Hard Water Map

Florida Water Hardness by County

Water in Florida has a median hardness of 151 mg/L as CaCO₃ — "hard" on the USGS scale — based on 150,764 measurements at 15,636 monitoring stations. Sarasota County has the state's hardest measured water (381 mg/L); Liberty County the softest (11.9). Rank: #19 of the 50 states and D.C.

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

Of Florida's 67 measured counties, 19 very hard, 15 hard, 13 moderately hard, and 20 soft. The hardest are Sarasota County (381 mg/L), Charlotte County (378), and Lee County (288). Liberty County is the softest at 11.9 mg/L (soft).

About 72% of Florida's roughly 21.9 million residents in counties with gate-passing hardness data live where tap water is hard or worse.

Statewide, Florida's median works out to 8.8 grains per gallon and ranks #19 of the 50 states and D.C. Across 150,764 measurements at 15,636 stations — 88,721 of them since 2000 — the middle 80% of readings fall between 29 and 390 mg/L. The public record runs from 1901 to 2025.

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

Download the Florida water hardness map (PNG) — Water hardness by county in Florida: 67 counties mapped from USGS/EPA data, statewide median 151 mg/L (hard); darker counties have harder water.

By county

Water hardness by county

The table lists all 67 measured Florida counties, hardest first. Their medians span 381 mg/L in Sarasota County to 11.9 in Liberty County — a 32× range.

County water hardness, hardest first — median mg/L as CaCO₃.
CountyMedianBandResultsSitesNewest
Sarasota County381Very hard2,4827982017
Charlotte County378Very hard2811182019
Lee County288Very hard12,4665542019
St. Lucie County280Very hard1,0262552019
Collier County273Very hard5,4685162019
Duval County267Very hard6,1153102017
Broward County250Very hard3,7225252020
Pinellas County250Very hard2,4576512016
Hendry County243Very hard3722362019
Miami-Dade County230Very hard7,4481,1112023
Nassau County219.5Very hard635512024
St. Johns County209Very hard4,0831202019
Levy County207Very hard659872017
Lafayette County200.3Very hard268572017
Monroe County200Very hard408942008
Palm Beach County200Very hard6,8249642019
Gilchrist County190Very hard277532017
Martin County190Very hard1,0703332019
Putnam County183Very hard5,5621652017
Indian River County177Hard6,5091412021
Brevard County175Hard9,5282712019
Dixie County160.4Hard137462017
Volusia County152Hard3,7301722017
Hillsborough County150Hard5,7491,0312017
Suwannee County148Hard9341382017
Taylor County147.6Hard550542017
Citrus County143Hard6321282017
Manatee County143Hard1,1473542020
DeSoto County140Hard1,0351842017
Glades County140Hard1,0521272017
Sumter County140Hard340982017
Hernando County139Hard6471632017
Lake County135.9Hard5,2814042017
Marion County132Hard3,0952202017
Seminole County111Moderately hard3,8952102017
Hardee County110Moderately hard3731222017
Pasco County110Moderately hard1,4892842023
Jefferson County94.7Moderately hard114362017
Calhoun County89Moderately hard326172017
Columbia County82.3Moderately hard5971142017
Hamilton County74.4Moderately hard470902017
Flagler County73.4Moderately hard967392019
Madison County70.1Moderately hard270652017
Polk County69.7Moderately hard3,7448672019
Orange County68Moderately hard14,1558572023
Wakulla County66.1Moderately hard9891222023
Okeechobee County61Moderately hard866992019
Jackson County54Soft4631002025
Osceola County51.8Soft2,8311902023
Clay County49.7Soft3,8601252017
Gulf County46.2Soft76312016
Franklin County45.5Soft304252023
Alachua County44.5Soft4,0411572017
Bay County44Soft4571082017
Highlands County34Soft6781872019
Holmes County30.8Soft248192017
Gadsden County29.5Soft7311082017
Leon County29Soft2,0582462017
Washington County28.1Soft196722017
Union County20Soft189342017
Okaloosa County18.9Soft7241192025
Walton County18Soft5241062024
Santa Rosa County17Soft969782025
Bradford County16.9Soft247472017
Escambia County15.6Soft1,1263672025
Baker County13Soft528342019
Liberty County11.9Soft270322017

ZIP codes

ZIP codes in Florida

The ZIP codes below are grouped by the Florida 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.

