Manganese Contamination

Manganese in Minnesota Drinking Water

Ranked by max manganese detected (µg/L) · UCMR 4 data (2018–2020) · Data from EPA SDWIS & UCMR

Cities Tested

Over SMCL

27%

% Over SMCL

60.6 µg/L

State Avg

▲ 9% vs national

vs National

217

Health Violations

Analysis

Manganese in Minnesota: what the data shows

Minnesota has 93 cities with manganese data from the EPA's UCMR 4 program (2018–2020). Manganese exceeded the 50 µg/L EPA secondary MCL in 25 of those cities. The state average max detected level is 60.6 µg/L. Manganese occurs naturally in groundwater and surface water. Elevated levels are common in areas with iron-rich geology and in systems that draw from reservoirs with low dissolved oxygen. The secondary MCL of 50 µg/L is based on aesthetic concerns (taste, staining), but health-based guidelines suggest neurological effects at higher concentrations. Emerging research links chronic manganese exposure in drinking water to neurodevelopmental effects in children, including reduced IQ and behavioral issues. Oxidation filtration and water softeners are effective at removing manganese from household water.

Comparison

Cities exceeding 50 µg/L EPA Secondary MCL

Minnesota

27%

25 of 93 cities

→ ▲ 9% above national rate (worse)

National avg

18%

729 of 4068 cities

City Map

Manganese data across Minnesota

Each dot is a city with UCMR 4 manganese testing data. Cities where manganese exceeds the 50 µg/L EPA secondary MCL are highlighted. Size reflects population served.

Worst Offenders

Top 10 cities by manganese level in Minnesota

Highest Manganese levels (µg/L)

