Water Quality in Iowa
1,076 water systems • 593 cities • EPA SDWIS Data
1,076
Water Systems
9,389
Total Violations
934
Health-Based Violations
3,000,306
Population Served
Overview
Iowa has 1,076 active community water systems serving 3,000,306 people. These systems have accumulated 9,389 EPA Safe Drinking Water Act violations on record, of which 934 are health-based violations (meaning a contaminant exceeded safe levels).
Common contaminants found in violations: E. coli, Fecal Coliform, Contaminant 1009, Nitrate, Total Organic Carbon, Chlorine Dioxide, TTHM, Contaminant 1041, Selenium, Chlorine.
Cities with Most Violations in Iowa
| # | City | Violations | Health-Based | Water Systems | Population |
|---|---|---|---|---|---|
| 1 | Muscatine | 431 | 4 | 24 | 29,914 |
| 2 | Cedar Rapids | 426 | 7 | 15 | 143,238 |
| 3 | Oxford | 295 | 61 | 27 | 4,176 |
| 4 | Dubuque | 222 | 1 | 12 | 60,492 |
| 5 | Centerville | 196 | 0 | 5 | 60,024 |
| 6 | Walford | 164 | 8 | 4 | 591 |
| 7 | Fort Dodge | 154 | 73 | 19 | 29,432 |
| 8 | Plymouth | 136 | 0 | 1 | 378 |
| 9 | Marshalltown | 132 | 22 | 15 | 34,613 |
| 10 | Jesup | 131 | 0 | 3 | 3,389 |
Largest Cities in Iowa
| # | City | Population | Violations | Water Systems |
|---|---|---|---|---|
| 1 | Des Moines | 254,814 | 36 | 6 |
| 2 | Davenport | 149,541 | 37 | 13 |
| 3 | Cedar Rapids | 143,238 | 426 | 15 |
| 4 | Ames | 97,467 | 14 | 4 |
| 5 | Iowa City | 97,293 | 79 | 16 |
| 6 | Sioux City | 85,824 | 21 | 2 |
| 7 | Ankeny | 80,663 | 26 | 10 |
| 8 | Waterloo | 69,892 | 5 | 2 |
| 9 | West Des Moines | 68,748 | 0 | 2 |
| 10 | Newton | 66,010 | 70 | 24 |
All Cities in Iowa
| City | Population | Violations | Health Violations | Contaminants |
|---|---|---|---|---|
| Des Moines | 254,814 | 36 | 2 | Fecal Coliform |
| Davenport | 149,541 | 37 | 0 | |
| Cedar Rapids | 143,238 | 426 | 7 | Chlorine, Chlorine Dioxide, Contaminant 1041 +1 more |
| Ames | 97,467 | 14 | 0 | |
| Iowa City | 97,293 | 79 | 13 | Chlorine Dioxide, E. coli, TTHM +1 more |
| Sioux City | 85,824 | 21 | 10 | Contaminant 2257, TTHM |
| Ankeny | 80,663 | 26 | 0 | |
| Waterloo | 69,892 | 5 | 2 | Selenium |
| West Des Moines | 68,748 | 0 | 0 | |
| Newton | 66,010 | 70 | 0 | |
| Council Bluffs | 64,447 | 1 | 0 | |
| Dubuque | 60,492 | 222 | 1 | Chlorine Dioxide |
| Centerville | 60,024 | 196 | 0 | |
| Urbandale | 45,605 | 1 | 0 | |
| Ottumwa | 42,942 | 16 | 0 | |
| Marion | 42,861 | 1 | 1 | Total Organic Carbon |
| Cedar Falls | 40,951 | 9 | 0 | |
| Creston | 38,079 | 13 | 2 | Contaminant 2257 |
| Indianola | 35,928 | 4 | 0 | |
| Marshalltown | 34,613 | 132 | 22 | Selenium |
| Waukee | 31,823 | 1 | 0 | |
| Muscatine | 29,914 | 431 | 4 | Chlorine Dioxide, Selenium |
