Arsenic Contamination

Arsenic in Arizona Drinking Water

Ranked by arsenic violation count · Data from EPA SDWIS & UCMR

201

Cities Tested

201

Has Violations

100%

% Has Violations

19.7 violations

State Avg

▼ 0% vs national

vs National

221

Health Violations

Analysis

Arsenic in Arizona: what the data shows

Arizona has 201 cities with arsenic-related violations on record. Arsenic contamination is a federal MCL violation at levels above 10 µg/L (10 ppb). The state has 201 cities with at least one arsenic violation. Arsenic enters drinking water primarily through erosion of natural deposits, particularly in western states with arsenite-bearing geology. Industrial sources include mining runoff, glass manufacturing, and semiconductor production. Groundwater systems are significantly more likely to have arsenic issues than surface water systems. Long-term arsenic exposure above the MCL increases the risk of bladder, lung, and skin cancer, as well as cardiovascular disease and diabetes. Reverse osmosis and specialized arsenic-removal media are the most effective point-of-use treatment options.

Comparison

Cities exceeding 10 µg/L EPA MCL

Arizona

100%

201 of 201 cities

← = Exactly at national rate

National avg

100%

5270 of 5270 cities

City Map

Arsenic data across Arizona

Each dot is a city with arsenic violation data. Cities with at least one arsenic-related violation are highlighted. Size reflects population served.

Worst Offenders

Top 10 cities by arsenic level in Arizona

Highest Arsenic levels (violations)

