B64/100

Wyoming Tap Water Quality Rankings 2026

54 cities · 481,630 people served

Top Contaminant Concerns

Copper (90th percentile)PFHxSPFOS

#	City	Score	Population	Violations
1	Cheyenne	B (72)	75,243	47
2	Casper	A (83)	64,828	29
3	Gillette	B (79)	35,902	31
4	Laramie	B (78)	32,395	15
5	Rock Springs	A (94)	27,000	5
6	Jackson	F (0)	24,760	191
7	Sheridan	B (63)	22,700	14
8	Cody	A (93)	17,554	9
9	Yellowstone	C (41)	13,600	59
10	Evanston	A (82)	12,000	3
11	Green River	A (88)	10,500	5
12	Riverton	B (67)	10,330	6
13	Rawlins	F (11)	9,006	58
14	Lander	D (31)	7,615	61
15	Torrington	F (0)	6,847	28
16	Douglas	B (79)	6,400	10
17	Moose	A (96)	6,344	3
18	Powell	A (95)	6,310	2
19	F.E. Warren Afb	B (74)	5,500	14
20	Worland	B (77)	5,487	16
21	Fort Washakie	F (0)	5,470	367
22	Buffalo	F (3)	4,419	30
23	Mills	A (80)	4,050	8
24	Bar Nunn	A (80)	4,000	13
25	Wheatland	F (0)	3,659	127
26	Newcastle	F (0)	3,595	184
27	Kemmerer	F (0)	3,348	28
28	Greybull	F (5)	3,260	84
29	Ethete	F (0)	3,100	357
30	Mountain View	B (60)	2,978	46
31	Wilson	D (38)	2,900	133
32	Thermopolis	B (68)	2,775	25
33	Yellowstone National Park	A (84)	2,600	9
34	Wright	A (90)	2,500	7
35	Glenrock	B (77)	2,466	8
36	Lovell	B (76)	2,360	24
37	Lyman	B (73)	2,203	20
38	Star Valley Ranch	F (18)	2,030	51
39	Little America	F (0)	2,004	66
40	Afton	D (30)	2,000	43
41	Grover	F (0)	1,910	374
42	Pinedale	F (0)	1,900	58
43	Dubois	F (0)	1,870	133
44	Saratoga	D (37)	1,720	39
45	Lusk	F (0)	1,576	118
46	Alpine	D (20)	1,300	45
47	Ranchester	A (88)	1,297	8
48	Sundance	B (73)	1,279	8
49	Basin	B (77)	1,250	12
50	Bear River	C (44)	1,200	24
51	Guernsey	F (0)	1,157	79
52	Upton	A (83)	1,100	6
53	Burns	F (0)	1,024	130
54	Moorcroft	B (67)	1,009	21