| Fort Dodge | 29,432 | 154 | 73 | Barium, Contaminant 1041, E. coli +1 more |
| Bouton | 29,382 | 39 | 5 | TTHM |
| Mason City | 27,338 | 8 | 0 | |
| Spencer | 27,098 | 2 | 0 | |
| Burlington | 26,205 | 3 | 2 | Fecal Coliform |
| Johnston | 25,233 | 36 | 0 | |
| Clinton | 25,019 | 1 | 0 | |
| Oskaloosa | 24,586 | 20 | 2 | E. coli |
| Coralville | 22,378 | 7 | 0 | |
| Tama | 21,540 | 8 | 0 | |
| North Liberty | 20,546 | 2 | 0 | |
| Altoona | 19,565 | 15 | 3 | HAA5 |
| Clive | 19,010 | 0 | 0 | |
| Grimes | 15,580 | 5 | 0 | |
| Knoxville | 15,173 | 7 | 0 | |
| Norwalk | 14,334 | 0 | 0 | |
| Grinnell | 13,192 | 102 | 36 | Disinfection Byproducts, E. coli, HAA5 +1 more |
| Storm Lake | 13,166 | 9 | 0 | |
| Boone | 12,704 | 8 | 7 | E. coli, Fecal Coliform |
| Clarinda | 12,253 | 9 | 1 | Selenium |
| Pella | 11,289 | 4 | 0 | |
| Fort Madison | 11,087 | 1 | 0 | |
| Lemars | 10,571 | 0 | 0 | |
| Waverly | 10,519 | 5 | 0 | |
| Fairfield | 10,289 | 9 | 0 | |
| Carroll | 10,184 | 1 | 0 | |
| Cherokee | 9,965 | 0 | 0 | |
| Keokuk | 9,900 | 0 | 0 | |
| Bondurant | 9,393 | 0 | 0 | |
| Denison | 9,381 | 0 | 0 | |
| Eldridge | 9,288 | 30 | 1 | Barium |
| Mount Pleasant | 9,274 | 3 | 0 | |
| May City | 9,114 | 2 | 0 | |
| Manning | 9,108 | 6 | 0 | |
| Decorah | 8,390 | 0 | 0 | |
| Sioux Center | 8,231 | 4 | 0 | |
| Washington | 8,187 | 20 | 0 | |
| Perry | 7,836 | 0 | 0 | |
| Webster City | 7,825 | 2 | 0 | |
| Clear Lake | 7,737 | 2 | 0 | |
| Rock Rapids | 7,698 | 7 | 0 | |
| Charles City | 7,446 | 10 | 0 | |
| Adel | 7,421 | 22 | 1 | Lead |
| Avoca | 7,387 | 11 | 3 | Chlorine Dioxide |
| Hiawatha | 7,255 | 12 | 0 | |
| Atlantic | 7,252 | 1 | 0 | |
| Maquoketa | 7,071 | 4 | 1 | Chlorine Dioxide |
| Nevada | 6,925 | 1 | 0 | |
| Polk City | 6,558 | 0 | 0 | |
| Glenwood | 6,307 | 5 | 0 | |
| Rock Valley | 6,289 | 10 | 3 | Chlorine Dioxide |
| Orange City | 6,267 | 1 | 0 | |
| Independence | 6,220 | 0 | 0 | |
| Spirit Lake | 6,167 | 3 | 3 | Fecal Coliform |
| Oelwein | 6,062 | 2 | 0 | |
| Ireton | 6,010 | 0 | 0 | |
| Asbury | 5,943 | 0 | 0 | |
| Estherville | 5,904 | 0 | 0 | |
| Dewitt | 5,792 | 14 | 0 | |
| Anamosa | 5,785 | 12 | 2 | |
| Red Oak | 5,596 | 13 | 0 | |
| Sheldon | 5,512 | 0 | 0 | |
| Osceola | 5,503 | 18 | 13 | Bromate, Contaminant 2257, Fecal Coliform |
| Algona | 5,487 | 1 | 0 | |
| Winterset | 5,428 | 2 | 2 | Bromate |
| Iowa Falls | 5,231 | 22 | 0 | |
| Shenandoah | 5,101 | 5 | 1 | TTHM |
| Vinton | 5,100 | 1 | 0 | |
| Manchester | 5,077 | 0 | 0 | |
| Harlan | 5,067 | 0 | 0 | |
| Sergeant Bluff | 5,015 | 1 | 0 | |
| Hampton | 4,921 | 4 | 0 | |
| Humboldt | 4,897 | 21 | 0 | |
| Camanche | 4,570 | 37 | 0 | |
| Evansdale | 4,561 | 5 | 0 | |
