Multiple Sources · 38 states
States With Best Water Quality
Access to clean, safe drinking water is fundamental to public health, yet water quality varies significantly. Water quality is regulated under the Safe Drinking Water Act, which sets maximum contaminant levels for over 90 pollutants. Common issues include lead from aging pipes, PFAS chemicals, agricultural runoff, and disinfection byproducts. The Flint crisis brought national attention to the millions of Americans receiving substandard water. States investing in infrastructure modernization and source water protection are seeing measurable improvements.
Key Findings
- 1California leads with a water safety score of 99, followed by Washington (98) and Virginia (97).
- 2New Jersey ranks last at 61, while California leads at 99.
- 3The national median across all states is 82 (North Carolina at the midpoint).
- 4The top 10 states are: California, Washington, Virginia, Arkansas, Tennessee, Nevada, Texas, Wisconsin, Kentucky, Minnesota.
Full Ranking: States With Best Water Quality
Source: Census ACS 2023 5-Year Estimates
| # | State | Safety Score | Systems w/ Violations |
|---|---|---|---|
| 1 | Wisconsin | 92 | 1 |
| 2 | West Virginia | 85 | 2 |
| 3 | Washington | 98 | 0 |
| 4 | Virginia | 97 | 0 |
| 5 | Utah | 75 | 2 |
| 6 | Texas | 92 | 0 |
| 7 | Tennessee | 94 | 0 |
| 8 | South Carolina | 71 | 2 |
| 9 | Pennsylvania | 86 | 2 |
| 10 | Oregon | 85 | 2 |
| 11 | Oklahoma | 82 | 1 |
| 12 | Ohio | 71 | 3 |
| 13 | North Carolina | 82 | 3 |
| 14 | New York | 74 | 3 |
| 15 | New Mexico | 68 | 3 |
| 16 | New Jersey | 61 | 5 |
| 17 | Nevada | 92 | 0 |
| 18 | Nebraska | 70 | 3 |
| 19 | Missouri | 86 | 2 |
| 20 | Mississippi | 70 | 1 |
| 21 | Minnesota | 87 | 1 |
| 22 | Michigan | 80 | 2 |
| 23 | Massachusetts | 74 | 3 |
| 24 | Maryland | 74 | 2 |
| 25 | Louisiana | 73 | 2 |
| 26 | Kentucky | 89 | 2 |
| 27 | Kansas | 84 | 2 |
| 28 | Iowa | 76 | 2 |
| 29 | Indiana | 86 | 2 |
| 30 | Illinois | 85 | 2 |
| 31 | Georgia | 77 | 2 |
| 32 | Florida | 82 | 3 |
| 33 | Connecticut | 82 | 3 |
| 34 | Colorado | 79 | 2 |
| 35 | California | 99 | 0 |
| 36 | Arkansas | 96 | 1 |
| 37 | Arizona | 62 | 4 |
| 38 | Alabama | 62 | 2 |
Methodology
Rankings are based on American Community Survey (ACS) 2023 5-Year estimates from the US Census Bureau. All 50 states and the District of Columbia are included. The ACS surveys approximately 3.5 million households annually and provides detailed demographic, social, economic, and housing data. 5-Year estimates offer the most reliable data for state-level comparisons by averaging responses over a 60-month period. Percentages may not sum to 100% due to rounding.
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Frequently Asked Questions
California has the highest water safety score at 99, according to Census ACS 2023 data. Washington and Virginia round out the top three.
New Jersey has the lowest water safety score at 61. Arizona is second-lowest at 62.
The median across all 38 states is 82. Note that the national median and the state-level median are calculated differently — the state median represents the midpoint when all states are ranked.
This data comes from the American Community Survey (ACS) 2023 5-Year estimates published by the US Census Bureau. The ACS surveys approximately 3.5 million households annually and provides the most comprehensive demographic data available between decennial censuses.
Rankings are based on the latest available Census ACS data (currently 2023 5-Year estimates). The Census Bureau releases new ACS data annually, typically in September. Our data was last updated on April 12, 2026.
Rankings are based on American Community Survey (ACS) 2023 5-Year estimates from the US Census Bureau. All 50 states and the District of Columbia are included. The ACS surveys approximately 3.5 million households annually and provides detailed demographic, social, economic, and housing data. 5-Year estimates offer the most reliable data for state-level comparisons by averaging responses over a 60-month period. Percentages may not sum to 100% due to rounding.