Water Quality by County
3,254 counties with public water systems.
| County | State | Systems | Population | Violations |
|---|---|---|---|---|
| Los Angeles | California | 276 | 10,109,089 | 3,972 |
| Richmond | New York | 1 | 8,271,000 | 47 |
| Harris | Texas | 1,292 | 6,016,117 | 78,495 |
| Cook | Illinois | 427 | 5,304,996 | 21,728 |
| Maricopa | Arizona | 215 | 4,392,896 | 30,745 |
| San Diego | California | 197 | 3,744,323 | 4,832 |
| Suffolk | Massachusetts | 8 | 3,456,243 | 111 |
| Miami-Dade | Florida | 167 | 3,325,406 | 3,677 |
| Orange | California | 46 | 3,201,893 | 507 |
| King | Washington | 217 | 3,193,095 | 20,636 |
| Dallas | Texas | 37 | 3,180,170 | 2,618 |
| Riverside | California | 201 | 2,839,125 | 6,103 |
| San Bernardino | California | 318 | 2,830,626 | 4,611 |
| Clark | Nevada | 145 | 2,620,052 | 14,829 |
| Bexar | Texas | 82 | 2,376,579 | 13,955 |
| Alameda | California | 27 | 2,249,634 | 275 |
| Tarrant | Texas | 113 | 2,099,244 | 10,564 |
| Santa Clara | California | 119 | 2,097,044 | 2,640 |
| Allegheny | Pennsylvania | 69 | 2,014,752 | 5,241 |
| Montgomery | Maryland | 56 | 1,971,831 | 1,796 |
| Broward | Florida | 55 | 1,905,863 | 4,156 |
| Wayne | Michigan | 55 | 1,774,820 | 1,141 |
| Hillsborough | Florida | 724 | 1,701,663 | 27,775 |
| Sacramento | California | 166 | 1,685,812 | 2,206 |
| Fulton | Georgia | 11 | 1,636,505 | 332 |
| Middlesex | Massachusetts | 204 | 1,623,176 | 16,575 |
| Orange | Florida | 114 | 1,615,975 | 5,841 |
| Baltimore city | Maryland | 13 | 1,608,056 | 122 |
| Philadelphia | Pennsylvania | 6 | 1,601,175 | 447 |
| Travis | Texas | 138 | 1,547,700 | 7,557 |
| Palm Beach | Florida | 71 | 1,538,245 | 3,569 |
| Franklin | Ohio | 96 | 1,503,985 | 5,342 |
| Salt Lake | Utah | 77 | 1,463,023 | 13,678 |
| Cuyahoga | Ohio | 11 | 1,410,751 | 1,166 |
| Suffolk | New York | 152 | 1,387,905 | 3,402 |
| Nassau | New York | 44 | 1,387,489 | 7,471 |
| Fairfax | Virginia | 44 | 1,317,489 | 2,070 |
| Denver | Colorado | 5 | 1,312,794 | 487 |
| Montgomery | Pennsylvania | 172 | 1,274,688 | 36,032 |
| Hennepin | Minnesota | 202 | 1,273,140 | 1,534 |
| Collin | Texas | 35 | 1,246,210 | 1,149 |
| Mecklenburg | North Carolina | 61 | 1,181,269 | 8,081 |
| Pinellas | Florida | 13 | 1,147,926 | 410 |
| Oakland | Michigan | 742 | 1,147,613 | 21,952 |
| St. Louis | Missouri | 23 | 1,145,619 | 1,825 |
| Wake | North Carolina | 437 | 1,145,508 | 42,422 |
| Pima | Arizona | 195 | 1,138,545 | 30,465 |
| Pierce | Washington | 359 | 1,138,508 | 14,826 |
| Bergen | New Jersey | 49 | 1,133,521 | 6,905 |
| Honolulu | Hawaii | 40 | 1,128,562 | 1,423 |
| San Juan Municipio | Puerto Rico | 4 | 1,077,982 | 1,811 |
| Fresno | California | 340 | 1,053,609 | 11,624 |
| San Francisco | California | 8 | 1,040,304 | 77 |
| Kern | California | 341 | 1,032,343 | 11,890 |
| Westchester | New York | 274 | 992,853 | 15,832 |
| Gwinnett | Georgia | 4 | 984,825 | 322 |
| El Paso | Texas | 39 | 956,978 | 6,717 |
| Erie | New York | 108 | 955,615 | 7,606 |
| Milwaukee | Wisconsin | 85 | 953,104 | 2,602 |
| Marion | Indiana | 56 | 949,929 | 5,652 |
| Snohomish | Washington | 170 | 947,238 | 8,193 |
| Duval | Florida | 93 | 938,751 | 3,651 |
| Davidson | Tennessee | 4 | 924,319 | 394 |
| Hidalgo | Texas | 31 | 921,483 | 5,096 |
| Essex | Massachusetts | 67 | 908,499 | 3,080 |
| Essex | New Jersey | 25 | 889,677 | 4,186 |
| Oklahoma | Oklahoma | 121 | 889,384 | 20,669 |
| Fort Bend | Texas | 289 | 886,088 | 8,810 |
| Ventura | California | 95 | 882,799 | 1,507 |
| Arapahoe | Colorado | 40 | 864,434 | 5,553 |
| DuPage | Illinois | 207 | 861,775 | 15,779 |
| Multnomah | Oregon | 57 | 854,646 | 4,422 |
| Hamilton | Ohio | 28 | 842,267 | 1,480 |
| Norfolk | Massachusetts | 57 | 842,114 | 2,645 |
| Hartford | Connecticut | 219 | 836,032 | 20,244 |
| Macomb | Michigan | 93 | 830,956 | 2,728 |
| Shelby | Tennessee | 8 | 822,834 | 604 |
| Denton | Texas | 98 | 811,262 | 10,762 |
| Jefferson | Alabama | 14 | 807,140 | 493 |
| Cobb | Georgia | 5 | 803,382 | 38 |
| San Mateo | California | 52 | 782,067 | 1,318 |
| Fairfield | Connecticut | 336 | 779,265 | 42,084 |
| Union | New Jersey | 7 | 778,855 | 855 |
| San Joaquin | California | 310 | 775,760 | 5,057 |
| Worcester | Massachusetts | 345 | 773,172 | 23,751 |
| Montgomery | Texas | 458 | 771,444 | 18,154 |
| Jefferson | Kentucky | 1 | 764,769 | 660 |
| El Paso | Colorado | 140 | 757,938 | 21,020 |
| DeKalb | Georgia | 1 | 743,000 | 8 |
| Brevard | Florida | 82 | 738,073 | 4,351 |
| Utah | Utah | 85 | 734,522 | 16,257 |
| Lee | Florida | 79 | 730,128 | 1,575 |
| New Haven | Connecticut | 212 | 723,250 | 17,543 |
| Ocean | New Jersey | 214 | 721,554 | 10,195 |
| Lake | Illinois | 540 | 719,035 | 33,311 |
| Monmouth | New Jersey | 285 | 715,264 | 9,403 |
| Adams | Colorado | 86 | 711,442 | 11,205 |
| Williamson | Texas | 52 | 703,146 | 2,502 |
| Burlington | New Jersey | 293 | 674,987 | 19,188 |
| Bristol | Massachusetts | 133 | 673,471 | 3,611 |
Page 1 of 33 Next →