| Madrid | 4,530 | 27 | 9 | Chlorine, Contaminant 2257, Fecal Coliform |
| Mount Vernon | 4,527 | 1 | 0 | |
| Tiffin | 4,512 | 1 | 0 | |
| Dyersville | 4,477 | 21 | 16 | Total Organic Carbon |
| West Burlington | 4,440 | 3 | 0 | |
| Solon | 4,398 | 93 | 1 | Disinfection Byproducts |
| Chariton | 4,381 | 110 | 82 | Chlorine, E. coli, Fecal Coliform +1 more |
| Tipton | 4,294 | 86 | 23 | Barium |
| Forest City | 4,285 | 1 | 0 | |
| Huxley | 4,244 | 0 | 0 | |
| Jefferson | 4,182 | 3 | 0 | |
| Oxford | 4,176 | 295 | 61 | Barium, Chlorine Dioxide, E. coli +1 more |
| Carlisle | 4,170 | 10 | 0 | |
| Hospers | 4,146 | 12 | 2 | Chlorine Dioxide |
| Monticello | 4,121 | 2 | 0 | |
| Milford | 4,037 | 64 | 0 | |
| Panora | 3,991 | 11 | 0 | |
| Waukon | 3,982 | 9 | 0 | |
| Cresco | 3,913 | 0 | 0 | |
| West Liberty | 3,858 | 0 | 0 | |
| Carter Lake | 3,791 | 29 | 0 | |
| Emmetsburg | 3,733 | 5 | 0 | |
| Albia | 3,721 | 0 | 0 | |
| Osage | 3,637 | 1 | 0 | |
| Eagle Grove | 3,601 | 3 | 0 | |
| New Hampton | 3,494 | 4 | 0 | |
| Belle Plaine | 3,484 | 48 | 0 | |
| Jesup | 3,389 | 131 | 0 | |
| Sibley | 3,359 | 3 | 0 | |
| Story City | 3,357 | 8 | 0 | |
| Williamsburg | 3,345 | 5 | 0 | |
| Montezuma | 3,295 | 1 | 0 | |
| Epworth | 3,255 | 3 | 0 | |
| Manly | 3,213 | 53 | 0 | |
| Garner | 3,065 | 0 | 0 | |
| Missouri Valley | 2,939 | 82 | 1 | Chlorine Dioxide |
| Wilton | 2,924 | 0 | 0 | |
| Onawa | 2,906 | 0 | 0 | |
| Sigourney | 2,875 | 5 | 0 | |
| Belmond | 2,863 | 2 | 0 | |
| Kalona | 2,857 | 10 | 1 | Barium |
| Fairfax | 2,853 | 19 | 0 | |
| Clarion | 2,810 | 2 | 0 | |
| Grundy Center | 2,796 | 0 | 0 | |
| Peosta | 2,793 | 15 | 0 | |
| Hawarden | 2,700 | 4 | 0 | |
| Bloomfield | 2,682 | 2 | 0 | |
| Eldora | 2,664 | 0 | 0 | |
| Ogden | 2,659 | 2 | 0 | |
| Center Point | 2,579 | 0 | 0 | |
| Rockwell City | 2,550 | 10 | 2 | |
| Hudson | 2,546 | 0 | 0 | |
| West Union | 2,540 | 0 | 0 | |
| Mitchellville | 2,515 | 12 | 2 | Chlorine |
| Postville | 2,513 | 7 | 0 | |
| West Branch | 2,509 | 7 | 0 | |
| Marengo | 2,481 | 39 | 35 | Selenium |
| Denver | 2,467 | 24 | 0 | |
| Gladbrook | 2,461 | 8 | 0 | |
| Toledo | 2,399 | 17 | 6 | Total Organic Carbon |
| Cascade | 2,386 | 1 | 0 | |
| Whittemore | 2,386 | 61 | 7 | Barium |
| Hull | 2,384 | 0 | 0 | |
| Lake Mills | 2,366 | 1 | 0 | |
| Bellevue | 2,363 | 5 | 5 | Total Organic Carbon |
| Ely | 2,328 | 1 | 0 | |
| Colfax | 2,305 | 1 | 0 | |
| Lisbon | 2,293 | 8 | 0 | |
| Laporte City | 2,284 | 8 | 0 | |
| Greenfield | 2,227 | 6 | 2 | E. coli |
| Adair | 2,120 | 55 | 0 | |
| Lamoni | 2,104 | 30 | 6 | Fecal Coliform, TTHM |
| Wapello | 2,096 | 4 | 0 | |
| Alta | 2,087 | 0 | 0 | |
| Northwood | 2,072 | 1 | 0 | |
| Britt | 2,064 | 5 | 0 | |
