Chromium-6 Contamination

Chromium-6 in Tennessee Drinking Water

Ranked by max chromium-6 detected (µg/L) · UCMR 3 data (2013–2015) · Data from EPA SDWIS & UCMR

109

Cities Tested

109

Detected

100%

% Detected

0.25 µg/L

State Avg

▼ 0% vs national

vs National

227

Health Violations

Analysis

Chromium-6 in Tennessee: what the data shows

Tennessee has 109 cities with chromium-6 data from the EPA's UCMR 3 program (2013–2015). Hexavalent chromium (Cr VI) was detected in 109 of those cities. There is currently no federal MCL for chromium-6 — California's 10 µg/L limit is used as a reference. The state average max detected level is 0.25 µg/L. Chromium-6 occurs naturally in some groundwater aquifers but also from industrial discharge, particularly from steel processing, chrome plating, and leather tanning. It is distinct from trivalent chromium (Cr III), which is an essential nutrient at low doses. The National Toxicology Program and IARC classify chromium-6 as a carcinogen via inhalation; the evidence for drinking water carcinogenicity is strong but regulatory action at the federal level remains pending as of 2026. Reverse osmosis systems effectively remove chromium-6 to near-undetectable levels.

Comparison

Cities exceeding No federal MCL (CA: 10 µg/L)

Tennessee

100%

109 of 109 cities

← = Exactly at national rate

National avg

100%

4005 of 4005 cities

City Map

Chromium-6 data across Tennessee

Each dot is a city with UCMR 3 chromium-6 data. Detected cities are shown; there is no federal MCL — California's 10 µg/L limit is used as a reference. Size reflects population served.

Worst Offenders

Top 10 cities by chromium-6 level in Tennessee

Highest Chromium-6 levels (µg/L)