All Cities

All Minnesota cities ranked by manganese level

#	City	Level	Over SMCL?	Violations	Grade
1	Monticello	872.0 µg/L	Over SMCL	6	B
2	Chaska	602.0 µg/L	Over SMCL	2	B+
3	Lino Lakes	384.0 µg/L	Over SMCL	1	C+
4	Princeton	381.1 µg/L	Over SMCL	0	A-
5	Ramsey	365.0 µg/L	Over SMCL	0	A+
6	Northfield	344.0 µg/L	Over SMCL	0	A-
7	Bemidji	208.0 µg/L	Over SMCL	7	C
8	White Bear Lake	200.0 µg/L	Over SMCL	0	A-
9	Hugo	169.0 µg/L	Over SMCL	0	A+
10	Cloquet	167.0 µg/L	Over SMCL	0	A-
11	Rosemount	129.0 µg/L	Over SMCL	1	B+
12	St. Louis Park	115.0 µg/L	Over SMCL	5	A-
13	Minnetonka	86.6 µg/L	Over SMCL	0	A
14	Farmington	83.0 µg/L	Over SMCL	0	A-
15	Rochester	74.1 µg/L	Over SMCL	1	C+
16	Willmar	73.9 µg/L	Over SMCL	3	A-
17	Faribault	72.7 µg/L	Over SMCL	2	B+
18	Oakdale	72.6 µg/L	Over SMCL	1	B+
19	Edina	66.6 µg/L	Over SMCL	1	B+
20	South St. Paul	62.1 µg/L	Over SMCL	6	B+
21	Mounds View	60.9 µg/L	Over SMCL	0	A+
22	Cottage Grove	58.8 µg/L	Over SMCL	4	A-
23	Vadnais Heights	57.4 µg/L	Over SMCL	0	B+
24	Hopkins	55.7 µg/L	Over SMCL	0	B+
25	Shakopee	51.8 µg/L	Over SMCL	7	B
26	Oronoco	49.1 µg/L	No	0	A
27	Woodbury	42.3 µg/L	No	0	B+
28	Lake Benton	39.7 µg/L	No	1	A-
29	Hibbing	38.3 µg/L	No	1	C
30	Sauk Rapids	38.3 µg/L	No	2	B+
31	Burnsville	36.7 µg/L	No	0	A-
32	Blaine	35.9 µg/L	No	3	A-
33	North Mankato	33.9 µg/L	No	1	A-
34	Owatonna	31.3 µg/L	No	0	A
35	Albert Lea	29.1 µg/L	No	0	A-
36	Stillwater	28.9 µg/L	No	8	C+
37	North St. Paul	28.7 µg/L	No	1	A
38	Fridley	27.9 µg/L	No	0	A-
39	Robbinsdale	27.2 µg/L	No	0	A
40	Blackduck	25.1 µg/L	No	1	A-
41	Chanhassen	24.9 µg/L	No	0	B+
42	Hastings	19.3 µg/L	No	8	C+
43	Brooklyn Park	19.0 µg/L	No	0	B+
44	New Hope	18.0 µg/L	No	0	A-
45	Buffalo	17.1 µg/L	No	0	A-
46	Waconia	16.0 µg/L	No	0	B+
47	Marshall	15.9 µg/L	No	0	B+
48	St. Cloud	13.8 µg/L	No	2	A-
49	New Ulm	12.9 µg/L	No	0	B+
50	Sherburn	12.1 µg/L	No	0	A
51	Austin	11.8 µg/L	No	0	B+
52	Plymouth	11.7 µg/L	No	2	A-
53	Big Lake	10.6 µg/L	No	1	A
54	Forest Lake	10.6 µg/L	No	0	A
55	Coon Rapids	9.0 µg/L	No	2	A
56	Worthington	7.0 µg/L	No	0	B+
57	Maple Grove	6.4 µg/L	No	0	B+
58	Andover	5.9 µg/L	No	3	A+
59	Minneota	5.8 µg/L	No	0	A-
60	Anoka	4.9 µg/L	No	4	A
61	Cambridge	3.7 µg/L	No	0	A
62	Buhl	3.2 µg/L	No	2	A-
63	Champlin	3.1 µg/L	No	0	A
64	Brooklyn Center	3.0 µg/L	No	0	A
65	Golden Valley	2.8 µg/L	No	0	A-
66	Brainerd	2.6 µg/L	No	3	B+
67	Savage	2.4 µg/L	No	5	A-
68	Alexandria	2.4 µg/L	No	0	B
69	Lake City	2.3 µg/L	No	6	A
70	Lakeville	2.0 µg/L	No	2	A-
71	Crystal	2.0 µg/L	No	0	A+
72	Sartell	2.0 µg/L	No	0	A-
73	Columbia Heights	2.0 µg/L	No	0	B+
74	Hutchinson	1.7 µg/L	No	0	A
75	Eagan	1.7 µg/L	No	0	A-
76	Eden Prairie	1.5 µg/L	No	0	A-
77	Minneapolis	1.3 µg/L	No	2	B-
78	Bloomington	1.3 µg/L	No	1	A
79	St. Peter	1.2 µg/L	No	1	A+
80	Chisholm	1.2 µg/L	No	0	A-
81	Mankato	1.2 µg/L	No	8	F
82	Winona	1.2 µg/L	No	10	A
83	Prior Lake	1.1 µg/L	No	1	B+
84	Moorhead	1.1 µg/L	No	0	B+
85	Duluth	1.1 µg/L	No	1	A-
86	Roseville	1.0 µg/L	No	0	A
87	Elk River	0.8 µg/L	No	0	A
88	Apple Valley	0.7 µg/L	No	0	B+
89	Red Wing	0.7 µg/L	No	5	A
90	Shoreview	0.7 µg/L	No	0	A
91	Fergus Falls	0.6 µg/L	No	11	C
92	Inver Grove Heights	0.6 µg/L	No	37	D
93	Richfield	0.6 µg/L	No	0	A+

FAQ

Frequently asked questions about manganese in Minnesota

Is manganese in Minnesota tap water harmful?

The EPA secondary MCL for manganese is 50 µg/L, set primarily for aesthetic reasons (taste, color, staining). 25 cities in Minnesota exceed the secondary MCL. However, emerging research links chronic manganese exposure above 50–100 µg/L to neurodevelopmental effects in children, including reduced IQ.

How can I remove manganese from my drinking water?

Oxidation filtration (such as greensand or birm filters) is the most common and effective method for removing manganese from well water. Water softeners using ion exchange also work well. Standard carbon filters provide limited manganese removal. If your water has a metallic taste or brown/black discoloration, manganese may be the cause.

What causes high manganese in Minnesota water?

Manganese occurs naturally in groundwater and surface water, particularly in areas with iron-rich geology. Low dissolved oxygen conditions (common in deep wells and reservoir bottom waters) increase manganese solubility. Industrial sources include mining, steel production, and battery manufacturing. Seasonal changes in reservoir water chemistry can cause manganese spikes.

More contaminants