| Sac City | 2,063 | 0 | 0 | |
| Mechanicsville | 2,059 | 18 | 0 | |
| Atkins | 2,056 | 8 | 3 | TTHM |
| Audubon | 2,053 | 0 | 0 | |
| Ida Grove | 2,051 | 0 | 0 | |
| Woodward | 2,046 | 21 | 5 | Barium, TTHM |
| Sumner | 2,030 | 0 | 0 | |
| Parkersburg | 2,019 | 0 | 0 | |
| Monroe | 2,007 | 0 | 0 | |
| Mount Ayr | 1,930 | 30 | 0 | |
| Traer | 1,927 | 6 | 0 | |
| Newell | 1,923 | 32 | 0 | |
| Van Horne | 1,919 | 23 | 2 | Contaminant 1041 |
| New London | 1,910 | 3 | 0 | |
| Pocahontas | 1,905 | 3 | 0 | |
| Dallas Center | 1,901 | 4 | 0 | |
| Durant | 1,871 | 0 | 0 | |
| Monona | 1,853 | 3 | 0 | |
| Leon | 1,830 | 33 | 22 | Fecal Coliform, TTHM, Total Haloacetic Acids (HAA5) |
| Columbus Junction | 1,830 | 6 | 0 | |
| Guttenberg | 1,817 | 0 | 0 | |
| Stuart | 1,814 | 0 | 0 | |
| Remsen | 1,770 | 6 | 0 | |
| Farley | 1,766 | 4 | 1 | Total Organic Carbon |
| Moville | 1,757 | 2 | 0 | |
| Leclaire | 1,742 | 59 | 0 | |
| Corning | 1,735 | 8 | 4 | Contaminant 1009, Fecal Coliform |
| Lake City | 1,731 | 8 | 0 | |
| Manson | 1,709 | 4 | 0 | |
| Prairie City | 1,703 | 0 | 0 | |
| Mediapolis | 1,688 | 0 | 0 | |
| Logan | 1,677 | 6 | 0 | |
| Pleasantville | 1,676 | 1 | 1 | HAA5 |
| Riceville | 1,654 | 25 | 0 | |
| Granger | 1,654 | 12 | 0 | |
| Batavia | 1,631 | 20 | 0 | |
| Woodbine | 1,622 | 6 | 0 | |
| Urbana | 1,619 | 45 | 0 | |
| Corydon | 1,610 | 8 | 0 | |
| Hartley | 1,605 | 0 | 0 | |
| State Center | 1,598 | 17 | 0 | |
| Guthrie Center | 1,593 | 0 | 0 | |
| Wyoming | 1,574 | 29 | 0 | |
| Akron | 1,558 | 2 | 0 | |
| Nashua | 1,551 | 18 | 0 | |
| Walcott | 1,551 | 5 | 0 | |
| Amana | 1,548 | 8 | 1 | Selenium |
| Slater | 1,548 | 10 | 3 | Contaminant 1041 |
| Oakland | 1,524 | 2 | 0 | |
| Wellman | 1,524 | 8 | 0 | |
| Bedford | 1,508 | 5 | 0 | |
| Brooklyn | 1,505 | 0 | 0 | |
| Holstein | 1,501 | 0 | 0 | |
| Earlham | 1,446 | 1 | 0 | |
| Palo | 1,407 | 8 | 0 | |
| Kingsley | 1,396 | 0 | 0 | |
| Roland | 1,394 | 0 | 0 | |
| Sanborn | 1,392 | 31 | 0 | |
| Lenox | 1,339 | 2 | 0 | |
| Dike | 1,306 | 2 | 0 | |
| Lowden | 1,304 | 11 | 0 | |
| Laurens | 1,301 | 4 | 0 | |
| Coon Rapids | 1,300 | 0 | 0 | |
| Dysart | 1,281 | 2 | 0 | |
| Shell Rock | 1,269 | 0 | 0 | |
| Central City | 1,264 | 1 | 0 | |
| Fayette | 1,256 | 1 | 0 | |
| Gilmore City | 1,249 | 26 | 2 | Selenium |
| Springville | 1,249 | 3 | 0 | |
| Alton | 1,248 | 1 | 0 | |
| Glidden | 1,232 | 8 | 0 | |
| Elkader | 1,219 | 1 | 0 | |
| Jewell | 1,216 | 6 | 0 | |
| Melcher Dallas | 1,213 | 2 | 0 | |
| Gilbert | 1,211 | 106 | 0 | |
| Colo | 1,206 | 14 | 0 | |
| Tripoli | 1,191 | 0 | 0 | |
| Tabor | 1,181 | 12 | 0 | |
| Blue Grass | 1,179 | 114 | 0 | |
| Buffalo | 1,176 | 4 | 0 | |