All Cities

All Tennessee cities ranked by chromium-6 level

#	City	Level	Detected?	Violations	Grade
1	Cowan	1.50 µg/L	Detected	1	A-
2	Fayetteville	0.85 µg/L	Detected	2	D
3	Harvest	0.65 µg/L	Detected	1	B+
4	Harvest	0.65 µg/L	Detected	1	B+
5	Jacksboro	0.63 µg/L	Detected	7	D+
6	Elizabethton	0.62 µg/L	Detected	27	D
7	Springfield	0.58 µg/L	Detected	7	A
8	Cookeville	0.57 µg/L	Detected	4	B+
9	Cedar Hill	0.51 µg/L	Detected	1	A-
10	Cedar Hill	0.51 µg/L	Detected	1	A-
11	Etowah	0.50 µg/L	Detected	5	D+
12	Tellico Plains	0.50 µg/L	Detected	0	B-
13	Erwin	0.46 µg/L	Detected	27	A-
14	Lawrenceburg	0.45 µg/L	Detected	1	B+
15	Dandridge	0.42 µg/L	Detected	1	B+
16	Church Hill	0.41 µg/L	Detected	4	A-
17	Toone	0.39 µg/L	Detected	0	A-
18	Newport	0.39 µg/L	Detected	3	A
19	Maryville	0.37 µg/L	Detected	9	A-
20	Hixson	0.37 µg/L	Detected	0	A-
21	Union City	0.36 µg/L	Detected	0	A
22	Talbott	0.34 µg/L	Detected	0	A-
23	Soddy-Daisy	0.34 µg/L	Detected	2	A
24	Loudon	0.33 µg/L	Detected	5	B+
25	Morristown	0.32 µg/L	Detected	6	B
26	Cleveland	0.32 µg/L	Detected	58	B
27	Jackson	0.32 µg/L	Detected	0	A-
28	Germantown	0.32 µg/L	Detected	0	A-
29	Jonesborough	0.32 µg/L	Detected	12	A-
30	Dyersburg	0.32 µg/L	Detected	2	A
31	Georgetown	0.31 µg/L	Detected	2	B
32	Lenoir City	0.31 µg/L	Detected	3	B-
33	Decatur	0.29 µg/L	Detected	42	A
34	Bartlett	0.28 µg/L	Detected	0	A
35	Athens	0.27 µg/L	Detected	0	A
36	Russellville	0.27 µg/L	Detected	0	A+
37	Estill Springs	0.26 µg/L	Detected	66	B
38	Franklin	0.25 µg/L	Detected	25	C+
39	Dickson	0.24 µg/L	Detected	1	A
40	Gallatin	0.24 µg/L	Detected	1	A
41	Smithville	0.24 µg/L	Detected	6	C+
42	Pikeville	0.24 µg/L	Detected	51	B
43	Mcminnville	0.23 µg/L	Detected	8	B+
44	Murfreesboro	0.23 µg/L	Detected	4	B+
45	Clarksville	0.22 µg/L	Detected	8	B
46	Collierville	0.22 µg/L	Detected	2	A
47	Harriman	0.22 µg/L	Detected	13	D+
48	Nolensville	0.22 µg/L	Detected	8	B
49	Harriman	0.22 µg/L	Detected	1	B+
50	Sweetwater	0.22 µg/L	Detected	2	B
51	Lafayette	0.21 µg/L	Detected	3	A-
52	Hendersonville	0.20 µg/L	Detected	8	A-
53	Hendersonville	0.20 µg/L	Detected	4	A+
54	Smyrna	0.20 µg/L	Detected	9	A-
55	Kingsport	0.19 µg/L	Detected	6	B
56	Mount Juliet	0.19 µg/L	Detected	4	A+
57	Mount Juliet	0.19 µg/L	Detected	4	A+
58	Lewisburg	0.19 µg/L	Detected	3	B+
59	Columbia	0.18 µg/L	Detected	9	B+
60	Franklin	0.18 µg/L	Detected	12	B-
61	Morrison	0.18 µg/L	Detected	7	A
62	Johnson City	0.17 µg/L	Detected	0	A
63	Sevierville	0.17 µg/L	Detected	11	D
64	Portland	0.17 µg/L	Detected	5	A
65	Pleasant View	0.17 µg/L	Detected	0	A-
66	Clinton	0.17 µg/L	Detected	1	A
67	Nashville	0.17 µg/L	Detected	5	C+
68	Knoxville	0.16 µg/L	Detected	36	C-
69	Knoxville	0.16 µg/L	Detected	1	A
70	La Follette	0.15 µg/L	Detected	15	D+
71	La Follette	0.15 µg/L	Detected	15	D+
72	Pulaski	0.15 µg/L	Detected	4	B+
73	Brownsville	0.15 µg/L	Detected	0	A
74	Chattanooga	0.15 µg/L	Detected	25	C+
75	Greeneville	0.14 µg/L	Detected	50	C-
76	Lebanon	0.14 µg/L	Detected	21	C-
77	Martin	0.14 µg/L	Detected	0	A
78	Erin	0.14 µg/L	Detected	25	B+
79	Minor Hill	0.13 µg/L	Detected	31	C-
80	Bristol	0.12 µg/L	Detected	12	B-
81	Brentwood	0.12 µg/L	Detected	1	A-
82	Shelbyville	0.11 µg/L	Detected	28	C
83	Tullahoma	0.11 µg/L	Detected	0	B+
84	New Tazewell	0.11 µg/L	Detected	3	B+
85	Madisonville	0.11 µg/L	Detected	6	A-
86	Memphis	0.10 µg/L	Detected	4	C+
87	Madison	0.10 µg/L	Detected	1	A
88	Oak Ridge	0.10 µg/L	Detected	1	A-
89	Lexington	0.10 µg/L	Detected	11	A-
90	Dayton	0.10 µg/L	Detected	11	B-
91	Counce	0.10 µg/L	Detected	11	B
92	Lavergne	0.09 µg/L	Detected	9	B+
93	Winchester	0.09 µg/L	Detected	7	A-
94	Bethpage	0.09 µg/L	Detected	10	A
95	Lake City	0.08 µg/L	Detected	2	B-
96	Livingston	0.08 µg/L	Detected	10	A-
97	Blountville	0.08 µg/L	Detected	0	A+
98	Pigeon Forge	0.08 µg/L	Detected	1	A
99	Parsons	0.08 µg/L	Detected	15	C+
100	Alcoa	0.07 µg/L	Detected	4	A
101	Monteagle	0.07 µg/L	Detected	6	B
102	Spring Hill	0.06 µg/L	Detected	2	A-
103	Paris	0.06 µg/L	Detected	0	A-
104	Manchester	0.05 µg/L	Detected	2	D+
105	Oneida	0.05 µg/L	Detected	25	B+
106	Atoka	0.05 µg/L	Detected	5	A-
107	Crossville	0.04 µg/L	Detected	14	B+
108	Covington	0.04 µg/L	Detected	4	A
109	Jamestown	0.03 µg/L	Detected	21	B

FAQ

Frequently asked questions about chromium-6 in Tennessee

Is chromium-6 in Tennessee tap water dangerous?

Chromium-6 (hexavalent chromium) is a potential human carcinogen. There is currently no federal MCL — California's 10 µg/L limit is the most protective US standard. 109 cities in Tennessee had detectable chromium-6 in UCMR 3 testing (2013–2015). Reverse osmosis is the most effective removal method.

Where does chromium-6 come from in Tennessee water?

Chromium-6 enters water supplies from two main sources: natural weathering of chromium-containing rock formations (especially in the Southwest and parts of the Midwest) and industrial discharge from steel mills, chrome plating, and coal ash sites. Groundwater systems are more commonly affected by natural sources, while surface water systems near industrial areas face pollution-related risks.

How can I filter chromium-6 from my water in Tennessee?

Reverse osmosis (RO) systems are the most effective, removing over 95% of chromium-6. Some high-quality activated alumina or anion exchange filters also provide significant reduction. Standard carbon filters and pitcher filters are generally NOT effective against chromium-6. Look for filters certified by NSF International against NSF/ANSI 58 (for RO systems).

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