Sarasota County · 381 mg/L · Very hard

342233422834229342313423234233342343423534236†34237342383423934240†34241†3424234275†342853428634287342883428934291†34292†34293†

Charlotte County · 378 mg/L · Very hard

3394633947339483395033952339533395433955339803398133982†3398334224

Lee County · 288 mg/L · Very hard

33901339033390433905†339073390833909†3391233913†339143391633917†3391933920†33921339223392433928†33931†3395633957339653396633967†33971†33972†33973†33974†33976†3399033991†33993†3413434135

St. Lucie County · 280 mg/L · Very hard

34945†34946†3494734949†3495034951†3495234953349813498234983349843498634987†

Collier County · 273 mg/L · Very hard

34101†341023410334104341053410834109341103411234113†34114†3411634117†3411934120†34137†34138†341393414034141†34142†34145†

Duval County · 267 mg/L · Very hard

3220232203322043220532206322073220832209322103221132212322143221632217322183221932220†322213222232223322243222532226†32227322283223332234†322443224632250322543225632257322583226632277

Broward County · 250 mg/L · Very hard

33004330093301933020330213302233023†330243302533026330273302833029330603306233063330643306533066330673306833069330713307333076†333013330433305333063330833309333113331233313333143331533316333173331933321333223332333324333253332633327†3332833330†33331†33332†3333433351333883344133442

Pinellas County · 250 mg/L · Very hard

337013370233703337043370533706337073370833709337103371133712337133371433715†337163374433755337563375933760337613376233763337643376533767337703377133772337733377433776337773377833781337823378533786†346773468134683346843468534688346893469534698

Hendry County · 243 mg/L · Very hard

33440†33930†3393533936†

Miami-Dade County · 230 mg/L · Very hard

33010330123301333014330153301633018†33030†33031†3303233033†33034†33035†33039†3305433055330563310133109331223312533126†331273312833129331303313133132†3313333134331353313633137†3313833139331403314133142331433314433145331463314733149†331503315433155331563315733158331603316133162331653316633167331683316933170†33172331733317433175331763317733178†33179331803318133182331833318433185†3318633187†3318933190†33193†33194†33196†

Nassau County · 219.5 mg/L · Very hard

32009†32011†32034†3204632097†

St. Johns County · 209 mg/L · Very hard

32033†320803208132082†32084320863209232095†32145†32259

Levy County · 207 mg/L · Very hard

32621†32625†32626†32639†32668†32683†32696†34449†34498

Lafayette County · 200.3 mg/L · Very hard

32008†32013†32066†

Monroe County · 200 mg/L · Very hard

33001†33036†33037†33040†33042†33043†33050†33051†33070†

Palm Beach County · 200 mg/L · Very hard

3340133403334043340533406334073340833409334103341133412†3341333414334153341733418†334263342833430†33431334323343333434334353343633437334443344533446†33449†3345833460334613346233463†3346733470†3347233473†33476†3347733478†334803348333484334863348733493†3349633498

Gilchrist County · 190 mg/L · Very hard

32619†32693†

Martin County · 190 mg/L · Very hard

33438†334553346934956†34957†34990†349943499634997†

Putnam County · 183 mg/L · Very hard

32112†32131†32139†32140†32147†3214832157†32177†32181†32187†32189†3219332666†

Indian River County · 177 mg/L · Hard

32948†3295832960329623296332966†329673296832970

Brevard County · 175 mg/L · Hard

32754†32775†32780†32796328993290132903†32904†32905329073290832909†32920†32922329253292632927329313293432935329373294032949†32950†32951†3295232953329553295932976†

Dixie County · 160.4 mg/L · Hard

32359†32628†32648†32680†32692†

Volusia County · 152 mg/L · Hard

321143211732118321193212432127321283212932130†3213232141†321683216932174†321763218032190†32713327203272332724†32725327383274432759†3276332764†

Hillsborough County · 150 mg/L · Hard

33503335103351133527†335303353433547†33548†33549†33550335563355833559†3356333565†3356633567†3356933570335723357333578335793358433592†335943359633598†3360233603336043360533606†3360733609336103361133612336133361433615336163361733618336193362033621†3362433625336263362933634336353363733647