| Fredericksburg | 1,170 | 11 | 2 | Disinfection Byproducts |
| Lake Park | 1,167 | 0 | 0 | |
| St. Ansgar | 1,161 | 7 | 0 | |
| Strawberry Point | 1,155 | 0 | 0 | |
| Brighton | 1,142 | 22 | 0 | |
| Lake View | 1,133 | 17 | 2 | |
| Villisca | 1,132 | 3 | 0 | |
| Sheffield | 1,130 | 1 | 0 | |
| Aplington | 1,126 | 1 | 1 | Contaminant 1041 |
| Calmar | 1,125 | 0 | 0 | |
| Mapleton | 1,124 | 4 | 0 | |
| Fairbank | 1,111 | 6 | 5 | Total Organic Carbon |
| Arnolds Park | 1,110 | 0 | 0 | |
| Ossian | 1,110 | 5 | 0 | |
| Conrad | 1,098 | 0 | 0 | |
| Marcus | 1,079 | 3 | 0 | |
| Sidney | 1,077 | 9 | 0 | |
| George | 1,077 | 0 | 0 | |
| Van Meter | 1,074 | 1 | 0 | |
| Rockwell | 1,071 | 6 | 0 | |
| Elk Run Heights | 1,069 | 2 | 0 | |
| North English | 1,065 | 3 | 0 | |
| Riverside | 1,060 | 5 | 0 | |
| Treynor | 1,049 | 8 | 0 | |
| Malvern | 1,046 | 11 | 1 | Selenium |
| Sloan | 1,042 | 0 | 0 | |
| Dunlap | 1,035 | 6 | 0 | |
| Winfield | 1,035 | 1 | 0 | |
| Janesville | 1,034 | 0 | 0 | |
| Griswold | 1,008 | 8 | 0 | |
| Baxter | 1,002 | 15 | 0 | |
| Paullina | 996 | 12 | 0 | |
| Greene | 994 | 3 | 0 | |
| Odebolt | 994 | 0 | 0 | |
| Lansing | 983 | 1 | 1 | Total Organic Carbon |
| Long Grove | 976 | 3 | 0 | |
| Anita | 972 | 5 | 0 | |
| Aurelia | 968 | 0 | 0 | |
| Allison | 966 | 1 | 0 | |
| Wayland | 966 | 2 | 0 | |
| Shellsburg | 961 | 1 | 0 | |
| Keosauqua | 961 | 12 | 0 | |
| Gowrie | 954 | 0 | 0 | |
| Preston | 949 | 3 | 0 | |
| Lawton | 943 | 6 | 0 | |
| Edgewood | 939 | 2 | 0 | |
| Hinton | 935 | 7 | 0 | |
| Inwood | 928 | 1 | 0 | |
| Larchwood | 926 | 1 | 0 | |
| Princeton | 923 | 6 | 3 | Selenium |
| West Point | 921 | 6 | 0 | |
| Sioux Rapids | 920 | 8 | 0 | |
| Legrand | 910 | 1 | 0 | |
| Carson | 910 | 6 | 0 | |
| Keota | 897 | 3 | 0 | |
| Graettinger | 897 | 0 | 0 | |
| Primghar | 896 | 3 | 0 | |
| Hamburg | 890 | 12 | 0 | |
| Donnellson | 885 | 28 | 12 | HAA5, Total Organic Carbon |
| Sully | 881 | 1 | 0 | |
| Armstrong | 875 | 9 | 1 | Disinfection Byproducts |
| Hills | 863 | 2 | 0 | |
| Hubbard | 860 | 0 | 0 | |
| Maxwell | 859 | 7 | 0 | |
| Readlyn | 845 | 0 | 0 | |
| Dunkerton | 842 | 1 | 0 | |
| Winthrop | 840 | 1 | 0 | |
| Cambridge | 832 | 0 | 0 | |
| West Bend | 822 | 3 | 0 | |
| Calamus | 809 | 16 | 1 | Total Organic Carbon |
| Schleswig | 803 | 3 | 0 | |
| Gilbertville | 794 | 4 | 0 | |
| Okoboji | 793 | 2 | 0 | |
| Milo | 788 | 7 | 0 | |
| Wall Lake | 780 | 2 | 2 | Selenium |
| Ruthven | 779 | 0 | 0 | |
| Wheatland | 775 | 3 | 2 | Contaminant 1041 |
| Salem | 769 | 22 | 0 | |
| Dakota City | 769 | 0 | 0 | |
| Walnut | 768 | 0 | 0 | |
| Correctionville | 766 | 0 | 0 | |
| Melbourne | 765 | 0 | 0 | |
| Exira | 764 | 6 | 2 | Chlorine Dioxide |
