Arsenic Contamination

Arsenic in Oregon Drinking Water

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

154

Cities Tested

154

Has Violations

100%

% Has Violations

7.4 violations

State Avg

▼ 0% vs national

vs National

205

Health Violations

Analysis

Arsenic in Oregon: what the data shows

Oregon has 154 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 154 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

Oregon

100%

154 of 154 cities

← = Exactly at national rate

National avg

100%

5489 of 5489 cities

City Map

Arsenic data across Oregon

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 Oregon

Highest Arsenic levels (violations)

All Cities

All Oregon cities ranked by arsenic level

#	City	Level	Violations?	Violations	Grade
1	Eugene	105 violations	Yes	178	F
2	Vale	52 violations	Yes	45	C
3	Scappoose	47 violations	Yes	84	F
4	Woodburn	46 violations	Yes	50	F
5	Shady Cove	45 violations	Yes	56	D
6	Hubbard	43 violations	Yes	30	F
7	Portland	41 violations	Yes	118	F
8	Warm Springs	38 violations	Yes	89	F
9	Newberg	36 violations	Yes	270	F
10	Salem	34 violations	Yes	108	F
11	Rainier	31 violations	Yes	121	D
12	Nyssa	29 violations	Yes	34	B-
13	Grants Pass	26 violations	Yes	78	F
14	Clackamas	23 violations	Yes	21	D
15	Central Point	22 violations	Yes	68	D
16	Molalla	22 violations	Yes	75	F
17	Newport	19 violations	Yes	29	F
18	Clatskanie	19 violations	Yes	57	D
19	Cottage Grove	18 violations	Yes	173	F
20	Terrebonne	18 violations	Yes	28	D
21	St Helens	16 violations	Yes	33	F
22	Aurora	13 violations	Yes	19	D+
23	Creswell	12 violations	Yes	13	C+
24	Bandon	12 violations	Yes	119	F
25	Prineville	11 violations	Yes	56	F
26	Hermiston	10 violations	Yes	67	F
27	Bend	9 violations	Yes	116	F
28	Albany	9 violations	Yes	35	F
29	Roseburg	9 violations	Yes	35	F
30	Redmond	9 violations	Yes	35	D
31	Seaside	9 violations	Yes	27	F
32	Malin	9 violations	Yes	9	B
33	Klamath Falls	8 violations	Yes	36	F
34	Ashland	8 violations	Yes	15	D
35	Sandy	8 violations	Yes	161	F
36	Cave Junction	8 violations	Yes	60	D
37	Corvallis	7 violations	Yes	38	F
38	Tillamook	6 violations	Yes	38	F
39	Amity	6 violations	Yes	31	D
40	Burns	6 violations	Yes	19	D+
41	Riddle	6 violations	Yes	55	F
42	The Dalles	5 violations	Yes	54	F
43	Astoria	5 violations	Yes	45	F
44	Sisters	5 violations	Yes	12	C
45	Boring	5 violations	Yes	39	D+
46	Gold Beach	5 violations	Yes	3	F
47	Vernonia	5 violations	Yes	11	D
48	Westport	5 violations	Yes	32	D+
49	Medford	4 violations	Yes	44	F
50	Hillsboro	4 violations	Yes	7	F
51	Springfield	4 violations	Yes	19	F
52	West Linn	4 violations	Yes	15	F
53	Canby	4 violations	Yes	21	D
54	Brookings	4 violations	Yes	19	D
55	Wamic	4 violations	Yes	10	C-
56	Tangent	4 violations	Yes	7	C
57	Beaverton	3 violations	Yes	10	F
58	Tigard	3 violations	Yes	3	C
59	Happy Valley	3 violations	Yes	17	F
60	Keizer	3 violations	Yes	7	C
61	Ontario	3 violations	Yes	5	B-
62	La Grande	3 violations	Yes	7	B-
63	Fairview	3 violations	Yes	20	D
64	Baker City	3 violations	Yes	4	C+
65	Estacada	3 violations	Yes	119	F
66	Waldport	3 violations	Yes	25	D
67	Reedsport	3 violations	Yes	8	C-
68	Corbett	3 violations	Yes	10	C-
69	Banks	3 violations	Yes	5	B+
70	Willamina	3 violations	Yes	4	A-
71	Lyons	3 violations	Yes	8	F
72	Welches	3 violations	Yes	47	D+