Suwannee County · 148 mg/L · Hard

32060†32062†32064†32071†32094†

Taylor County · 147.6 mg/L · Hard

32336†32347†32348†32356†

Citrus County · 143 mg/L · Hard

34428†3442934433†34434†3443634442†34445†344463444834450†34452†34453†34461†3446534487

Manatee County · 143 mg/L · Hard

342013420234203342053420734208†3420934210342113421234215342163421734219†34221†34222342433425034251†

DeSoto County · 140 mg/L · Hard

34266†34267†34268†34269†

Glades County · 140 mg/L · Hard

33471†33944†34974†

Sumter County · 140 mg/L · Hard

321623216333513†33514†3352133538†3358533597†34484†34785†

Hernando County · 139 mg/L · Hard

3460134602†34604†3460634607†346083460934613†3461434661†

Lake County · 135.9 mg/L · Hard

3210232159†32702†327263273532736†32757†32767†32776†3277834705†34711†34714†347153472934731†34736347373474834753347563476234788†34797†

Marion County · 132 mg/L · Hard

32113†32133†32134†32179†32182†32192†32195†32617†32634†3266432681†32686†32784†3442034431†34432†344703447134472†344733447434475†3447634479†34480†34481†34482†34488†34491

Seminole County · 111 mg/L · Moderately hard

327013270732708327143273032732†32746327503276532766†32771327733277932792

Hardee County · 110 mg/L · Moderately hard

33834†33865†33873†33890†

Pasco County · 110 mg/L · Moderately hard

33523†33525†33540335413354233543†33544335453357433576†34610†34637†34638†34639†3465234653†3465434655346673466834669†34679†3469034691

Jefferson County · 94.7 mg/L · Moderately hard

3233732344†32361

Calhoun County · 89 mg/L · Moderately hard

32421†32424†32430†32449†

Columbia County · 82.3 mg/L · Moderately hard

32024†32025†32038†32055†32061†32096†

Hamilton County · 74.4 mg/L · Moderately hard

32052†32053†

Flagler County · 73.4 mg/L · Moderately hard

32110†32136†3213732164

Madison County · 70.1 mg/L · Moderately hard

32059†32331†3234032350†

Polk County · 69.7 mg/L · Moderately hard

33801338033380533809†33810†338113381233813338153382333827†3383033835†33837†3383833839338403384133843338443384733849†3385033851338533385433855†3385633858†3385933860†33867†33868†33877†33880338813388433897†33898†34759

Orange County · 68 mg/L · Moderately hard

327033270932712327513276832789327983280132803328043280532806328073280832809328103281132812328143281632817328183281932820328213282232824328253282632827328283282932830328313283232833328353283632837328393473434760347613478634787

Wakulla County · 66.1 mg/L · Moderately hard

3232732346†3235532358†

Okeechobee County · 61 mg/L · Moderately hard

34972†

Jackson County · 54 mg/L · Soft

32420†32423†32426†32431†32432†32440†32442†32443†32445†32446†32448†32460†

Osceola County · 51.8 mg/L · Soft

3384833896†3473934741347433474434746347473475834769347713477234773

Clay County · 49.7 mg/L · Soft

32003320433206532068†320733207932656†

Gulf County · 46.2 mg/L · Soft

3245632465†

Franklin County · 45.5 mg/L · Soft

32320†32322†32323†32328†

Alachua County · 44.5 mg/L · Soft

326013260332605326063260732608†32609†326103261232615†326163261832631†32640†32641†32643†32653†32658†32667†32669†32694†

Bay County · 44 mg/L · Soft

32401†32403†32404†3240532407†3240832409†3241032413†32438†3244432466†

Highlands County · 34 mg/L · Soft

33825†3385233857†33870†33872†33875†33876†33960†

Holmes County · 30.8 mg/L · Soft

32425†32464†

Gadsden County · 29.5 mg/L · Soft

32324†32330†32332†32333†32343†3235132352†

Leon County · 29 mg/L · Soft

323013230332304†32305†32306323073230832309†32310†32311†323123231332317†32399†

Washington County · 28.1 mg/L · Soft

32427†32428†32437†32462†32463

Union County · 20 mg/L · Soft

32054†32083†32697†

Okaloosa County · 18.9 mg/L · Soft

32531†32536†325393254132542†32544†325473254832567†32569†32578†3257932580†

Walton County · 18 mg/L · Soft

32433†324353243932455†32459†32461†32550†

Santa Rosa County · 17 mg/L · Soft

32530†32563†32564†32565†3256632570†32571†32583

Bradford County · 16.9 mg/L · Soft

32026†32044†32058†32091†32622†

Escambia County · 15.6 mg/L · Soft

32501325023250332504325053250632507†32508†32509†32511325123251432526†325333253432535†32561†32568†32577†

