B65/100

Colorado Tap Water Quality Rankings 2026

181 cities · 6,977,932 people served

Top Contaminant Concerns

Copper (90th percentile)PFOSPFOA

All Cities in Colorado

#	City	Score	Population	Violations
1	Denver	B (77)	1,358,630	191
2	Aurora	C (43)	599,537	749
3	Colorado Springs	C (45)	561,279	527
4	Fort Collins	B (66)	303,994	293
5	Lakewood	A (90)	246,159	138
6	Thornton	A (89)	230,551	31
7	Westminster	A (92)	203,195	12
8	Arvada	A (90)	173,220	6
9	Boulder	B (78)	167,180	12
10	Greeley	A (85)	139,972	20
11	Pueblo	C (53)	125,375	120
12	Littleton	A (86)	121,247	82
13	Grand Junction	A (88)	118,536	17
14	Castle Rock	C (58)	112,478	75
15	Broomfield	A (83)	109,023	28
16	Longmont	B (72)	106,066	42
17	Centennial	B (66)	105,000	173
18	Parker	F (0)	104,145	474
19	Highlands Ranch	A (90)	103,444	4
20	Englewood	B (64)	99,754	111
21	Loveland	A (90)	95,471	7
22	Commerce City	A (100)	74,341	0
23	Brighton	C (45)	63,506	60
24	Golden	B (64)	52,208	66
25	Vail	B (75)	51,515	22
26	Montrose	A (89)	49,156	33
27	Northglenn	A (90)	48,927	7
28	Fort Carson	A (91)	48,000	6
29	Durango	C (49)	41,024	180
30	Erie	C (52)	40,061	38
31	Berthoud	C (50)	39,865	61
32	Canon City	C (56)	38,800	69
33	Wheat Ridge	A (82)	36,283	48
34	Clifton	B (76)	34,500	13
35	Aspen	F (17)	31,100	76
36	Monument	C (44)	31,008	270
37	Pueblo West	C (42)	30,000	39
38	Lafayette	F (10)	28,700	67
39	Steamboat Springs	D (32)	28,380	205
40	Breckenridge	D (20)	28,315	61
41	Firestone	A (86)	27,798	11
42	Fountain	D (25)	26,430	186
43	Windsor	A (87)	26,164	24
44	Johnstown	F (0)	24,725	93
45	Louisville	C (51)	20,975	41
46	Estes Park	C (43)	20,452	177
47	Evans	A (86)	20,394	16
48	Niwot	D (24)	20,280	69
49	Fort Morgan	B (63)	20,116	47
50	Greenwood Village	A (89)	18,931	30
51	Falcon	D (23)	18,882	645
52	Superior	D (25)	17,900	52
53	Frederick	A (84)	17,173	13
54	Usaf Academy	B (60)	16,876	25
55	Wellington	C (54)	16,175	70
56	Lucerne	A (96)	15,890	1
57	Evergreen	B (77)	15,750	12
58	Dolores	A (81)	15,423	25
59	Gypsum	C (45)	15,272	48
60	Black Hawk	F (1)	15,167	96
61	Sterling	F (0)	15,100	74
62	Fort Lupton	C (40)	13,359	119
63	Castle Pines	D (29)	12,800	71
64	Peyton	C (47)	12,760	53
65	Alamosa	F (3)	12,724	253
66	Glenwood Springs	C (40)	12,368	150
67	Winter Park	D (27)	12,035	243
68	Severance	A (87)	11,733	10
69	Federal Heights	A (96)	11,678	1
70	Trinidad	F (0)	11,400	124
71	Pagosa Springs	F (0)	11,069	130
72	Silverthorne	D (38)	11,064	143
73	Idaho Springs	F (0)	10,432	39
74	Keystone	D (32)	9,900	65
75	Morrison	F (5)	9,887	92
76	Redvale	F (0)	9,700	152
77	Gunnison	B (75)	9,610	10
78	Rifle	D (20)	9,489	65
79	Milliken	F (0)	9,200	116
80	Craig	C (57)	8,930	40
81	Dillon	A (87)	8,818	21
82	Cortez	F (13)	8,770	76
83	Delta	A (89)	8,700	4
84	Woodland	C (52)	8,500	41
85	La Junta	D (36)	8,320	37
