Hard Water Map

South Carolina Water Hardness by County

Water in South Carolina has a median hardness of 19 mg/L as CaCO₃ — "soft" on the USGS scale — based on 32,742 measurements at 3,601 monitoring stations. Beaufort County has the state's hardest measured water (116 mg/L); Aiken County the softest (4.5). Rank: #50 of the 50 states and D.C.

South Carolina water hardness map — what the numbers mean. Data verified 2026-07-22.

Of South Carolina's 46 measured counties, 2 moderately hard and 44 soft. The hardest are Beaufort County (116 mg/L), Charleston County (83.9), and Lancaster County (40.5). Aiken County is the softest at 4.5 mg/L (soft).

No measured South Carolina county reaches the hard threshold, so effectively none of its residents in counties with gate-passing hardness data live in a hard-or-worse county.

Statewide, South Carolina's median works out to 1.1 grains per gallon and ranks #50 of the 50 states and D.C. Across 32,742 measurements at 3,601 stations — 20,214 of them since 2000 — the middle 80% of readings fall between 6.3 and 53 mg/L. The public record runs from 1941 to 2026.

See where South Carolina sits nationally on the national map, or what its number means on the hardness scale.

Download the South Carolina water hardness map (PNG) — Water hardness by county in South Carolina: 46 counties mapped from USGS/EPA data, statewide median 19 mg/L (soft); darker counties have harder water.

By county

Water hardness by county

The table lists all 46 measured South Carolina counties, hardest first. Their medians span 116 mg/L in Beaufort County to 4.5 in Aiken County — a 25.8× range.

County water hardness, hardest first — median mg/L as CaCO₃.
CountyMedianBandResultsSitesNewest
Beaufort County116Moderately hard4631862025
Charleston County83.9Moderately hard5961472024
Lancaster County40.5Soft774652025
Bamberg County39.5Soft282472026
Chester County32Soft519742026
York County29.4Soft1,0461192025
Hampton County29Soft327492025
Allendale County28Soft177402026
Edgefield County27Soft201212026
Fairfield County26Soft487632026
Horry County26Soft7721582026
Newberry County26Soft860642026
Orangeburg County25.9Soft1,7871482026
Union County25Soft196372025
Georgetown County24Soft406952026
Sumter County23Soft1,712752026
Colleton County22Soft432752025
Cherokee County21Soft543562026
Darlington County21Soft216582025
Dorchester County21Soft731442025
Barnwell County20Soft2591682025
Saluda County20Soft347302026
Clarendon County19.6Soft3,392472025
Calhoun County19Soft1,171252025
Greenwood County19Soft174272026
Laurens County19Soft574752026
Berkeley County18.7Soft3,1951142025
Jasper County18Soft212392025
Williamsburg County17.4Soft378372026
Marion County17Soft420212026
Florence County16.9Soft705722026
McCormick County16Soft477612026
Richland County15.1Soft1,3221462026
Lexington County15Soft6961322025
Spartanburg County15Soft1,0881422026
Kershaw County14Soft461572025
Anderson County13Soft7751222026
Greenville County13Soft6881392026
Abbeville County12Soft326552025
Dillon County12Soft178292026
Chesterfield County9.4Soft413572025
Marlboro County9.4Soft114312025
Pickens County8.6Soft393652026
Lee County5Soft282202024
Oconee County4.6Soft1,3341012026
Aiken County4.5Soft8411682026

ZIP codes

ZIP codes in South Carolina

The ZIP codes below are grouped by the South Carolina county they fall in. Each ZIP takes its county's measured median — shown in the group header — so this is a ZIP-to-county guide, not a separate reading for every ZIP. To check the water system serving a specific address, use the lookup.

Beaufort County · 116 mg/L · Moderately hard

2990229904†29905†2990629907†299092991029915†29920†29926299282993529940†29941†

Charleston County · 83.9 mg/L · Moderately hard

294012940329404†29405294062940729409294122941429418†294242942529426†29429†29438†29439†2944929451†294552945629458†294642946629470†2948229487†

