Tap Water Quality Report
Tap water quality in CHARLESTON, South Carolina
Tap water in CHARLESTON, South Carolina receives a grade of D (68/100) from TapWaterSafety.org. It's served by CHARLESTON WATER SYSTEM (SC1010001). The most significant water quality concerns are: PFAS contamination; Haloacetic acids (HAA9) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline; Dibromoacetic acid significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in CHARLESTON's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving CHARLESTON.
PFAS contamination
Severe concernPerfluorooctane sulfonate (PFOS), Perfluorooctanoic acid (PFOA) detected. PFAS are persistent chemicals linked to cancer and immune effects with no known safe exposure threshold.
Haloacetic acids (HAA9) significantly above health guideline
Moderate concernHaloacetic acids (HAA9) detected at 16.7 ppb, 278x above the EWG health guideline of 0.06 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 11.4 ppb, 114x above the EWG health guideline of 0.1 ppb.
Dibromoacetic acid significantly above health guideline
Moderate concernDibromoacetic acid detected at 1.73 ppb, 58x above the EWG health guideline of 0.03 ppb.
EPA compliance record
Official U.S. EPA records for CHARLESTON WATER SYSTEM (SC1010001) (system ID SC1010001) for the last 3 years. Checked 2026-10-07.
Source: U.S. EPA Enforcement and Compliance History Online (ECHO), from the Safe Drinking Water Information System. See EPA's full report.
Recommended filters for CHARLESTON
Filters matched to the specific contaminants in CHARLESTON's water supply.
Filter certified for PFOA/PFOS (NSF/ANSI 53 or 58)
$180-$750Reverse osmosis and some carbon block filters reduce PFAS. Look for certification to NSF/ANSI 53 or 58 for PFOA/PFOS.
Carbon filter certified for VOCs (NSF/ANSI 53)
$180-$599Activated carbon is effective for disinfection byproducts. Look for NSF/ANSI 53 VOC reduction.
Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.
All contaminants detected in CHARLESTON's tap water
Every contaminant identified, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal. Why we show multiple standards →
| Contaminant | Detected | EWG US health-based |
EPA US legal |
EU DWD Europe |
WHO global |
CA PHG strictest US |
Tested sample year |
Status |
|---|---|---|---|---|---|---|---|---|
| Haloacetic acids (HAA9) Disinfection byproduct |
16.7 ppb | 0.06 | — | — | — | — | — | 278× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
11.4 ppb | 0.1 | 60.0 | 60 | — | — | — | 114× over |
| Dibromoacetic acid Disinfection byproduct |
1.73 ppb | 0.03 | — | — | — | — | — | 58× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
8.43 ppb | 0.15 | 80.0 | 100 | — | — | — | 56× over |
| Bromodichloromethane Disinfection byproduct |
2.84 ppb | 0.06 | — | — | — | — | — | 47× over |
| Dichloroacetic acid Disinfection byproduct |
8.99 ppb | 0.2 | — | — | — | — | — | 45× over |
| Dibromochloromethane Disinfection byproduct |
1.59 ppb | 0.1 | — | — | — | — | — | 16× over |
| Chloroform Disinfection byproduct |
4.0 ppb | 0.4 | — | — | — | — | — | 10× over |
| Perfluorooctanoic acid (PFOA) PFAS |
0.76 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | 8.4× over |
| Perfluorooctane sulfonate (PFOS) PFAS |
1.5 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | 5.0× over |
| Trichloroacetic acid Disinfection byproduct |
0.461 ppb | 0.1 | — | — | — | — | — | 4.6× over |
| Chromium (hexavalent) Heavy metal |
0.0623 ppb | 0.02 | — | — | — | — | — | 3.1× over |
| Chlorate Disinfection byproduct |
183.8 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Nitrate Inorganic |
0.102 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | Below guideline |
| 1,4-Dioxane Semi-volatile organic compound |
0.15 ppb | 0.35 | — | — | 50 | 1 | — | Below guideline |
| Manganese Heavy metal |
9.34 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Vanadium Other |
0.93 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
5.0 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
0.232 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
4.3 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| 2,4-D Pesticide/Herbicide |
0.04 ppb | 20.0 | 70.0 | — | — | — | — | Below guideline |
| Perfluoroheptanoic acid (PFHPA) PFAS |
0.4 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
0.58 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.0535 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.17 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
All values in the unit of the detected level. Red cells indicate the detected level exceeds that standard. Some contaminants have limits in some jurisdictions but not others (shown as —). The "Tested" column shows the year each contaminant sample was collected.
Sources: US EPA, EU Drinking Water Directive 2020/2184, WHO Guidelines, California OEHHA PHGs, EWG Tap Water Database.
Treatment plant contact info
For service issues, water quality concerns, or to request a Consumer Confidence Report from CHARLESTON WATER SYSTEM (SC1010001).