Arsenic Contamination

Arsenic in Oklahoma Drinking Water

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

Cities Tested

Has Violations

100%

% Has Violations

4.3 violations

State Avg

▼ 0% vs national

vs National

351

Health Violations

Analysis

Arsenic in Oklahoma: what the data shows

Oklahoma has 71 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 71 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

Oklahoma

100%

71 of 71 cities

← = Exactly at national rate

National avg

100%

5489 of 5489 cities

City Map

Arsenic data across Oklahoma

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 Oklahoma

Highest Arsenic levels (violations)

All Cities

All Oklahoma cities ranked by arsenic level

#	City	Level	Violations?	Violations	Grade
1	Weatherford	54 violations	Yes	71	D
2	Hinton	34 violations	Yes	47	D+
3	Walters	31 violations	Yes	104	D+
4	Edmond	17 violations	Yes	86	F
5	Corn	15 violations	Yes	14	B
6	Moore	12 violations	Yes	53	F
7	Noble	10 violations	Yes	160	D
8	Norman	9 violations	Yes	52	F
9	Ninnekah	8 violations	Yes	9	B+
10	Shidler	7 violations	Yes	145	D
11	Mustang	6 violations	Yes	9	C+
12	Oklahoma City	5 violations	Yes	56	F
13	Tuttle	5 violations	Yes	46	D
14	Yukon	4 violations	Yes	18	D
15	Cookson	4 violations	Yes	102	D
16	Goodwell	4 violations	Yes	15	C+
17	Tecumseh	3 violations	Yes	142	F
18	Nichols Hills	3 violations	Yes	21	D
19	Mcloud	3 violations	Yes	14	D
20	Fairland	3 violations	Yes	11	D
21	Laverne	3 violations	Yes	3	C
22	Washington	3 violations	Yes	8	C
23	Chickasha	2 violations	Yes	79	F
24	Miami	2 violations	Yes	11	D
25	Grove	2 violations	Yes	20	D
26	Seminole	2 violations	Yes	4	A
27	Earlsboro	2 violations	Yes	4	C+
28	Elgin	2 violations	Yes	13	D+
29	Harrah	2 violations	Yes	61	D
30	Bristow	2 violations	Yes	5	D
31	Fairview	2 violations	Yes	97	D
32	Vian	2 violations	Yes	7	D+
33	Wellston	2 violations	Yes	71	F
34	Buffalo	2 violations	Yes	16	D+
35	Stuart	2 violations	Yes	96	C-
36	Osage	2 violations	Yes	21	D+
37	Sapulpa	1 violations	Yes	85	D
38	Durant	1 violations	Yes	104	D
39	Madill	1 violations	Yes	178	F
40	Guthrie	1 violations	Yes	45	F
41	Woodward	1 violations	Yes	55	D
42	Skiatook	1 violations	Yes	72	B-
43	Mounds	1 violations	Yes	219	D+
44	Henryetta	1 violations	Yes	116	F
45	Ochelata	1 violations	Yes	41	D
46	Hulbert	1 violations	Yes	117	D
47	Fort Gibson	1 violations	Yes	153	F
48	Piedmont	1 violations	Yes	32	C-
49	Kellyville	1 violations	Yes	32	B-
50	Locust Grove	1 violations	Yes	103	D
51	Quinton	1 violations	Yes	42	D
52	Big Cabin	1 violations	Yes	39	D+
53	Pawnee	1 violations	Yes	276	D
54	Jay	1 violations	Yes	87	D
55	Pawhuska	1 violations	Yes	34	D+
56	Chandler	1 violations	Yes	150	D
57	Afton	1 violations	Yes	89	F
58	Cordell	1 violations	Yes	46	C+
59	Bowlegs	1 violations	Yes	9	B+
60	Prague	1 violations	Yes	10	D+
61	Crowder	1 violations	Yes	91	C+
62	Wyandotte	1 violations	Yes	5	D
63	Chelsea	1 violations	Yes	10	A-
64	Terlton	1 violations	Yes	50	D+
65	Mooreland	1 violations	Yes	59	D+
66	Quapaw	1 violations	Yes	9	D
67	Cheyenne	1 violations	Yes	64	D
68	Velma	1 violations	Yes	1	B+
69	Kiowa	1 violations	Yes	197	D
70	Bokchito	1 violations	Yes	4	A
71	Achille	1 violations	Yes	2	A-

FAQ

Frequently asked questions about arsenic in Oklahoma

Is arsenic in Oklahoma tap water a concern?

Yes — 71 cities in Oklahoma 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 Oklahoma?

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 Oklahoma 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.

More contaminants