| Garnavillo | 763 | 3 | 0 | |
| Alden | 763 | 1 | 0 | |
| Rockford | 762 | 0 | 0 | |
| Manilla | 758 | 5 | 0 | |
| Morning Sun | 752 | 0 | 0 | |
| Mcgregor | 747 | 3 | 0 | |
| Redfield | 744 | 0 | 0 | |
| Blairstown | 738 | 3 | 3 | Contaminant 1041 |
| Montrose | 738 | 4 | 1 | Fecal Coliform |
| Schaller | 729 | 3 | 2 | Chlorine Dioxide |
| Hedrick | 728 | 6 | 0 | |
| Whiting | 727 | 0 | 0 | |
| Shelby | 727 | 6 | 0 | |
| Grand Junction | 725 | 9 | 0 | |
| Earlville | 724 | 2 | 0 | |
| Essex | 722 | 2 | 0 | |
| Wellsburg | 721 | 0 | 0 | |
| Merrill | 717 | 25 | 0 | |
| Ventura | 716 | 2 | 0 | |
| Bancroft | 711 | 0 | 0 | |
| Stratford | 707 | 6 | 0 | |
| Phoenix | 702 | 0 | 0 | |
| Coggon | 701 | 52 | 0 | |
| Boyden | 701 | 1 | 0 | |
| Lakeside | 700 | 0 | 0 | |
| Battle Creek | 700 | 1 | 0 | |
| Dexter | 693 | 2 | 0 | |
| Ellsworth | 691 | 3 | 0 | |
| Walker | 688 | 1 | 0 | |
| Elgin | 685 | 1 | 0 | |
| Murray | 684 | 0 | 0 | |
| Alburnett | 675 | 5 | 0 | |
| Pomeroy | 671 | 11 | 1 | Contaminant 1041 |
| Fontanelle | 670 | 0 | 0 | |
| Kanawha | 658 | 0 | 0 | |
| Milton | 644 | 8 | 0 | |
| Moravia | 637 | 10 | 0 | |
| Stanwood | 637 | 0 | 0 | |
| Seymour | 637 | 0 | 0 | |
| Fonda | 636 | 5 | 0 | |
| Goldfield | 634 | 0 | 0 | |
| Elk Horn | 631 | 19 | 0 | |
| Sutherland | 629 | 2 | 0 | |
| Hopkinton | 622 | 1 | 0 | |
| Agency | 620 | 0 | 0 | |
| Doon | 619 | 6 | 0 | |
| Kellogg | 617 | 9 | 0 | |
| Grand Mound | 615 | 1 | 0 | |
| Spillville | 614 | 0 | 0 | |
| Allerton | 609 | 9 | 0 | |
| Moulton | 607 | 0 | 0 | |
| Farmington | 601 | 10 | 0 | |
| Keystone | 599 | 9 | 4 | Chlorine Dioxide, Contaminant 1041 |
| Neola | 598 | 13 | 0 | |
| Walford | 591 | 164 | 8 | Barium |
| Early | 587 | 11 | 11 | Selenium |
| Clermont | 586 | 3 | 0 | |
| South English | 586 | 15 | 0 | |
| Olds | 584 | 10 | 0 | |
| Swea City | 584 | 0 | 0 | |
| Everly | 575 | 1 | 0 | |
| Radcliffe | 561 | 2 | 0 | |
| Badger | 561 | 0 | 0 | |
| Leland | 553 | 20 | 3 | Contaminant 1041 |
| Anthon | 545 | 3 | 0 | |
| Zearing | 528 | 28 | 3 | Contaminant 2257, E. coli |
| Dows | 526 | 2 | 0 | |
| Arcadia | 525 | 3 | 0 | |
| Charter Oak | 522 | 4 | 0 | |
| Miles | 517 | 13 | 0 | |
| Titonka | 511 | 5 | 0 | |
| Ainsworth | 511 | 9 | 0 | |
| Delhi | 509 | 8 | 0 | |
| Rolfe | 509 | 2 | 0 | |
| Sabula | 506 | 27 | 0 | |
| Elma | 505 | 1 | 0 | |
| Collins | 505 | 0 | 0 | |
| Scranton | 504 | 19 | 0 | |
| Breda | 500 | 7 | 0 | |
| Thompson | 499 | 1 | 0 | |
| New Virginia | 498 | 1 | 0 | |
| Farragut | 490 | 0 | 0 | |
| Garwin | 481 | 0 | 0 | |
| Russell | 477 | 15 | 0 | |
| Maynard | 476 | 0 | 0 | |
| Lovilia | 472 | 0 | 0 | |
| Dow City | 467 | 10 | 2 | Selenium |
| Norway | 466 | 11 | 0 | |
