Manganese Contamination

Manganese in Arkansas Drinking Water

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

Cities Tested

Over SMCL

% Over SMCL

23.1 µg/L

State Avg

▼ 10% vs national

vs National

311

Health Violations

Analysis

Manganese in Arkansas: what the data shows

Arkansas has 59 cities with manganese data from the EPA's UCMR 4 program (2018–2020). Manganese exceeded the 50 µg/L EPA secondary MCL in 5 of those cities. The state average max detected level is 23.1 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

Arkansas

5 of 59 cities

← ▼ 10% below national rate (better)

National avg

18%

729 of 4068 cities

City Map

Manganese data across Arkansas

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 Arkansas

Highest Manganese levels (µg/L)

All Cities

All Arkansas cities ranked by manganese level

#	City	Level	Over SMCL?	Violations	Grade
1	Swifton	350.0 µg/L	Over SMCL	17	C-
2	Camden	268.0 µg/L	Over SMCL	126	D
3	Prairie Grove	200.0 µg/L	Over SMCL	11	A-
4	Stuttgart	66.4 µg/L	Over SMCL	15	A-
5	Heber Springs	61.0 µg/L	Over SMCL	2	A
6	Hope	36.3 µg/L	No	57	F
7	Paragould	33.6 µg/L	No	6	A
8	Malvern	30.5 µg/L	No	19	B+
9	Texarkana	28.6 µg/L	No	25	B+
10	Searcy	28.4 µg/L	No	2	A-
11	Magnolia	22.0 µg/L	No	32	C+
12	Arkadelphia	21.1 µg/L	No	5	B+
13	Russelville	17.2 µg/L	No	11	A-
14	West Memphis	16.3 µg/L	No	12	A
15	Hot Springs	16.1 µg/L	No	43	B+
16	Dardanelle	13.0 µg/L	No	36	C+
17	Poplar Grove	13.0 µg/L	No	2	A+
18	Morrilton	11.2 µg/L	No	7	B+
19	El Dorado	11.0 µg/L	No	77	D
20	Bryant	7.0 µg/L	No	6	A+
21	Blytheville	6.7 µg/L	No	8	C
22	Greers Ferry	6.3 µg/L	No	6	A
23	Little Rock	6.2 µg/L	No	44	C+
24	Jacksonville	6.2 µg/L	No	7	A+
25	Batesville	5.9 µg/L	No	65	D+
26	Mabelvale	5.9 µg/L	No	0	A-
27	Forrest City	5.9 µg/L	No	4	A
28	Ash Flat	4.8 µg/L	No	1	A-
29	Pine Bluff	4.3 µg/L	No	5	A-
30	Cabot	4.3 µg/L	No	6	A
31	Grannis	3.9 µg/L	No	0	A
32	Conway	3.7 µg/L	No	14	B
33	Benton	3.5 µg/L	No	10	A
34	Jonesboro	3.1 µg/L	No	2	A+
35	Piggott	3.1 µg/L	No	29	C+
36	Farmington	2.8 µg/L	No	15	B+
37	Des Arc	2.7 µg/L	No	11	A-
38	Junction City	2.5 µg/L	No	53	D
39	Rogers	2.3 µg/L	No	17	B-
40	Bella Vista	2.2 µg/L	No	13	B+
41	Greenwood	2.2 µg/L	No	93	D+
42	Austin	2.0 µg/L	No	1	B
43	Russellville	1.8 µg/L	No	25	C-
44	Van Buren	1.8 µg/L	No	16	C+
45	Tumbling Shoals	1.8 µg/L	No	1	A-
46	Centerton	1.7 µg/L	No	4	A
47	Bald Knob	1.7 µg/L	No	11	A-
48	Vilonia	1.5 µg/L	No	2	A
49	Bentonville	1.4 µg/L	No	2	A-
50	Redfield	1.3 µg/L	No	1	A-
51	Harrison	1.2 µg/L	No	14	B+
52	Fayetteville	1.1 µg/L	No	17	D
53	Fort Smith	1.1 µg/L	No	19	D
54	Monticello	1.1 µg/L	No	31	C-
55	Springdale	1.0 µg/L	No	2	B
56	Siloam Springs	1.0 µg/L	No	49	F
57	Marion	0.9 µg/L	No	11	C
58	Mountain Home	0.8 µg/L	No	22	B+
59	Hot Springs Village	0.7 µg/L	No	0	A+

FAQ

Frequently asked questions about manganese in Arkansas

Is manganese in Arkansas tap water harmful?

The EPA secondary MCL for manganese is 50 µg/L, set primarily for aesthetic reasons (taste, color, staining). 5 cities in Arkansas 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 Arkansas 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.

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