State Drinking Water Report Cards

Every state graded A through F on drinking water safety, based on EPA violation data. Grades are calculated from two factors: health-based violations per 100,000 people served (60% weight) and percentage of systems with active health violations (40% weight).

States are sorted worst-first. A high grade doesn't mean perfect water — it means fewer violations relative to the population served. Click any state to see county-level detail.

0Grade A

1Grade B

1Grade C

0Grade D

54Grade F

Grade	State	Systems	Population	Health Violations	Per 100K	Active Health
F	Oklahoma	1,280	3,723,482	29,030	779.6	219
F	Alaska	1,290	855,068	5,896	689.5	93
F	American Samoa	91	50,626	281	555.1	2
F	New Mexico	1,119	2,128,367	9,335	438.6	238
F	Vermont	1,263	634,882	2,222	350.0	37
F	Northern Mariana Islands	60	70,193	194	276.4	0
F	Louisiana	1,141	5,250,528	14,234	271.1	273
F	Maine	1,749	922,370	2,096	227.2	76
F	Montana	2,220	1,144,916	2,575	224.9	72
F	Wyoming	737	638,388	1,416	221.8	43
F	New Hampshire	2,266	1,169,538	2,454	209.8	18
F	Idaho	1,957	1,752,980	3,535	201.7	62
F	Arkansas	875	3,048,056	6,108	200.4	14
F	West Virginia	777	1,595,310	3,015	189.0	182
F	Nebraska	1,245	1,802,604	2,728	151.3	1
F	South Dakota	715	967,590	1,324	136.8	17
F	Kansas	1,049	2,901,247	3,883	133.8	20
F	Pennsylvania	7,393	12,631,018	15,600	123.5	432
F	Texas	7,131	33,114,811	38,542	116.4	559
F	Missouri	2,998	6,021,914	6,995	116.2	48
F	Colorado	2,267	7,500,550	7,439	99.2	91
F	Oregon	2,517	4,021,013	3,784	94.1	67
F	Connecticut	2,366	2,987,148	2,689	90.0	361
F	Puerto Rico	458	3,328,141	2,877	86.4	245
F	Arizona	1,729	7,736,675	6,330	81.8	146
F	Indiana	3,801	5,738,395	4,594	80.1	112
F	Wisconsin	10,630	5,120,293	3,713	72.5	83
F	Utah	1,202	3,895,151	2,494	64.0	44
F	California	8,328	42,711,809	26,750	62.6	863
F	Mississippi	1,166	3,282,490	1,951	59.4	30
F	US Virgin Islands	51	75,284	41	54.5	21
F	Washington	4,736	9,859,803	4,732	48.0	49
F	Nevada	669	3,536,677	1,694	47.9	52
F	New York	7,834	19,232,945	8,698	45.2	174
F	Iowa	1,817	3,121,827	1,337	42.8	16
F	New Jersey	3,526	9,548,382	4,007	42.0	187
F	Kentucky	445	4,621,584	1,822	39.4	8
F	North Carolina	5,140	9,894,936	3,572	36.1	71
F	Minnesota	6,691	5,299,221	1,911	36.1	22
F	Illinois	4,747	12,593,615	4,530	36.0	241
F	Rhode Island	450	1,145,569	381	33.3	5
F	Virginia	2,794	7,868,815	2,391	30.4	20
F	Delaware	470	1,096,992	319	29.1	4
F	North Dakota	406	751,175	211	28.1	4
F	Georgia	2,382	10,689,689	2,786	26.1	13
F	Maryland	3,123	5,931,883	1,426	24.0	40
F	Michigan	10,776	9,137,852	2,186	23.9	68
F	Ohio	4,157	11,088,144	2,467	22.2	80
F	Tennessee	1,904	8,069,718	1,535	19.0	18
F	Florida	4,836	22,346,930	3,905	17.5	296
F	South Carolina	1,174	4,698,518	800	17.0	15
F	Massachusetts	1,840	10,380,510	1,679	16.2	53
F	District of Columbia	26	700,503	59	8.4	3
F	Alabama	630	6,155,101	498	8.1	13
C	Hawaii	136	1,519,931	39	2.6	1
B	Guam	9	314,651	6	1.9	0

Methodology

Grades are calculated using two metrics from EPA SDWIS data:

Health violations per 100,000 people — total health-based violations divided by population served, normalized per 100K. Weight: 60%.
Active health violation rate — percentage of active water systems with at least one unresolved health-based violation. Weight: 40%.

The combined score maps to letter grades: A (<0.5), B (0.5-1.5), C (1.5-3.0), D (3.0-5.0), F (>5.0).