Baker County · 13 mg/L · Soft

32040†3206332072†32087†

Liberty County · 11.9 mg/L · Soft

32321†32334†32360

† 395 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

Florida's groundwater measures harder than its surface water — 260 mg/L across 23,914 samples versus 136 across 125,249, about 1.9× harder. Wells draw from groundwater, so well owners in Florida tend to see the harder number — 260 mg/L, very hard. Groundwater readings there run 69.2 to 580 mg/L across the middle 80% of samples. The comparison draws on 7,431 groundwater and 7,998 surface-water monitoring sites; 6,106 readings above 2,000 mg/L were logged but held out of the medians as outliers.

Groundwater (wells)

260 mg/L as CaCO₃ · 23,914 results at 7,431 stations.

Surface water (rivers, lakes)

136 mg/L as CaCO₃ · 125,249 results at 7,998 stations.

Groundwater measures about 1.9× harder than surface water here.

Chemistry

Water chemistry in Florida

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

TDS

191 mg/L · n=41,736

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

pH

7.3 pH · n=79,253

pH 7.3 — within the EPA secondary range of 6.5–8.5, on the alkaline side.

Alkalinity

63.2 mg/L as CaCO3 · n=95,910

63.2 mg/L — modest buffering capacity.

Calcium : Magnesium

42 : 7.8 mg/L ≈ 5.38 : 1 · n=124,509

Calcium is about 77% of Florida's hardness (42 mg/L Ca to 7.8 mg/L Mg), a little more calcium-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 Florida

3 aquifer systems supply much of Florida's measured groundwater.

  • Intermediate aquifer system — median 370 mg/L across 1,432 samples at 653 sites: very hard.
  • Biscayne aquifer — median 267 mg/L across 1,301 samples at 483 sites: very hard.
  • Floridan aquifer system — median 250 mg/L across 8,915 samples at 2,165 sites: very hard.

Together these systems account for 11,648 measured samples at 3,301 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

1920s2020s270

Florida's decade median moved from 230 mg/L in the 1920s to 86.9 in the 2020s. Over the series, the decade median peaked at 270 mg/L in the 1930s and bottomed at 86.9 in the 2020s. Decade medians reflect where and what agencies sampled in each era, not just changes in the water itself.

Scale

Where Florida sits on the scale

On the USGS scale, Florida's 151 mg/L is hard — 8.8 grains per gallon, above the 120 mg/L hard cutoff, below very hard.

SoftModerately hardHardVery hard60 · 3.5 gpg120 · 7.0 gpg180 · 10.5 gpg151 mg/L — Hard
Harder than 52% of the 2,977 measured county medians.

At 151 mg/L (8.8 gpg), water-softener owners in Florida typically set their unit to this hardness — settings calculator.

Questions

Frequently asked questions

Is Florida's water hard?
Florida's median hardness is 151 mg/L as CaCO₃, "hard" on the USGS scale and 1.08× the national county median of 140 mg/L. About 72% of residents in measured counties have hard-or-worse water.
Which county in Florida has the hardest water?
Sarasota County, with a median of 381 mg/L as CaCO₃ across 2,482 measurements.
Is well water harder than city water in Florida?
Groundwater measures harder here — about 1.9× the surface water — so wells tend to run harder (groundwater 260 vs surface water 136 mg/L).
How do I find my exact hardness in Florida?
Search your ZIP on the lookup tool, read your utility's Consumer Confidence Report, or test at home with a kit.
Is Florida's water harder than the national average?
Yes. Florida's median of 151 mg/L is 1.08× the national county median of 140 mg/L, and Florida ranks #19 of the 50 states and D.C.

Compare

States with similar hardness

Two states measure closest to Florida's 151 mg/L: California at 150 mg/L and Nevada at 150 mg/L. Florida measures harder than 64% 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 — 150,764 Florida measurements. Data last verified . Methodology.

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