Water Quality Report · Updated May 12, 2026

CHARLESTON WATER SYSTEM (SC1010001)

Serving 327,422 residents in CHARLESTON, South Carolina .

National rank 24th percentile
South Carolina rank 14th percentile
Data confidence Medium
D
55/100
Below Average
ⓘ How did we get this rating?
Quick answer

CHARLESTON WATER SYSTEM (SC1010001) delivers tap water graded D (55/100) by TapWaterSafety.org. The utility serves approximately 327,422 residents in CHARLESTON, South Carolina using surface water. 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. For questions, the utility can be reached at 843-863-4038.

Data sources for this grade: utilities.csv EWG Tap Water Database ⓘ How did we get this rating?
327,422
People served
1
City served
25
Contaminants detected
12
Above health guidelines
0
EPA violations (5 yr)

Is CHARLESTON tap water safe to drink?

CHARLESTON WATER SYSTEM (SC1010001) delivers tap water that earns a grade of D (55/100) from TapWaterSafety.org — a below-average rating, with multiple concerns including pfas contamination.

The utility serves 327,422 residents in CHARLESTON, drawing from surface water.

Public testing data identifies 12 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA9), Haloacetic acids (HAA5), Dibromoacetic acid, Total trihalomethanes (TTHMs), Bromodichloromethane, Dichloroacetic acid, Dibromochloromethane, Chloroform, Perfluorooctanoic acid (PFOA), Perfluorooctane sulfonate (PFOS), Trichloroacetic acid, Chromium (hexavalent). For most residents, a properly certified home filter at the kitchen tap is the most cost-effective way to reduce exposure to whatever's in your water. See our filter recommendations below, matched specifically to this utility's contaminant profile.

Top concerns in this water

Based on the most recent EPA and EWG data, these are the most significant water quality issues for CHARLESTON WATER SYSTEM (SC1010001).

PFAS contamination

Severe concern

Perfluorooctane 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 concern

Haloacetic 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 concern

Haloacetic acids (HAA5) detected at 11.4 ppb, 114x above the EWG health guideline of 0.1 ppb.

Dibromoacetic acid significantly above health guideline

Moderate concern

Dibromoacetic acid detected at 1.73 ppb, 58x above the EWG health guideline of 0.03 ppb.

Contact CHARLESTON WATER SYSTEM (SC1010001)

Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.

Recommended water filters for CHARLESTON

Filters matched to the specific contaminants in this water supply.

Reverse Osmosis or NSF P473 certified carbon

$80-$750

Activated carbon and RO are the only technologies proven to remove PFAS at certified levels.

AquaTru Countertop Reverse Osmosis
$449-$599 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Aquasana OptimH2O Reverse Osmosis + Claryum
$429-$549 NSF 42, 53, 58, 401, P473
Editorial pick · affiliate link coming soon
Waterdrop G3P800 Tankless RO
$600-$750 NSF 58, 372
View on retailer →
Waterdrop N1 Countertop RO
$249-$329 NSF 58, 372
View on retailer →
Clearly Filtered Pitcher Filter
$80-$95 NSF 42, 53, 401, P473
Editorial pick · affiliate link coming soon

Disclosure: TapWaterSafety earns a commission from purchases made through these links. This does not influence our scoring methodology or filter selection.

Score breakdown

This utility's overall score of 55/100 breaks down across five weighted components. Read the full methodology →

Health Guideline Performance
10 / 40
Legal Compliance
20 / 20
High-Risk Contaminants
8 / 20
Compliance History
10 / 10
Source Water Vulnerability
7 / 10

Contaminants detected — international standards comparison

Every contaminant detected, compared side-by-side against US EPA legal limits, the EU Drinking Water Directive (2020/2184), WHO Guidelines, and California's Public Health Goal (the strictest US benchmark). 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 (4th ed.), California OEHHA PHGs, EWG Tap Water Database.

CHARLESTON WATER SYSTEM (SC1010001) service area

This water system serves 1 community in Charleston County, South Carolina. Click any city for its dedicated tap water quality page.

About this water system

Public Water System ID
SC1010001
Owner type
Local government
Source water
Surface water
Service connections
146,569
Service area
CHARLESTON, Charleston County, South Carolina