What to know
Biennially, CDC summarizes WFRS data into National Water Fluoridation Statistics. The 2020 statistics include the estimated proportion of the U.S. population receiving fluoridated water, and the estimated proportion of people on community water systems that receive fluoridated water, both nationally and in each state. These data were updated in July 2023.
2020 national water fluoridation statistics
| Total U.S. population, personsa | 331,501,080 |
|---|---|
| U.S. population on community water systems (CWS), personsb,c | 287,798,584 |
| Total U.S. population on fluoridated drinking water systems, personsb,c | 209,145,650 |
| Percentage of U.S. population receiving fluoridated waterc,d | 62.9% |
| Percentage of U.S. population on CWS receiving fluoridated waterc,e | 72.7% |
| Total number of CWS in United Statesb | 51,373 |
| Number of CWS providing fluoridated waterb | 17,558 |
| Number of CWS adjusting fluorideb | 5,728 |
| Number of CWS consecutive to systems with optimal fluoride levelsb | 5,696 |
| Number of CWS with naturally occurring fluoride at or above optimal levelsb | 5,636 |
| Population served by CWS with naturally occurring fluoride at or above optimal levelsb,c | 11,578,079 |
2020 state fluoridation percentage calculations and ranking
| State | Persons Receiving Fluoridated Waterc | Persons Served by CWSc | % Population Served by CWS Receiving Fluoridated Water | Rankf |
|---|---|---|---|---|
| U.S. | 209,145,650 | 287,798,584 | 72.7 | |
| Alabama | 3,469,133 | 4,467,001 | 77.7 | 24 |
| Alaska | 229,789 | 545,179 | 42.1 | 45 |
| Arizona | 4,011,354 | 6,948,635 | 57.7 | 39 |
| Arkansas | 2,458,935 | 2,866,138 | 85.8 | 20 |
| California | 21,879,582 | 38,051,212 | 57.5 | 40 |
| Colorado | 4,123,671 | 5,480,628 | 75.2 | 28 |
| Connecticut | 2,473,983 | 2,736,539 | 90.4 | 14 |
| Delaware | 609,473 | 801,422 | 76 | 27 |
| District of Columbia | 690,093 | 690,093 | 100 | 1 |
| Florida | 14,886,493 | 18,952,021 | 78.5 | 23 |
| Georgia | 8,671,136 | 9,135,654 | 94.9 | 7 |
| Hawaii | 119,044 | 1,394,816 | 8.5 | 51 |
| Idaho | 441,664 | 1,405,388 | 31.4 | 47 |
| Illinois | 11,457,094 | 11,640,823 | 98.4 | 4 |
| Indiana | 4,683,083 | 5,066,252 | 92.4 | 11 |
| Iowa | 2,409,673 | 2,684,404 | 89.8 | 15 |
| Kansas | 1,820,664 | 2,785,355 | 65.4 | 34 |
| Kentucky | 4,050,483 | 4,055,441 | 99.9 | 2 |
| Louisiana | 1,582,811 | 4,161,676 | 38 | 46 |
| Maine | 544,916 | 685,410 | 79.5 | 22 |
| Maryland | 4,410,410 | 4,709,311 | 93.7 | 9 |
| Massachusetts | 3,691,328 | 6,385,621 | 57.8 | 38 |
| Michigan | 6,638,231 | 7,432,372 | 89.3 | 16 |
| Minnesota | 4,432,008 | 4,483,603 | 98.8 | 3 |
| Mississippi | 1,542,928 | 2,527,257 | 61.1 | 36 |
| Missouri | 3,843,523 | 5,323,578 | 72.2 | 30 |
| Montana | 240,294 | 765,861 | 31.4 | 48 |
| Nebraska | 1,317,170 | 1,784,114 | 73.8 | 29 |
| Nevada | 2,220,915 | 2,906,645 | 76.4 | 26 |
| New Hampshire | 398,698 | 863,017 | 46.2 | 44 |
| New Jersey | 1,333,544 | 8,279,024 | 16.1 | 50 |
| New Mexico | 1,398,194 | 1,820,853 | 76.8 | 25 |
| New York | 12,596,165 | 17,610,152 | 71.5 | 31 |
| North Carolina | 6,985,222 | 7,950,174 | 87.9 | 18 |
| North Dakota | 705,703 | 731,260 | 96.5 | 5 |
| Ohio | 9,177,890 | 9,901,174 | 92.7 | 10 |
| Oklahoma | 2,447,980 | 3,600,546 | 68 | 33 |
| Oregon | 944,045 | 3,576,686 | 26.4 | 49 |
| Pennsylvaniag | 5,680,881 | 9,468,135 | 60 | 37 |
| Rhode Island | 809,308 | 979,110 | 82.7 | 21 |
| South Carolina | 3,567,836 | 3,891,342 | 91.7 | 12 |
| South Dakota | 710,136 | 757,461 | 93.8 | 8 |
| Tennessee | 5,592,155 | 6,296,831 | 88.8 | 17 |
| Texas | 19,743,163 | 27,818,869 | 71 | 32 |
| Utah | 1,637,472 | 3,214,451 | 50.9 | 43 |
| Vermont | 221,018 | 392,292 | 56.3 | 41 |
| Virginia | 6,713,205 | 7,027,639 | 95.5 | 6 |
| Washington | 4,304,476 | 6,616,621 | 65.1 | 35 |
| West Virginia | 1,277,174 | 1,409,744 | 90.9 | 13 |
| Wisconsin | 3,695,850 | 4,260,757 | 86.7 | 19 |
| Wyoming | 255,654 | 459,997 | 55.6 | 42 |
Footnotes
a Census Population Count 2020. Annual Estimates of the Resident Population for the United States, Regions, States, District of Columbia, and Puerto Rico: April 1, 2020, to July 1, 2021 (NST-EST2021-POP); 2021. Source: U.S. Census Bureau, Population Division. Accessed April 9, 2024. https://www2.census.gov/programs-surveys/popest/tables/2020-2021/state/totals/
b Reported in CDC Water Fluoridation Reporting System (WFRS). For this report, a water system is considered a community water system (CWS) if so, designated by the state drinking water administrator, in accordance with the regulatory requirements of the U.S. Environmental Protection Agency. A CWS supplies water to the same population year-round and serves at least 25 people at their primary residences or at least 15 residences that are primary residences (for example, municipalities, mobile home park, sub-divisions). https://www.epa.gov/dwreginfo/information-about-public-water-systems
c Estimates of state populations served by CWSs and reported in WFRS are controlled by using a product of the U.S. Census state population estimate and the U.S. Geological Survey's estimate of the percentages of state populations that are on public water systems. Estimates for populations served by each CWS are controlled proportionately within each state. For details on the population-controlling method used, see Calculating Fluoridation Statistics. U.S. Geological Survey: Dieter CA, Maupin MA, Caldwell RR, et al. Estimated use of water in the United States in 2015: U.S. Geological Survey Circular 1441; 2018. https://doi.org/10.3133/cir1441 [Supersedes USGS Open-File Report 2017–1131.]
d Fluoridated population divided by total population.
e Fluoridated population divided by population served by CWSs.
f Based on highest to lowest percentage of population served by CWS receiving fluoridated water. Includes all states and Washington, DC (51 total rankings).
g Complete data were not available from WFRS. State provided additional information.