All Cities

All Arizona cities ranked by arsenic level

#	City	Level	Violations?	Violations	Grade
1	Cottonwood	279 violations	Yes	184	D
2	Yuma	253 violations	Yes	318	F
3	Camp Verde	242 violations	Yes	149	D
4	Sedona	221 violations	Yes	174	F
5	Tucson	123 violations	Yes	150	F
6	Kingman	110 violations	Yes	110	D
7	Maricopa	107 violations	Yes	228	D
8	First Mesa Consolidated Villages	92 violations	Yes	74	D
9	Flagstaff	84 violations	Yes	74	D
10	Chino Valley	81 violations	Yes	48	D+
11	Shungopavi	71 violations	Yes	58	D+
12	Douglas	70 violations	Yes	55	D
13	Nogales	69 violations	Yes	39	F
14	Clifton	68 violations	Yes	37	D+
15	Pomerene	68 violations	Yes	19	D+
16	Buckeye	67 violations	Yes	103	F
17	San Carlos	66 violations	Yes	140	D
18	Phoenix	63 violations	Yes	59	F
19	Surprise	60 violations	Yes	18	F
20	Black Canyon City	60 violations	Yes	16	F
21	Aneth	57 violations	Yes	49	D+
22	Aneth	57 violations	Yes	52	D
23	Toadlena, Two Grey Hills	56 violations	Yes	51	D
24	Toadlena, Two Grey Hills	56 violations	Yes	51	D
25	Cornville	54 violations	Yes	21	F
26	Avra Valley	52 violations	Yes	32	B-
27	Show Low	48 violations	Yes	60	D
28	Tacna	48 violations	Yes	63	D
29	Green Valley	47 violations	Yes	9	D
30	Florence	46 violations	Yes	60	F
31	Tombstone	45 violations	Yes	26	D
32	Hopi High School	38 violations	Yes	46	D+
33	Red Mesa	37 violations	Yes	33	D
34	Cave Creek	34 violations	Yes	25	C-
35	Litchfield Park	33 violations	Yes	21	F
36	Bullhead City	33 violations	Yes	57	F
37	Globe	32 violations	Yes	46	F
38	Keams Canyon	32 violations	Yes	27	B
39	Chandler	29 violations	Yes	32	F
40	Middle Verde	29 violations	Yes	22	B-
41	Prescott	28 violations	Yes	33	F
42	Sierra Vista	28 violations	Yes	44	D
43	Parker	28 violations	Yes	148	F
44	Supai	23 violations	Yes	11	D+
45	Payson	22 violations	Yes	60	F
46	Paulden	22 violations	Yes	3	B
47	Gilbert	21 violations	Yes	11	F
48	Glendale	21 violations	Yes	5	F
49	Pioneer	21 violations	Yes	16	B
50	Peoria	20 violations	Yes	13	F
51	El Mirage	20 violations	Yes	3	D
52	Fountain Hills	20 violations	Yes	21	F
53	Sweetwater, Red Mesa	19 violations	Yes	18	C+
54	Wellton	16 violations	Yes	72	D
55	Eloy	15 violations	Yes	64	D
56	Red Mesa	15 violations	Yes	13	B-
57	White River	15 violations	Yes	20	B-
58	Sun City West	13 violations	Yes	3	B+
59	Paradise Valley	13 violations	Yes	3	C
60	Scottsdale	12 violations	Yes	22	F
61	Whiteriver	12 violations	Yes	7	D
62	Salt River Indian Community	11 violations	Yes	22	B
63	Lakeside	11 violations	Yes	15	D+
64	Humboldt	11 violations	Yes	10	A-
65	Tempe	10 violations	Yes	3	D+
66	Pine	10 violations	Yes	10	F
67	Fredonia	10 violations	Yes	1	C-
68	Sun City	9 violations	Yes	1	B
69	Apache Junction	9 violations	Yes	18	F
70	Bonita	9 violations	Yes	4	D
71	Lake Havasu City	8 violations	Yes	5	D
72	Stotonic, Goodyear, Gila Butte, Sweetwat	8 violations	Yes	11	B+
73	Huachuca City	8 violations	Yes	12	D
74	Mesa	7 violations	Yes	3	F
75	Safford	7 violations	Yes	9	D
76	Sahuarita	7 violations	Yes	19	F
77	Buckeye-Sono	7 violations	Yes	2	B-
78	Kearny	7 violations	Yes	14	D
79	Heber	7 violations	Yes	11	F
80	Adaman	7 violations	Yes	9	C-
81	Grand Canyon	6 violations	Yes	11	D
82	Pinetop	6 violations	Yes	12	D
83	Clarkdale	6 violations	Yes	0	B+
84	Tusayan	6 violations	Yes	18	D+
85	Cameron	6 violations	Yes	38	D
86	San Luis	5 violations	Yes	8	D
87	Fort Huachuca	5 violations	Yes	9	F
88	Page	5 violations	Yes	8	F
89	Snowflake	5 violations	Yes	1	C+
90	Topock	5 violations	Yes	13	C
91	Bagdad	5 violations	Yes	6	A-
92	Springerville	5 violations	Yes	16	F
93	Lukachukai	5 violations	Yes	4	A-
94	Oro Valley	4 violations	Yes	11	D
95	Marana	4 violations	Yes	13	F
96	Catalina	4 violations	Yes	2	D
97	Wickenburg	4 violations	Yes	21	F
98	Winslow	4 violations	Yes	9	D
99	Bisbee	4 violations	Yes	15	F
100	Benson	4 violations	Yes	29	D
101	Williams	4 violations	Yes	14	D+
102	Morenci	4 violations	Yes	15	C-
103	Quartzsite	4 violations	Yes	7	D+
104	Bylas	4 violations	Yes	65	D
105	Ajo	4 violations	Yes	0	B-
106	Ash Fork	4 violations	Yes	3	B
107	San Xavier West	4 violations	Yes	3	A-
108	Ganado	4 violations	Yes	3	D
109	Round Rock	4 violations	Yes	12	D+
110	Queen Creek	3 violations	Yes	14	D
111	Avondale	3 violations	Yes	13	C+
112	Rio Rico	3 violations	Yes	4	C
113	Somerton	3 violations	Yes	17	D
114	Holbrook	3 violations	Yes	6	F
115	Superior	3 violations	Yes	0	C-
116	Willcox	3 violations	Yes	7	D
117	Sr Boarding School, Sr Subdivision, Palo	3 violations	Yes	2	A
118	Tsaile, Dine College	3 violations	Yes	1	A
119	Spring Valley	3 violations	Yes	3	A-
120	Ehrenberg	3 violations	Yes	5	B
121	Linden	3 violations	Yes	3	C-
122	Wilhoit	3 violations	Yes	1	A-
123	Seligman	3 violations	Yes	0	A-
