HAA5 Contamination

HAA5 in South Carolina Drinking Water

Ranked by average HAA5 concentration (µg/L) · UCMR 4 data (2018–2020) · Data from EPA SDWIS & UCMR

Cities Tested

Exceeds Limit

% Exceeds Limit

17.2 µg/L

State Avg

▼ 1% vs national

vs National

151

Health Violations

Analysis

HAA5 in South Carolina: what the data shows

South Carolina has 68 cities with HAA5 monitoring data from the EPA's UCMR 4 program (2018–2020). Haloacetic acids (HAA5) form when chlorine-based disinfectants react with natural organic matter in water. The state average is 17.2 µg/L — better than the 15.5 µg/L national average. No cities currently exceed the 60 µg/L EPA MCL. HAA5 is a group of five chlorinated and brominated acetic acids. Long-term exposure above the MCL is associated with increased cancer risk and adverse reproductive outcomes. The EPA classifies total HAA5 as a probable human carcinogen at elevated concentrations. Activated carbon filtration (especially granular or block carbon) is effective at reducing HAA5. Running water through a refrigerator filter or letting it sit in an open pitcher for 30 minutes also helps, as some HAA5 species are volatile. Boiling does not remove disinfection byproducts and may concentrate them.

Comparison

Cities exceeding 60 µg/L EPA MCL

South Carolina

0 of 68 cities

← ▼ 1% below national rate (better)

National avg

23 of 4420 cities

City Map

HAA5 data across South Carolina

Each dot is a city with UCMR 4 HAA5 testing data. Cities where average HAA5 exceeded the 60 µg/L EPA MCL are highlighted. Size reflects population served.

Worst Offenders

Top 10 cities by haa5 level in South Carolina

Highest HAA5 levels (µg/L)

All Cities

All South Carolina cities ranked by haa5 level

#	City	Level	Exceeds?	Violations	Grade
1	Orangeburg	57.2 µg/L	No	3	A-
2	Okatie	41.1 µg/L	No	7	B+
3	Cayce	39.0 µg/L	No	2	A-
4	Walhalla	39.0 µg/L	No	1	A-
5	Newberry	34.8 µg/L	No	28	C
6	Woodruff	34.6 µg/L	No	5	A-
7	North Augusta	34.0 µg/L	No	13	B+
8	Gaffney	31.1 µg/L	No	12	C+
9	Pickens	30.8 µg/L	No	7	B+
10	Inman	30.4 µg/L	No	1	A
11	Columbia	29.2 µg/L	No	80	F
12	Lyman	28.6 µg/L	No	2	A+
13	Conway	26.9 µg/L	No	14	C+
14	Pawleys Island	26.9 µg/L	No	13	B-
15	Fort Jackson	26.8 µg/L	No	8	A-
16	Laurens	26.6 µg/L	No	17	B-
17	Easley	24.5 µg/L	No	2	B+
18	Lugoff	24.4 µg/L	No	13	B+
19	Donalds	24.2 µg/L	No	3	B+
20	Landrum	24.1 µg/L	No	3	A-
21	Spartanburg	22.0 µg/L	No	2	A
22	Greer	21.8 µg/L	No	3	A
23	Seneca	20.4 µg/L	No	0	A
24	Myrtle Beach	19.8 µg/L	No	17	B-
25	North Myrtle Beach	19.1 µg/L	No	4	B+
26	La France	18.4 µg/L	No	0	A-
27	Union	18.4 µg/L	No	14	B+
28	Greenwood	17.6 µg/L	No	14	C
29	West Columbia	17.6 µg/L	No	87	F
30	Rock Hill	17.3 µg/L	No	45	F
31	Graniteville	16.9 µg/L	No	3	A-
32	Fort Lawn	16.6 µg/L	No	7	B+
33	Belton	16.5 µg/L	No	13	B
34	West Anderson	16.4 µg/L	No	1	A
35	Chesnee	16.1 µg/L	No	0	A-
36	Lexington	16.0 µg/L	No	55	F
37	Summerville	15.6 µg/L	No	22	C+
38	Aiken	14.8 µg/L	No	11	D
39	Camden	14.7 µg/L	No	7	B+
40	North Charleston	14.0 µg/L	No	0	B
41	Westminster	14.0 µg/L	No	8	C-
42	Clemson	13.3 µg/L	No	4	B+
43	Goose Creek	13.0 µg/L	No	0	B+
44	York	12.6 µg/L	No	65	F
45	Fort Mill	12.2 µg/L	No	26	B-
46	Charleston	11.3 µg/L	No	5	B+
47	Moncks Corner	10.9 µg/L	No	6	B-
48	Lancaster	10.7 µg/L	No	33	B+
49	Florence	10.7 µg/L	No	3	B+
50	Santee	9.9 µg/L	No	2	B-
51	Anderson	9.8 µg/L	No	15	C+
52	Johns Island (Sta.)	9.5 µg/L	No	1	A-
53	Six Mile	9.4 µg/L	No	1	A+
54	Mount Pleasant	8.4 µg/L	No	1	B+
55	Greenville	8.1 µg/L	No	9	A
56	Marion	6.8 µg/L	No	4	A
57	Hilton Head Island	6.4 µg/L	No	4	B-
58	Lake City	3.4 µg/L	No	0	A+
59	Dillon	2.7 µg/L	No	2	A
60	Yemassee	1.1 µg/L	No	0	A
61	Sumter	0.4 µg/L	No	15	D
62	Walterboro	0.4 µg/L	No	0	A+
63	Cassatt	0.4 µg/L	No	4	A
64	Dalzell	0.3 µg/L	No	7	B-
65	St. George	0.3 µg/L	No	0	A-
66	Darlington	0.2 µg/L	No	6	B+
67	Chesterfield	0.1 µg/L	No	10	A-
68	Beech Island	0.0 µg/L	No	0	B+

FAQ

Frequently asked questions about haa5 in South Carolina

What is HAA5 and why does it appear in South Carolina tap water?

HAA5 (haloacetic acids) are disinfection byproducts that form when chlorine reacts with naturally occurring organic matter in source water. They are a normal byproduct of the disinfection process that makes water safe to drink. No cities in South Carolina currently exceed the 60 µg/L EPA MCL. The state average is 17.2 µg/L.

How can I reduce HAA5 exposure from South Carolina drinking water?

Activated carbon filters (granular or block) effectively reduce HAA5. Refrigerator filters and under-sink carbon systems are convenient options. Unlike lead or PFAS, HAA5 levels can also be reduced by letting water stand in an open container, as some species evaporate. Boiling does NOT remove HAA5 and can concentrate them by reducing water volume.

Which South Carolina cities have the highest HAA5 levels?

The cities with the highest average HAA5 concentrations in South Carolina are: Orangeburg (57.2 µg/L), Okatie (41.1 µg/L), Cayce (39.0 µg/L), Walhalla (39.0 µg/L), Newberry (34.8 µg/L). Note: this data is from UCMR 4 testing (2018–2020) and may not reflect current levels.

More contaminants