| Stacyville | 465 | 4 | 0 | |
| Humeston | 462 | 27 | 0 | |
| Cascasde | 455 | 15 | 2 | Chlorine Dioxide |
| Klemme | 441 | 6 | 0 | |
| Little Rock | 441 | 1 | 1 | Disinfection Byproducts |
| Ocheyedan | 439 | 2 | 0 | |
| Hawkeye | 438 | 0 | 0 | |
| Grandview | 437 | 26 | 0 | |
| Ashton | 436 | 4 | 0 | |
| Galva | 435 | 1 | 0 | |
| Lost Nation | 434 | 40 | 0 | |
| New Albin | 432 | 1 | 0 | |
| Lamont | 429 | 3 | 0 | |
| Marquette | 429 | 3 | 3 | Total Organic Carbon |
| Oxford Junction | 424 | 5 | 0 | |
| Martensdale | 421 | 0 | 0 | |
| Arlington | 419 | 1 | 0 | |
| Burt | 418 | 0 | 0 | |
| Panama | 417 | 0 | 0 | |
| Emerson | 412 | 2 | 0 | |
| Lawler | 406 | 8 | 2 | Contaminant 1041 |
| Earling | 397 | 2 | 0 | |
| Plainfield | 393 | 0 | 0 | |
| Wesley | 390 | 0 | 0 | |
| Washinginton | 390 | 3 | 0 | |
| Casey | 387 | 0 | 0 | |
| Colesburg | 386 | 0 | 0 | |
| New Market | 385 | 5 | 3 | Total Haloacetic Acids (HAA5) |
| Duncombe | 384 | 0 | 0 | |
| Vail | 383 | 3 | 0 | |
| Livermore | 383 | 7 | 1 | Disinfection Byproducts |
| New Vienna | 382 | 4 | 0 | |
| Worthington | 382 | 1 | 0 | |
| Lynnville | 380 | 1 | 0 | |
| Plymouth | 378 | 136 | 0 | |
| Churdan | 375 | 7 | 0 | |
| Orient | 368 | 1 | 0 | |
| Birmingham | 367 | 6 | 0 | |
| Ringsted | 365 | 3 | 0 | |
| Massena | 364 | 41 | 6 | Barium, Chlorine Dioxide |
| Stanhope | 364 | 8 | 0 | |
| Lacona | 361 | 2 | 0 | |
| Rudd | 358 | 0 | 0 | |
| Lewis | 357 | 4 | 2 | Selenium |
| Holy Cross | 356 | 5 | 0 | |
| Templeton | 352 | 0 | 0 | |
| Ryan | 350 | 14 | 1 | Contaminant 1041 |
| Pleasant Hill | 350 | 10 | 0 | |
| Fort Atkinson | 347 | 0 | 0 | |
| Elliott | 345 | 12 | 0 | |
| Brandon | 341 | 6 | 0 | |
| Ute | 338 | 4 | 0 | |
| Diagonal | 338 | 30 | 0 | |
| Pierson | 337 | 2 | 0 | |
| Middletown | 336 | 6 | 0 | |
| Terril | 334 | 4 | 0 | |
| Mystic | 322 | 8 | 0 | |
| Peterson | 322 | 0 | 0 | |
| Danbury | 320 | 2 | 2 | Selenium |
| Williams | 315 | 8 | 0 | |
| Floyd | 313 | 4 | 1 | Endrin |
| Irwin | 313 | 12 | 0 | |
| Vincent | 311 | 8 | 0 | |
| Granville | 310 | 0 | 0 | |
| Sheldahl | 307 | 16 | 4 | Contaminant 1041 |
| Fertile | 306 | 31 | 0 | |
| Blakesburg | 305 | 4 | 0 | |
| Bode | 304 | 0 | 0 | |
| Kelley | 304 | 0 | 0 | |
| Luana | 301 | 3 | 0 | |
| Lester | 296 | 2 | 0 | |
| Salix | 295 | 1 | 0 | |
| Bronson | 294 | 3 | 0 | |
| Cincinnati | 290 | 3 | 0 | |
| Kimballton | 287 | 18 | 0 | |
| Alta Vista | 282 | 3 | 0 | |
| Lytton | 282 | 2 | 0 | |
| Westside | 277 | 10 | 0 | |
| Macedonia | 275 | 1 | 0 | |
| Ridgeway | 275 | 2 | 0 | |
| Marble Rock | 272 | 1 | 0 | |
| Rhodes | 271 | 1 | 0 | |
| Malcom | 270 | 0 | 0 | |
| Protivin | 269 | 2 | 0 | |
| Yale | 267 | 0 | 0 | |
| Cumberland | 266 | 0 | 0 | |