86	Telluride	F (0)	7,900	85
87	Eagle	C (58)	7,511	31
88	Florence	F (8)	7,500	81
89	Lamar	B (62)	7,500	35
90	Leadville	F (0)	7,500	416
91	Eaton	A (81)	7,328	12
92	Basalt	A (92)	6,945	13
93	Manitou Springs	D (39)	6,938	42
94	Dacono	A (84)	6,900	5
95	Lochbuie	C (49)	6,830	39
96	Carbondale	D (39)	6,700	30
97	Limon	B (72)	6,369	25
98	Snowmass Village	B (76)	6,353	16
99	New Castle	C (42)	6,184	105
100	Copper Mountain	A (83)	5,785	2
101	Salida	C (56)	5,666	44
102	Buena Vista	F (13)	5,476	163
103	Fraser	A (85)	5,400	16
104	Georgetown	C (52)	5,315	37
105	Edgewater	A (93)	5,300	4
106	Cedaredge	D (29)	5,200	100
107	Hillrose	B (73)	5,122	8
108	Keenesburg	D (25)	4,650	52
109	Monte Vista	A (80)	4,600	4
110	Elizabeth	D (22)	4,523	63
111	Frisco	F (0)	4,495	256
112	Rocky Ford	F (12)	4,443	80
113	Crested Butte	D (34)	4,440	89
114	Bennett	C (59)	4,400	18
115	Glendale	A (99)	4,400	1
116	Granby	A (84)	4,325	10
117	Ault	A (90)	4,220	7
118	Administrative Contact	F (0)	4,100	113
119	Yuma	F (0)	4,049	172
120	La Porte	B (67)	4,000	18
121	Bayfield	A (82)	3,999	17
122	Hayden	C (55)	3,915	18
123	Larkspur	C (47)	3,890	50
124	Central City	A (80)	3,750	16
125	Burlington	F (0)	3,720	316
126	Silt	F (1)	3,536	68
127	Watkins	C (57)	3,527	80
128	Hudson	F (0)	3,350	58
129	Mount Crested Butte	A (94)	3,296	6
130	Walsenburg	F (0)	3,230	86
131	Penrose	C (54)	3,149	23
132	Austin	B (75)	3,100	22
133	Palisade	F (0)	3,060	131
134	Olathe	A (93)	3,015	4
135	Lyons	F (0)	2,990	35
136	Platteville	B (76)	2,900	13
137	Cripple Creek	B (76)	2,817	17
138	Colorado City	F (0)	2,755	129
139	Mancos	C (41)	2,690	102
140	Palmer Lake	C (57)	2,686	40
141	Center	B (64)	2,575	36
142	Holyoke	B (79)	2,540	9
143	Paonia	F (0)	2,499	154
144	Rangely	C (52)	2,495	33
145	Meeker	A (92)	2,473	5
146	Nederland	C (52)	2,406	25
147	Silverton	A (84)	2,387	9
148	Akron	F (0)	2,379	76
149	Wray	B (67)	2,342	33
150	Flagler	F (5)	2,160	87
151	Las Animas	B (77)	2,139	7
152	Kersey	A (80)	2,101	16
153	Hotchkiss	F (0)	2,050	184
154	Strasburg	B (63)	2,050	22
155	Grand Lake	A (88)	2,035	1
156	Towoac	F (3)	2,020	82
157	Lasalle	B (70)	2,010	26
158	Crestone	D (34)	2,006	55
159	Creede	B (73)	1,965	27
160	El Jebel	C (52)	1,962	33
161	Westcliffe	A (85)	1,950	15
162	Conifer	F (0)	1,941	65
163	Wiggins	D (30)	1,909	27
164	Kremmling	B (64)	1,859	24
165	Norwood	F (0)	1,700	94
166	Deer Trail	F (0)	1,648	145
167	Ignacio	A (83)	1,527	14
168	Wiley	F (0)	1,500	599
169	Poncha Springs	B (78)	1,467	10
170	Ouray	F (0)	1,460	113
171	Del Norte	F (0)	1,429	95
172	Springfield	B (71)	1,378	10
173	Parachute	C (58)	1,320	35
174	Indian Hills	D (30)	1,300	27
175	Ordway	D (25)	1,300	75
176	Julesburg	B (62)	1,225	19
177	Minturn	B (66)	1,200	15
178	Fowler	F (0)	1,169	45
179	Gilcrest	A (82)	1,150	7
180	Pierce	D (29)	1,094	64
181	Log Lane Village	B (71)	1,006	21