Lancaster County · 40.5 mg/L · Soft

29058†29067†29707†29720†

Bamberg County · 39.5 mg/L · Soft

29003†29042†29081†29843

Chester County · 32 mg/L · Soft

29031†29055†2970629712†29714†29724†29729†

York County · 29.4 mg/L · Soft

297042970829710297152971729726297302973229733297422974329745

Hampton County · 29 mg/L · Soft

29911†29916†2991829921†29922†29923†2992429939†29944†

Allendale County · 28 mg/L · Soft

29810†2982729836†29849†29932†

Edgefield County · 27 mg/L · Soft

29821†29824†29832†29838†29847†29860†

Fairfield County · 26 mg/L · Soft

29014†29015†2906529130†29180

Horry County · 26 mg/L · Soft

29511†29526†29527†29544†29545†29566†29568†29569†2957229575295762957729579†29581†2958229588†

Newberry County · 26 mg/L · Soft

29037†29075†2910829122†29126†29127†29145†29178†29355†

Orangeburg County · 25.9 mg/L · Soft

29018†29038290392904729048†2905929107†29112†29113†29115291172911829133†29142†29146†29163†29432†

Union County · 25 mg/L · Soft

29321†293532936429379†

Georgetown County · 24 mg/L · Soft

29440†29554†29585†

Sumter County · 23 mg/L · Soft

29040†29062†29125†29128†291502915229153†29154†29168†

Colleton County · 22 mg/L · Soft

29082†29435†29446†29452†29474†29475†29481†2948829493†29929†29945†

Cherokee County · 21 mg/L · Soft

29330†29340†29341†2937229702†

Darlington County · 21 mg/L · Soft

29069290792953229540†2955029593

Dorchester County · 21 mg/L · Soft

29420†29437†29448†29471†29472†29477†2948329485†

Barnwell County · 20 mg/L · Soft

29812†2981729826†29853

Saluda County · 20 mg/L · Soft

29006†29138†29166†

Clarendon County · 19.6 mg/L · Soft

29001†29051†29102†29111†29148†29162†

Calhoun County · 19 mg/L · Soft

29030†29135†

Greenwood County · 19 mg/L · Soft

29646†2964929653†29666†29819†

Laurens County · 19 mg/L · Soft

29325†29332†29351†2936029370†2938429645†29692†

Berkeley County · 18.7 mg/L · Soft

294102943129434†29436†29445†29450†29453†29461†29468†29469†29479†29486†29492

Jasper County · 18 mg/L · Soft

29912†29927†29934†29936†29943†

Williamsburg County · 17.4 mg/L · Soft

29056†29510†29518†29556†29564†29580†29590†

Marion County · 17 mg/L · Soft

29519†29546†29571†29574†29589†29592†

Florence County · 16.9 mg/L · Soft

29114†29161†2950129505†2950629530†2954129555†29560†2958329591†

McCormick County · 16 mg/L · Soft

2983529840†29844†29845†29848†29899†

Richland County · 15.1 mg/L · Soft

29016†29044†29052†29061†2906329177292012920329204292052920629207292082920929210292232922529229

Lexington County · 15 mg/L · Soft

29033290362905329054†2907029072†29073†29123†29160†29169291702917229212

Spartanburg County · 15 mg/L · Soft

2930129302293032930629307293162932029322†29323293242932929331293332933429335293382934629349†293652936829369†29373293742937529376293772937829385†29388

Kershaw County · 14 mg/L · Soft

29009†29020†29032†29045†29074†29078†29175†

Anderson County · 13 mg/L · Soft

2962129624†2962529626†296272964229654†29670†29684†29689†29697†

Greenville County · 13 mg/L · Soft

29356†29601296052960729609296112961329614296152961729635†29644296502965129661†29662296692967329680296812968329687†29690†

Abbeville County · 12 mg/L · Soft

29620†29628†29638†29639†29655†29659†

Dillon County · 12 mg/L · Soft

2953629543†29547†29563†29565†29567†

Chesterfield County · 9.4 mg/L · Soft

29101†29520†29584†29709†29718†29727†2972829741†

Marlboro County · 9.4 mg/L · Soft

29512†29516†29525†29570†29594†29596†

Pickens County · 8.6 mg/L · Soft

29630296312963429640†296572966729671†29682†29685†

Lee County · 5 mg/L · Soft

29010†29046†29080†29104†

Oconee County · 4.6 mg/L · Soft

29643†29658†29664†2966529672†29676†2967829686†2969129693†29696†

Aiken County · 4.5 mg/L · Soft

29105†29129†29137†29164†2980129803†29805†29809298162982829829†29831†2983429841†298422985129856†

† 258 ZIP codes are not served by a mapped community water system — most are private-well areas. See well water hardness.

