftCounty estimate
Alexandria85.05.0Moderately hardCounty estimate
Ducktown19.01.1SoftCounty estimate
Turtletown19.01.1SoftCounty estimate
Cowan93.45.5Moderately hardCounty estimate
Surgoinsville137.08.0HardCounty estimate
New Johnsonville101.55.9Moderately hardCounty estimate
Bells26.01.5SoftCounty estimate
Benton19.01.1SoftCounty estimate
Greenfield19.01.1SoftCounty estimate
Bell Buckle130.07.6HardCounty estimate
Chapel Hill206.012.1Very hardCounty estimate
Decaturville27.01.6SoftCounty estimate
Sneedville173.510.2HardCounty estimate
Ramer21.01.2SoftCounty estimate
Norris143.08.4HardCounty estimate
Rutledge130.07.6HardCounty estimate
Riddleton88.05.2Moderately hardCounty estimate
Saltillo23.01.4SoftCounty estimate
Halls135.07.9HardCounty estimate
Troy33.72.0SoftCounty estimate
Ridgely99.05.8Moderately hardCounty estimate
Grandview18.21.1SoftUtility-reported
Watertown170.09.9HardCounty estimate
Collinwood42.82.5SoftCounty estimate
Big Sandy21.01.2SoftCounty estimate
Clifton42.82.5SoftCounty estimate
Mooresburg137.08.0HardCounty estimate
Gleason19.01.1SoftCounty estimate
Bruceton18.41.1SoftCounty estimate
Belvidere93.45.5Moderately hardCounty estimate
Kenton19.01.1SoftCounty estimate
Obion33.72.0SoftCounty estimate
Huntland93.45.5Moderately hardCounty estimate
St. Joseph78.04.6Moderately hardCounty estimate
Rutherford19.01.1SoftCounty estimate
Whiteville20.81.2SoftCounty estimate
Sharon19.01.1SoftCounty estimate
Atwood18.41.1SoftCounty estimate
Rossville17.01.0SoftCounty estimate
Clairfield220.012.9Very hardCounty estimate
Bradford19.01.1SoftCounty estimate
Liberty85.05.0Moderately hardCounty estimate
Cumberland City119.07.0Moderately hardCounty estimate
Butler47.02.8SoftCounty estimate
Sardis15.00.9SoftCounty estimate
Maury City36.02.1SoftCounty estimate
Henning135.07.9HardCounty estimate
Roan Mountain39.72.3SoftCounty estimate
Trezevant18.41.1SoftCounty estimate
Petersburg160.09.4HardCounty estimate
Gallaway17.01.0SoftCounty estimate
Friendship36.02.1SoftCounty estimate
Bethel Springs21.01.2SoftCounty estimate
Hollow Rock18.41.1SoftCounty estimate
Hornsby20.81.2SoftCounty estimate
Moscow17.01.0SoftCounty estimate
Puryear29.01.7SoftCounty estimate
Trimble33.72.0SoftCounty estimate
Gates26.01.5SoftCounty estimate
Samburg33.72.0SoftCounty estimate
Stanton26.01.5SoftCounty estimate
Iron City42.82.5SoftCounty estimate
Henry29.01.7SoftCounty estimate
Gibson19.01.1SoftCounty estimate
Middleton20.81.2SoftCounty estimate
Westpoint78.04.6Moderately hardCounty estimate
Sharps Chapel170.09.9HardCounty estimate
Charleston150.08.8HardCounty estimate
Christiana200.011.7Very hardCounty estimate
Copperhill19.01.1SoftCounty estimate
Fall Branch247.014.4Very hardCounty estimate
Goodlettsville160.09.4HardCounty estimate
Harrison84.04.9Moderately hardCounty estimate
Lookout Mountain84.04.9Moderately hardCounty estimate
Louisville12.50.7SoftCounty estimate
Pegram140.08.2HardCounty estimate
Powell128.57.5HardCounty estimate
Rockvale200.011.7Very hardCounty estimate

Above 120 mg/L (7 gpg), scale is usually worth treating — see our water softener guide, or size a system with the hardness calculator & converter.

The Geology Behind Tennessee's Water Hardness

Tennessee sits in the Appalachian and Mid-Atlantic mixed terrain region.

The Mid-Atlantic and Appalachian states sit on a patchwork of sandstone, shale, and crystalline rock that yields mostly soft to moderately hard water. The big exception is the region's limestone and dolomite valleys - including the carbonate belt running from Pennsylvania down through the Shenandoah Valley - where groundwater dissolves calcium and magnesium readily and comes out distinctly hard. A city's number here depends heavily on whether its supply draws from upland rivers and reservoirs or from carbonate-valley wells.

Source: USGS - Principal Aquifers of the United States

Tennessee Water Hardness FAQ

Does Tennessee have hard water?

On the whole, no — Tennessee's statewide median sits below the hard threshold, though some cities run harder. The median is 74.1 mg/L (4.3 gpg) — moderately hard on the USGS scale, where anything above 120 mg/L (7 gpg) counts as hard. 3 of Tennessee's 27 measured cities fall in the hard or very hard bands (11%), so check your own city rather than the state average.

How hard is tap water in Tennessee?

Across the 27 Tennessee cities with measured values in our index, the median hardness is 74.1 mg/L (4.3 gpg) — moderately hard on the USGS scale. Individual cities range from 18.2 to 138.0 mg/L, so check your own city rather than assuming the state number.

Which city in Tennessee has the hardest water?

Spring Hill has the hardest measured tap water in our Tennessee index at 138.0 mg/L (8.1 gpg) — hard on the USGS scale. Rankings use measured utility values only; labeled county estimates and values under active dispute are excluded.

Do I need a water softener in Tennessee?

3 of Tennessee's 27 measured cities (11%) fall in the hard or very hard bands — above 120 mg/L (7 gpg), the level where most water treatment professionals suggest considering an ion-exchange softener. Hardness varies utility to utility, so look up your own city's value before sizing equipment.

How do I find my city's exact water hardness?

Enter your ZIP code in our free lookup at tapwaterdata.com/zip to see the value we hold for your Tennessee city from utility-reported water quality data, check your water utility's annual Consumer Confidence Report (CCR), or use a home test-strip kit.

Need whole-house or professional water treatment?

For the problems a pitcher or under-sink filter cannot fix — scale, rust and black staining, sulfur smell, well contamination, or test results you cannot explain. Tell us what is happening and we will connect you with a local water-treatment professional.

TapWaterData may be compensated when you are connected with a water-treatment professional.

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