Water Quality Report · Updated May 12, 2026
CHESTER WATER AUTHORITY
CHESTER WATER AUTHORITY delivers tap water graded D (59/100) by TapWaterSafety.org. The utility serves approximately 140,437 residents in CHESTER, Pennsylvania 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; Total trihalomethanes (TTHMs) significantly above health guideline. For questions, the utility can be reached at 610-876-8185.
Is CHESTER tap water safe to drink?
CHESTER WATER AUTHORITY delivers tap water that earns a grade of D (59/100) from TapWaterSafety.org — a below-average rating, with multiple concerns including pfas contamination.
The utility serves 140,437 residents in CHESTER, drawing from surface water.
Public testing data identifies 11 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA9), Haloacetic acids (HAA5), Total trihalomethanes (TTHMs), Trichloroacetic acid, Bromodichloromethane, Dichloroacetic acid, Chloroform, Perfluorooctanoic acid (PFOA), Nitrate, Chromium (hexavalent), Dibromochloromethane. 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.
Quick actions for CHESTER residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for CHESTER WATER AUTHORITY.
PFAS contamination
Severe concernPerfluorooctanoic 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 46.3 ppb, 772x above the EWG health guideline of 0.06 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 34.9 ppb, 349x above the EWG health guideline of 0.1 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 39.4 ppb, 263x above the EWG health guideline of 0.15 ppb.
Contact CHESTER WATER AUTHORITY
Reach the utility directly for service issues, water quality concerns, or to request your Consumer Confidence Report.
General Contact
Treatment Plant
Recommended water filters for CHESTER
Filters matched to the specific contaminants in this water supply.
Reverse Osmosis or NSF P473 certified carbon
$80-$750Activated carbon and RO are the only technologies proven to remove PFAS at certified levels.
Carbon block (NSF/ANSI 42 + 53)
$40-$750Activated carbon is highly effective for disinfection byproducts like TTHM and HAA5.
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 59/100 breaks down across five weighted components. Read the full methodology →
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 |
46.3 ppb | 0.06 | — | — | — | — | — | 772× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
34.9 ppb | 0.1 | 60.0 | 60 | — | — | — | 349× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
39.4 ppb | 0.15 | 80.0 | 100 | — | — | — | 263× over |
| Trichloroacetic acid Disinfection byproduct |
15.7 ppb | 0.1 | — | — | — | — | — | 157× over |
| Bromodichloromethane Disinfection byproduct |
6.85 ppb | 0.06 | — | — | — | — | — | 114× over |
| Dichloroacetic acid Disinfection byproduct |
18.9 ppb | 0.2 | — | — | — | — | — | 94× over |
| Chloroform Disinfection byproduct |
32.3 ppb | 0.4 | — | — | — | — | — | 81× over |
| Perfluorooctanoic acid (PFOA) PFAS |
3.23 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | 36× over |
| Nitrate Inorganic |
4.3 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 31× over |
| Chromium (hexavalent) Heavy metal |
0.0963 ppb | 0.02 | — | — | — | — | — | 4.8× over |
| Dibromochloromethane Disinfection byproduct |
0.344 ppb | 0.1 | — | — | — | — | — | 3.4× over |
| Dibromoacetic acid Disinfection byproduct |
0.0236 ppb | 0.03 | — | — | — | — | — | Below guideline |
| Atrazine Pesticide/Herbicide |
0.0525 ppb | 0.1 | 3.0 | 0.1 | 100 | 0.15 | — | Below guideline |
| Barium Heavy metal |
29.0 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Manganese Heavy metal |
2.18 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Vanadium Other |
0.138 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
0.225 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
3.83 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
3.67 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.0413 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
2.97 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.118 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.556 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Testosterone Other |
0.05 ppt | — | — | — | — | — | — | 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.
CHESTER WATER AUTHORITY service area
This water system serves 1 community in Delaware County, Pennsylvania. Click any city for its dedicated tap water quality page.
Find the right filter for CHESTER water
Browse filter categories by water-quality concern. Each option below is NSF-certified for the matched contaminant type.