Check any ZIP's utility and hardness →

Source

Groundwater vs surface water

South Carolina's groundwater measures harder than its surface water — 26 mg/L across 2,843 samples versus 18.8 across 29,471, about 1.4× harder. Wells draw from groundwater, so well owners in South Carolina tend to see the harder number — 26 mg/L, soft. Groundwater readings there run 4 to 157 mg/L across the middle 80% of samples. The comparison draws on 1,375 groundwater and 2,221 surface-water monitoring sites; 302 readings above 2,000 mg/L were logged but held out of the medians as outliers.

Groundwater (wells)

26 mg/L as CaCO₃ · 2,843 results at 1,375 stations.

Surface water (rivers, lakes)

18.8 mg/L as CaCO₃ · 29,471 results at 2,221 stations.

Groundwater measures about 1.4× harder than surface water here.

Chemistry

Water chemistry in South Carolina

Beyond the hardness number, South Carolina's water carries a fuller chemical signature — here is how its measured parameters compare to national benchmarks.

TDS

53 mg/L · n=813

53 mg/L — below the national county median of 226.

pH

6.9 pH · n=45,635

pH 6.9 — within the EPA secondary range of 6.5–8.5, on the acidic side.

Alkalinity

24 mg/L as CaCO3 · n=85,077

24 mg/L — modest buffering capacity.

Calcium : Magnesium

4.8 : 1.8 mg/L ≈ 2.67 : 1 · n=18,917

Calcium is about 62% of South Carolina's hardness (4.8 mg/L Ca to 1.8 mg/L Mg), a little more magnesium-rich than the national ~68% calcium share.

Parameter medians may include a small share of quality-control samples; the hardness lane is fully QC-filtered.

Aquifers

Major aquifers under South Carolina

3 aquifer systems supply much of South Carolina's measured groundwater.

  • Floridan aquifer system — median 90.7 mg/L across 829 samples at 351 sites: moderately hard.
  • Surficial aquifer system — median 51.2 mg/L across 284 samples at 150 sites: soft.
  • Piedmont and Blue Ridge crystalline-rock aquifers — median 48.4 mg/L across 59 samples at 56 sites: soft.

Together these systems account for 1,172 measured samples at 557 sites. Aquifer medians pool samples across a whole system and can mask local variation — see the national aquifer map for how these compare across states.

Trend

Hardness over time

1940s2020s24

South Carolina's decade median moved from 24 mg/L in the 1940s to 21 in the 2020s. Over the series, the decade median peaked at 24 mg/L in the 1940s and bottomed at 14 in the 1950s. Decade medians reflect where and what agencies sampled in each era, not just changes in the water itself.

Scale

Where South Carolina sits on the scale

On the USGS scale, South Carolina's 19 mg/L is soft — 1.1 grains per gallon, below the 60 mg/L soft cutoff — among the softest water measured in the US.

SoftModerately hardHardVery hard60 · 3.5 gpg120 · 7.0 gpg180 · 10.5 gpg19 mg/L — Soft
Harder than 8% of the 2,977 measured county medians.

Questions

Frequently asked questions

Is South Carolina's water hard?
South Carolina's median hardness is 19 mg/L as CaCO₃, "soft" on the USGS scale and below the national county median of 140 mg/L.
Which county in South Carolina has the hardest water?
Beaufort County, with a median of 116 mg/L as CaCO₃ across 463 measurements.
Is well water harder than city water in South Carolina?
Groundwater measures harder here — about 1.4× the surface water — so wells tend to run harder (groundwater 26 vs surface water 18.8 mg/L).
How do I find my exact hardness in South Carolina?
Search your ZIP on the lookup tool, read your utility's Consumer Confidence Report, or test at home with a kit.
Is South Carolina's water harder than the national average?
No. South Carolina's median of 19 mg/L is below the national county median of 140 mg/L; it ranks #50 of the 50 states and D.C.

Compare

States with similar hardness

Two states measure closest to South Carolina's 19 mg/L: Rhode Island at 20.2 mg/L and Mississippi at 21.1 mg/L. South Carolina measures harder than 2% of states. Browse the full ranking on the statistics page.

More: hardness scale · check your address · national statistics · the national map.

By . Source: USGS/EPA Water Quality Portal — 32,742 South Carolina measurements. Data last verified . Methodology.

Cite this page: “South Carolina Water Hardness by County.” Hard Water Map. Retrieved 2026-07-22, https://hardwatermap.com/water-hardness/south-carolina/