124	Hayden	3 violations	Yes	2	D
125	Wildhorse Pass Casino, St. Johns Komatke	2 violations	Yes	12	B+
126	White Tanks	2 violations	Yes	1	B+
127	Chinle, Many Farms, Del Muerto	2 violations	Yes	10	B+
128	Sacaton, Sacaton Flats,Upper San Tan, Bl	2 violations	Yes	11	B
129	Peach Springs	2 violations	Yes	30	C+
130	Taylor	2 violations	Yes	1	D
131	Mohave Valley	2 violations	Yes	14	F
132	Casa Blanca,Bapchule,Wet Camp,Sacate,Wes	2 violations	Yes	10	A-
133	Clints Well	2 violations	Yes	1	A-
134	New Lands (Sanders)	2 violations	Yes	2	A
135	Upper Moenkopi	2 violations	Yes	8	B-
136	Cottonwood, Tselani	2 violations	Yes	4	A
137	Organ Pipe Nm	2 violations	Yes	1	B
138	Goodyear	1 violations	Yes	3	F
139	Anthem	1 violations	Yes	1	B
140	Fort Defiance, Window Rock, St. Michaels	1 violations	Yes	22	B-
141	Tolleson	1 violations	Yes	1	B+
142	Munds Park	1 violations	Yes	1	A
143	Pinon, South Pinon, Burnt Corn, Blue Gap	1 violations	Yes	0	A
144	Eagar	1 violations	Yes	9	C
145	Pima	1 violations	Yes	11	F
146	Crownpoint, Littlewater, Three Mile Poin	1 violations	Yes	4	A
147	Crownpoint, Littlewater, Three Mile Poin	1 violations	Yes	4	A
148	Carefree	1 violations	Yes	0	A-
149	Big River	1 violations	Yes	7	D
150	Big River	1 violations	Yes	7	D
151	Saint Johns	1 violations	Yes	7	C+
152	Silverbell	1 violations	Yes	0	A
153	Dolan Springs	1 violations	Yes	12	C+
154	Bread Springs, Chichiltah	1 violations	Yes	3	A
155	Bread Springs, Chichiltah	1 violations	Yes	3	A
156	Sanostee, Tocito, Littlewater, Mittenroc	1 violations	Yes	0	A
157	Sanostee, Tocito, Littlewater, Mittenroc	1 violations	Yes	0	A
158	Joseph City	1 violations	Yes	0	C+
159	Hotevilla, Hotevilla/Bacavi Community Sc	1 violations	Yes	1	D+
160	Rock Springs	1 violations	Yes	0	A
161	Rock Springs	1 violations	Yes	0	A
162	Many Farms	1 violations	Yes	1	B-
163	Sunsites	1 violations	Yes	2	B+
164	South Komelic, Choulic, Cold Fields, Top	1 violations	Yes	1	A
165	Kykotsmovi	1 violations	Yes	1	A-
166	Centennial Park	1 violations	Yes	21	B-
167	St David	1 violations	Yes	22	D+
168	Mammoth	1 violations	Yes	2	C-
169	Naschitti, Bisola	1 violations	Yes	0	A
170	Naschitti, Bisola	1 violations	Yes	0	A
171	Bacavi	1 violations	Yes	0	B+
172	Huerfano	1 violations	Yes	0	A
173	Huerfano	1 violations	Yes	0	A
174	Le Chee	1 violations	Yes	3	A
175	Ojo Encino, North Of	1 violations	Yes	0	A-
176	Ojo Encino, North Of	1 violations	Yes	0	A-
177	Alpine	1 violations	Yes	5	B+
178	Aguila	1 violations	Yes	6	B+
179	Hard Rock, Dinnebeto, Rocky Ridge	1 violations	Yes	2	A
180	Ft. Wingate High School	1 violations	Yes	0	B
181	Ft. Wingate High School	1 violations	Yes	0	B
182	Fort Defiance	1 violations	Yes	1	F
183	Narbona Pass, Sheep Springs	1 violations	Yes	0	A
184	Narbona Pass, Sheep Springs	1 violations	Yes	0	A
185	Nazlini	1 violations	Yes	1	B
186	Circle City	1 violations	Yes	1	B+
187	Elfrida	1 violations	Yes	8	D
188	Iyanbito	1 violations	Yes	0	A
189	Iyanbito	1 violations	Yes	0	A
190	Nageezi	1 violations	Yes	2	A
191	Nageezi	1 violations	Yes	21	D+
192	Rock Point	1 violations	Yes	0	B-
193	Duncan	1 violations	Yes	8	F
194	Standing Rock	1 violations	Yes	0	A-
195	Standing Rock	1 violations	Yes	0	A-
196	Prescott Valley	1 violations	Yes	6	D
197	Crystal, Yazzie Springs, Crystal Junctio	1 violations	Yes	0	A-
198	Crystal, Yazzie Springs, Crystal Junctio	1 violations	Yes	0	A-
199	Shonto	1 violations	Yes	0	B+
200	Yarnell	1 violations	Yes	1	B+
201	Kayenta	1 violations	Yes	0	D

FAQ

Frequently asked questions about arsenic in Arizona

Is arsenic in Arizona tap water a concern?

Yes — 201 cities in Arizona have arsenic-related violations on record. The EPA MCL for arsenic is 10 µg/L. Even at levels below the MCL, long-term arsenic exposure has been linked to cancer and cardiovascular disease.

How can I remove arsenic from my drinking water in Arizona?

Reverse osmosis (RO) systems are the most effective at removing arsenic, typically reducing it by 90% or more. Specialized arsenic-removal media (such as iron-based adsorption filters) are also highly effective. Standard carbon filters and pitcher filters do NOT effectively remove arsenic. If your water comes from a private well, have it tested for arsenic.

Where does arsenic in Arizona water come from?

Arsenic enters drinking water primarily through natural erosion of arsenic-bearing rock formations. It is most common in groundwater systems in the western United States, parts of the Midwest, and New England. Industrial sources include mining, smelting, and agricultural pesticide residues. Groundwater sources are far more likely to contain arsenic than surface water.

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