Water Hardness in Iowa

99 counties — Average 342.8 PPM (Very Hard)

8
91
Soft (0.0%) Moderate (0.0%) Hard (8.1%) Very Hard (91.9%)

Iowa Water Hardness Map

Soft   Moderate   Hard   Very Hard

Hardest Water Counties

Adams280 PPM
Allamakee310 PPM
Appanoose220 PPM
Audubon380 PPM
Benton340 PPM
Black Hawk260 PPM
Boone360 PPM
Bremer240 PPM
Buchanan280 PPM
Buena Vista580 PPM
Butler240 PPM
Calhoun580 PPM
+79 more
Iowa

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All 99 Counties — By Water Hardness

CountyClassificationHardness
Adair Hard 180 PPM
Adams Very Hard 280 PPM
Allamakee Very Hard 310 PPM
Appanoose Very Hard 220 PPM
Audubon Very Hard 380 PPM
Benton Very Hard 340 PPM
Black Hawk Very Hard 260 PPM
Boone Very Hard 360 PPM
Bremer Very Hard 240 PPM
Buchanan Very Hard 280 PPM
Buena Vista Very Hard 580 PPM
Butler Very Hard 240 PPM
Calhoun Very Hard 580 PPM
Carroll Very Hard 360 PPM
Cass Very Hard 200 PPM
Cedar Very Hard 320 PPM
Cerro Gordo Very Hard 340 PPM
Cherokee Very Hard 520 PPM
Chickasaw Very Hard 250 PPM
Clarke Hard 160 PPM
Clay Very Hard 515 PPM
Clayton Very Hard 300 PPM
Clinton Very Hard 190 PPM
Crawford Very Hard 440 PPM
Dallas Very Hard 346.5 PPM
Davis Hard 140 PPM
Decatur Very Hard 257.5 PPM
Delaware Very Hard 260 PPM
Des Moines Very Hard 230 PPM
Dickinson Very Hard 220 PPM
Dubuque Very Hard 260 PPM
Emmet Very Hard 760 PPM
Fayette Very Hard 320 PPM
Floyd Very Hard 255 PPM
Franklin Very Hard 350 PPM
Fremont Very Hard 273 PPM
Greene Very Hard 410 PPM
Grundy Very Hard 360 PPM
Guthrie Very Hard 300 PPM
Hamilton Very Hard 360 PPM
Hancock Very Hard 370 PPM
Hardin Very Hard 351 PPM
Harrison Very Hard 400 PPM
Henry Very Hard 400 PPM
Howard Very Hard 270 PPM
Humboldt Very Hard 400 PPM
Ida Very Hard 420 PPM
Iowa Very Hard 320 PPM
Jackson Very Hard 310 PPM
Jasper Very Hard 360 PPM
Jefferson Very Hard 293 PPM
Johnson Very Hard 270 PPM
Jones Very Hard 310 PPM
Keokuk Very Hard 460 PPM
Kossuth Very Hard 440 PPM
Lee Very Hard 200 PPM
Linn Very Hard 260 PPM
Louisa Very Hard 238 PPM
Lucas Very Hard 250 PPM
Lyon Very Hard 440 PPM
Madison Very Hard 200 PPM
Mahaska Very Hard 340 PPM
Marion Very Hard 280 PPM
Marshall Very Hard 380 PPM
Mills Very Hard 345 PPM
Mitchell Very Hard 280.5 PPM
Monona Very Hard 420 PPM
Monroe Very Hard 290 PPM
Montgomery Very Hard 230 PPM
Muscatine Hard 180 PPM
O'Brien Very Hard 470 PPM
Osceola Very Hard 1300 PPM
Page Very Hard 240 PPM
Palo Alto Very Hard 695 PPM
Plymouth Very Hard 427.8 PPM
Pocahontas Very Hard 713.5 PPM
Polk Very Hard 303 PPM
Pottawattamie Very Hard 291.5 PPM
Poweshiek Very Hard 460 PPM
Ringgold Hard 170 PPM
Sac Very Hard 490 PPM
Scott Very Hard 200 PPM
Shelby Very Hard 410 PPM
Sioux Very Hard 490 PPM
Story Very Hard 370 PPM
Tama Very Hard 340 PPM
Taylor Hard 140 PPM
Union Hard 150 PPM
Van Buren Very Hard 283 PPM
Wapello Very Hard 272 PPM
Warren Very Hard 260 PPM
Washington Very Hard 400 PPM
Wayne Hard 140 PPM
Webster Very Hard 480 PPM
Winnebago Very Hard 370 PPM
Winneshiek Very Hard 307 PPM
Woodbury Very Hard 430 PPM
Worth Very Hard 323.5 PPM
Wright Very Hard 360 PPM

Source: USGS Water Quality Portal

Frequently Asked Questions

How hard is the water in Iowa?

Iowa has an average water hardness of 342.8 PPM, classified as very hard. Out of 99 counties, 0 have soft water, 0 moderately hard, 8 hard, and 91 very hard.

Which Iowa counties have the hardest water?

Iowa has 91 counties with very hard water (above 180 mg/L). See the county table above for a complete breakdown by hardness level.

How do I check water hardness for my Iowa address?

Enter your ZIP code in the search box above to see your area's estimated water hardness, classification, and water utility information.