| Corwith | 266 | 3 | 0 | |
| Auburn | 265 | 2 | 0 | |
| Maurice | 265 | 0 | 0 | |
| Steamboat Rock | 264 | 111 | 0 | |
| Lu Verne | 258 | 6 | 0 | |
| Kiron | 257 | 3 | 0 | |
| Mallard | 257 | 65 | 52 | Barium |
| Kensett | 257 | 2 | 0 | |
| Hornick | 255 | 0 | 0 | |
| Fenton | 254 | 0 | 0 | |
| Deloit | 250 | 10 | 0 | |
| Riverton | 250 | 14 | 0 | |
| Defiance | 250 | 23 | 0 | |
| Lineville | 250 | 2 | 0 | |
| Quimby | 249 | 3 | 0 | |
| Deep River | 249 | 1 | 0 | |
| Luxemburg | 245 | 0 | 0 | |
| Pisgah | 245 | 0 | 0 | |
| Los Angeles | 245 | 11 | 0 | |
| Halbur | 243 | 1 | 0 | |
| Kansas City | 240 | 17 | 0 | |
| Goose Lake | 239 | 5 | 0 | |
| Boca Raton | 236 | 11 | 0 | |
| Harvey | 236 | 4 | 0 | |
| De Soto | 235 | 1 | 0 | |
| Renwick | 234 | 0 | 0 | |
| Marathon | 230 | 1 | 0 | |
| Chelsea | 229 | 17 | 0 | |
| Blencoe | 224 | 1 | 0 | |
| Cantril | 224 | 6 | 0 | |
| Dedham | 221 | 97 | 16 | Arsenic |
| Laurel | 220 | 0 | 0 | |
| Coulter | 219 | 8 | 0 | |
| Grafton | 218 | 0 | 0 | |
| Clutier | 213 | 1 | 0 | |
| Washta | 209 | 0 | 0 | |
| Wadena | 209 | 2 | 1 | Chlorine Dioxide |
| Alvord | 206 | 0 | 0 | |
| Hanlontown | 206 | 9 | 0 | |
| Volga | 203 | 2 | 0 | |
| Montour | 203 | 0 | 0 | |
| Swisher | 201 | 2 | 0 | |
| Oakville | 200 | 10 | 0 | |
| Hancock | 200 | 1 | 0 | |
| Jamaica | 195 | 47 | 5 | Contaminant 1041 |
| Westgate | 192 | 1 | 0 | |
| Stout | 191 | 4 | 0 | |
| Moorhead | 189 | 8 | 0 | |
| Woden | 188 | 20 | 0 | |
| Magnolia | 188 | 4 | 0 | |
| Smithland | 181 | 0 | 0 | |
| Soldier | 180 | 20 | 0 | |
| Pilot Mound | 176 | 0 | 0 | |
| Wallingford | 170 | 6 | 0 | |
| Lidderdale | 166 | 5 | 0 | |
| Little Sioux | 166 | 13 | 1 | Barium |
| Linn Grove | 163 | 7 | 0 | |
| Beaman | 161 | 2 | 0 | |
| Prairieburg | 160 | 1 | 0 | |
| Shambaugh | 159 | 1 | 1 | TTHM |
| Barnes City | 156 | 8 | 0 | |
| Randall | 154 | 0 | 0 | |
| Braddyville | 147 | 2 | 0 | |
| Bristow | 145 | 9 | 9 | Selenium |
| West Chester | 144 | 2 | 0 | |
| Woolstock | 144 | 2 | 0 | |
| Brayton | 143 | 3 | 0 | |
| Springbrook | 143 | 2 | 0 | |
| Goodell | 140 | 3 | 0 | |
| Clemons | 140 | 0 | 0 | |
| Palmer | 138 | 3 | 0 | |
| Geneva | 136 | 0 | 0 | |
| Ft Dodge | 136 | 0 | 0 | |
| Millersburg | 135 | 2 | 0 | |
| Superior | 132 | 3 | 0 | |
| Monmouth | 129 | 55 | 0 | |
| Somers | 128 | 4 | 0 | |
| Maharishi Vedic City | 128 | 43 | 0 | |
| Pacific Junction | 125 | 13 | 1 | Barium |
| Saint Charles | 121 | 3 | 0 | |
| Dawson | 116 | 20 | 0 | |
| Bernard | 114 | 0 | 0 | |
| Castana | 103 | 67 | 0 |
Data Sources
Drinking water data from the EPA Safe Drinking Water Information System (SDWIS). Only active community water systems (CWS) serving 100+ people are included.