Tap Water Quality Report
Tap water quality in ROCK HILL, South Carolina
Tap water in ROCK HILL, South Carolina receives a grade of D (64/100) from TapWaterSafety.org. It's served by ROCK HILL CITY OF (SC4610002). The most significant water quality concerns are: PFAS contamination; Haloacetic acids (HAA9) significantly above health guideline; Total trihalomethanes (TTHMs) significantly above health guideline; Haloacetic acids (HAA5) significantly above health guideline. Data sources: EPA SDWIS, EPA ECHO, EWG Tap Water Database.
What's in ROCK HILL's tap water
Top water quality concerns identified by the EPA and Environmental Working Group across the utility serving ROCK HILL.
PFAS contamination
Severe concernPerfluorooctanoic acid (PFOA), Perfluorooctane sulfonate (PFOS) 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 24.3 ppb, 405x above the EWG health guideline of 0.06 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 35.4 ppb, 236x above the EWG health guideline of 0.15 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 16.0 ppb, 160x above the EWG health guideline of 0.1 ppb.
EPA compliance record
Official U.S. EPA records for ROCK HILL CITY OF (SC4610002) (system ID SC4610002) 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 ROCK HILL
Filters matched to the specific contaminants in ROCK HILL'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 ROCK HILL'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 |
24.3 ppb | 0.06 | — | — | — | — | — | 405× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
35.4 ppb | 0.15 | 80.0 | 100 | — | — | — | 236× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
16.0 ppb | 0.1 | 60.0 | 60 | — | — | — | 160× over |
| Bromodichloromethane Disinfection byproduct |
9.34 ppb | 0.06 | — | — | — | — | — | 156× over |
| Trichloroacetic acid Disinfection byproduct |
5.76 ppb | 0.1 | — | — | — | — | — | 58× over |
| Chloroform Disinfection byproduct |
21.9 ppb | 0.4 | — | — | — | — | — | 55× over |
| Dichloroacetic acid Disinfection byproduct |
9.61 ppb | 0.2 | — | — | — | — | — | 48× over |
| Dibromochloromethane Disinfection byproduct |
4.03 ppb | 0.1 | — | — | — | — | — | 40× over |
| Dibromoacetic acid Disinfection byproduct |
0.607 ppb | 0.03 | — | — | — | — | — | 20× over |
| Chromium (hexavalent) Heavy metal |
0.13 ppb | 0.02 | — | — | — | — | — | 6.5× over |
| Perfluorooctanoic acid (PFOA) PFAS |
0.48 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | 5.3× over |
| Nitrate Inorganic |
0.33 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 2.4× over |
| Tritium Other |
702.67 pCi/L | 400.0 | — | — | — | — | — | 1.8× over |
| Perfluorooctane sulfonate (PFOS) PFAS |
0.4 ppt | 0.3 | 4.0 | 100 | 100 | 1 | — | 1.3× over |
| Chlorate Disinfection byproduct |
64.0 ppb | 210.0 | — | — | — | — | — | Below guideline |
| Bromoform Disinfection byproduct |
0.102 ppb | 0.5 | — | — | — | — | — | Below guideline |
| 1,4-Dioxane Semi-volatile organic compound |
0.0403 ppb | 0.35 | — | — | 50 | 1 | — | Below guideline |
| Manganese Heavy metal |
1.95 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Vanadium Other |
0.404 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
4.26 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
3.78 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.0219 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.0393 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.62 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 ROCK HILL CITY OF (SC4610002).