73	Glide	3 violations	Yes	1	B+
74	Port Orford	3 violations	Yes	24	D
75	Oakland	3 violations	Yes	2	D+
76	Otis	3 violations	Yes	28	D
77	Adair Village	3 violations	Yes	12	C
78	Oceanside	3 violations	Yes	6	C
79	Milwaukie	2 violations	Yes	1	F
80	Lake Oswego	2 violations	Yes	20	D
81	Lincoln City	2 violations	Yes	1	B+
82	Lebanon	2 violations	Yes	16	F
83	Silverton	2 violations	Yes	18	C
84	Winston	2 violations	Yes	9	B
85	Sheridan	2 violations	Yes	5	D
86	Milton-Freewater	2 violations	Yes	12	F
87	Myrtle Creek	2 violations	Yes	55	D+
88	Talent	2 violations	Yes	3	B-
89	Coquille	2 violations	Yes	57	F
90	Lafayette	2 violations	Yes	16	C-
91	Toledo	2 violations	Yes	0	A
92	Jefferson	2 violations	Yes	4	C+
93	Nehalem	2 violations	Yes	8	D
94	Brownsville	2 violations	Yes	17	F
95	Stanfield	2 violations	Yes	4	C
96	Mill City	2 violations	Yes	0	A
97	Colton	2 violations	Yes	23	D+
98	Ophir	2 violations	Yes	2	B-
99	Gold Hill	2 violations	Yes	17	D
100	Pendelton	2 violations	Yes	1	D+
101	Falls City	2 violations	Yes	3	B-
102	Pacific City	2 violations	Yes	2	D
103	Cloverdale	2 violations	Yes	5	F
104	Antelope	2 violations	Yes	25	C-
105	Mcminnville	1 violations	Yes	1	B+
106	Forest Grove	1 violations	Yes	2	B+
107	Wilsonville	1 violations	Yes	10	C+
108	Dallas	1 violations	Yes	4	B-
109	Pendleton	1 violations	Yes	43	F
110	Troutdale	1 violations	Yes	2	A-
111	Hood River	1 violations	Yes	13	D+
112	Cornelius	1 violations	Yes	5	F
113	Florence	1 violations	Yes	6	A-
114	Independence	1 violations	Yes	6	B
115	Sweet Home	1 violations	Yes	83	B-
116	Eagle Point	1 violations	Yes	1	C+
117	Warrenton	1 violations	Yes	2	B+
118	Sutherlin	1 violations	Yes	6	B
119	Boardman	1 violations	Yes	0	C+
120	Gleneden Beach	1 violations	Yes	2	A-
121	Philomath	1 violations	Yes	35	B+
122	Gaston	1 violations	Yes	13	D
123	Jacksonville	1 violations	Yes	10	C+
124	Harbor	1 violations	Yes	3	B+
125	Enterprise	1 violations	Yes	24	D+
126	Myrtle Point	1 violations	Yes	9	D+
127	Grand Ronde	1 violations	Yes	22	D+
128	Dayton	1 violations	Yes	5	A-
129	Rogue River	1 violations	Yes	7	C
130	Lakeview	1 violations	Yes	2	D
131	Carlton	1 violations	Yes	9	B-
132	Yamhill	1 violations	Yes	53	F
133	Lakeside	1 violations	Yes	2	A
134	Neskowin	1 violations	Yes	3	B
135	Cannon Beach	1 violations	Yes	3	C+
136	Rickreall	1 violations	Yes	15	F
137	Bay City	1 violations	Yes	3	B
138	Rockaway Beach	1 violations	Yes	15	A-
139	Chiloquin	1 violations	Yes	8	D+
140	Coburg	1 violations	Yes	6	B+
141	Donald	1 violations	Yes	14	A
142	Yoncalla	1 violations	Yes	44	C
143	Yachats	1 violations	Yes	5	D
144	Rhododendron	1 violations	Yes	4	B
145	Christmas Valley	1 violations	Yes	3	A
146	Scio	1 violations	Yes	4	C
147	Prairie City	1 violations	Yes	6	B-
148	Mulino	1 violations	Yes	10	F
149	Condon	1 violations	Yes	1	B+
150	Powers	1 violations	Yes	14	B+
151	Dufur	1 violations	Yes	4	C-
152	Mapleton	1 violations	Yes	70	D
153	Maupin	1 violations	Yes	12	D
154	Mount Vernon	1 violations	Yes	3	B+

FAQ

Frequently asked questions about arsenic in Oregon

Is arsenic in Oregon tap water a concern?

Yes — 154 cities in Oregon 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 Oregon?

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 Oregon 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