Question 1

What state has the cleanest tap water?

Accepted Answer

Hawaii has the cleanest tap water in the US, ranking #1 with a grade of A and a score of 99.9 out of 100. The top 5 states for water quality are Hawaii, North Carolina, New Hampshire, Louisiana, Alaska.

Question 2

What state has the best water quality?

Accepted Answer

Hawaii has the best overall water quality based on population-weighted EPA data. Scores are calculated from city-level contaminant testing results, with higher scores indicating fewer contaminants above health guidelines.

Question 3

What city has the cleanest tap water?

Accepted Answer

Skagway, Alaska has the cleanest tap water of any city in our database, with a water quality score of 100 out of 100. The city serves 9,411 people.

Question 4

Which states have the worst water quality?

Accepted Answer

Oklahoma currently has the most room for improvement in water quality, ranking last with a score of 72.6. The bottom 5 states are Oklahoma, Pennsylvania, Nevada, Kansas, Missouri. These rankings reflect contaminant levels relative to EPA health guidelines, not necessarily safety violations.

Question 5

How is water quality measured and ranked?

Accepted Answer

Our rankings are based on EPA Safe Drinking Water Information System (SDWIS) data and utility Consumer Confidence Reports. Each city receives a score from 0 to 100 based on contaminant testing results compared to EPA health guidelines. State scores are population-weighted averages of city scores, and grades range from A (best) to F.

Question 6

Is US tap water safe to drink?

Accepted Answer

US tap water generally meets EPA legal limits (Maximum Contaminant Levels) and is considered safe to drink. However, health-based guidelines (MCLGs) are often stricter than legal limits. Many cities have contaminants above these health guidelines. Search your city to see detailed water quality data for your area.

Question 7

What contaminants are found in US tap water?

Accepted Answer

Common contaminants found in US tap water include disinfection byproducts (like trihalomethanes and haloacetic acids), PFAS (forever chemicals), lead from aging pipes, nitrate from agricultural runoff, and arsenic from natural deposits. The specific contaminants vary by location. Visit our contaminants page for detailed information.

Question 8

How does my state's water compare?

Accepted Answer

Use the rankings table above to find your state and see its grade, score, and ranking. You can also click on any state to see city-level data, or search for your specific city at the top of this site for detailed contaminant information and filter recommendations.

Rank	State	Grade	Score	Cities Tested	Population
1	Hawaii	A	99.9	30	10,393,426
2	North Carolina	A	99.7	260	32,288,327
3	New Hampshire	A	99.5	37	640,451
4	Louisiana	A	98.9	141	6,517,644
5	Alaska	A	97.7	13	420,015
6	South Dakota	A	96.5	38	480,246
7	New Mexico	A	95.9	69	5,465,379
8	Indiana	A	95.2	164	26,818,524
9	Oregon	A	90.5	110	7,978,872
10	Vermont	A	88.2	26	109,055
11	Tennessee	A	87.6	183	16,002,403
12	Massachusetts	A	87.3	166	7,307,382
13	Colorado	A	86.7	156	57,172,929
14	Rhode Island	A	85.8	18	892,579
15	Maine	A	85.6	39	493,369
16	Washington	A	85.6	262	37,460,278
17	Maryland	A	85.4	133	64,990,436
18	District of Columbia	A	85.0	1	665,214
19	Georgia	A	84.8	218	42,789,537
20	Mississippi	A	84.6	128	1,814,205
21	Wyoming	A	84.3	23	288,327
22	Alabama	A	84.1	186	6,756,463
23	North Dakota	A	84.0	29	531,888
24	Arkansas	A	83.7	142	7,982,065
25	California	A	83.7	765	236,998,735
26	South Carolina	A	83.4	137	17,248,317
27	Michigan	A	83.1	205	12,294,604
28	New York	A	83.1	357	89,997,343
29	Virginia	A	83.0	172	38,896,277
30	Montana	A	82.4	29	416,712
31	West Virginia	A	82.3	68	845,071
32	Iowa	A	81.7	128	8,318,498
33	Idaho	A	81.7	53	2,963,071
34	Delaware	A	81.3	29	5,648,314
35	Nebraska	A	81.3	45	1,140,191
36	Ohio	A	81.0	266	45,758,445
37	Florida	A	80.6	386	76,275,724
38	Kentucky	A	80.5	114	7,977,671
39	Connecticut	A	80.1	105	26,913,772
40	New Jersey	B	79.8	402	113,905,849
41	Minnesota	B	78.8	182	5,181,179
42	Texas	B	78.1	647	58,553,444
43	Wisconsin	B	77.7	173	4,653,277
44	Arizona	B	77.4	87	24,899,771
45	Utah	B	77.3	90	5,225,355
46	Illinois	B	76.8	315	22,194,246
47	Missouri	B	76.2	186	14,687,665
48	Kansas	B	76.1	125	10,788,981
49	Nevada	B	76.1	27	5,597,760
50	Pennsylvania	B	75.9	589	157,219,393
51	Oklahoma	B	72.6	154	10,205,847

Rank	City	State	Score	Population
1	Skagway	Alaska	100	9,411
2	Daphne	Alabama	100	52,098
3	Gordo	Alabama	100	3,630
4	Hodges	Alabama	100	2,400
5	Loxley	Alabama	100	10,104
6	Reform	Alabama	100	2,376
7	Silverhill	Alabama	100	1,572
8	Redfield	Arkansas	100	2,865
9	Peach Springs	Arizona	100	2,080
10	Sacaton	Arizona	100	25,398
11	Tuba City	Arizona	100	1,740
12	Upper Santan Village	Arizona	100	5,307
13	Whiteriver	Arizona	100	15,570
14	Allendale	California	100	1,313
15	Angwin	California	100	4,720
16	Antelope	California	100	277,124
17	Apple Valley	California	100	90,156
18	Arden-Arcade	California	100	212,940
19	Arvin	California	100	19,895
20	Atwater	California	100	31,129
21	Auburn Lake Trails	California	100	9,112
22	Avocado Heights	California	100	260,411
23	Bell	California	100	87,290
24	Bermuda Dunes	California	100	278,948
25	Biggs	California	100	1,805

Rank	City	State	Score	Population
1	Antelope	California	100	277,124
2	Arden-Arcade	California	100	212,940
3	Avocado Heights	California	100	260,411
4	Bermuda Dunes	California	100	278,948
5	Carmichael	California	100	385,467
6	Citrus Heights	California	100	308,799
7	Coachella	California	100	315,769
8	Coloma	California	100	139,799
9	Fairfield	California	100	137,375
10	Foothill Farms	California	100	242,087

Rank	City	State	Score	Population
1	Philadelphia	Pennsylvania	65	1,600,110
2	Stringtown	Oklahoma	65	645,105
3	Pink	Oklahoma	65	645,200
4	Phillips	Oklahoma	65	644,140
5	Oklahoma City	Oklahoma	65	719,824
6	Lehigh	Oklahoma	65	644,000
7	Konawa	Oklahoma	65	644,000
8	South Lake Tahoe	California	65	115,588
9	Meyers	California	65	109,414
10	Madison	Wisconsin	70	277,395

Rank	City	State	Score	Population
1	Sioux City	Iowa	60	85,797
2	Whitefish Bay	Wisconsin	65	49,870
3	Shorewood	Wisconsin	65	48,787
4	River Hills	Wisconsin	65	48,481
5	Glendale	Wisconsin	65	48,481
6	Fox Point	Wisconsin	65	42,406
7	Darlington	Wisconsin	65	2,235
8	Bristol	Wisconsin	65	598
9	Arcadia	Wisconsin	65	3,737
10	Philadelphia	Pennsylvania	65	1,600,110
11	Horsham	Pennsylvania	65	37,901
12	Stringtown	Oklahoma	65	645,105
13	Pink	Oklahoma	65	645,200
14	Phillips	Oklahoma	65	644,140
15	Oklahoma City	Oklahoma	65	719,824
16	Lehigh	Oklahoma	65	644,000
17	Konawa	Oklahoma	65	644,000
18	South Lake Tahoe	California	65	115,588
19	Meyers	California	65	109,414
20	Waukesha	Wisconsin	70	72,098
21	Watertown	Wisconsin	70	24,268
22	Verona	Wisconsin	70	10,619
23	Suamico	Wisconsin	70	4,459
24	Oconomowoc	Wisconsin	70	16,605
25	Monona	Wisconsin	70	7,801

State Water Quality Rankings 2026

Key Findings

What State Has the Cleanest Tap Water?

All States Ranked

Which Cities Have the Cleanest Tap Water in the US?

Water Quality Rankings for Major US Cities

Best Water Quality — Major Cities

Most Room for Improvement — Major Cities

States and Cities With the Worst Water Quality

Bottom 10 States

Bottom 25 Cities

Rankings Change. Stay Ahead.

Frequently Asked Questions About US Water Quality Rankings

What state has the cleanest tap water?

What state has the best water quality?

What city has the cleanest tap water?

Which states have the worst water quality?

How is water quality measured and ranked?

Is US tap water safe to drink?

What contaminants are found in US tap water?

How does my state's water compare?

Methodology

Data Sources

Scoring Criteria

Check Your City's Water Quality

Stay Informed About Your Water Quality