Water Quality Report · Updated May 12, 2026
DEL-CO WATER COMPANY, INC.
DEL-CO WATER COMPANY, INC. delivers tap water graded D (57/100) by TapWaterSafety.org. The utility serves approximately 150,000 residents in DELAWARE, Ohio using surface water. 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. For questions, the utility can be reached at 740-201-0125.
Is DELAWARE tap water safe to drink?
DEL-CO WATER COMPANY, INC. delivers tap water that earns a grade of D (57/100) from TapWaterSafety.org — a below-average rating, with multiple concerns including pfas contamination.
The utility serves 150,000 residents in DELAWARE, drawing from surface water. Despite being legal under US EPA standards, this water would fail the European Union's Drinking Water Directive, primarily due to pfas contamination.
Public testing data identifies 15 contaminants in this water above EWG's health-based guidelines, including: Haloacetic acids (HAA9), Total trihalomethanes (TTHMs), Haloacetic acids (HAA5), Bromodichloromethane, Trichloroacetic acid, Chloroform, Dichloroacetic acid, Dibromochloromethane, Chromium (hexavalent), Dibromoacetic acid, Nitrate and nitrite, Nitrate, Atrazine, Chlorate, Perfluorooctanoic acid (PFOA). 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 DELAWARE residents
Top concerns in this water
Based on the most recent EPA and EWG data, these are the most significant water quality issues for DEL-CO WATER COMPANY, INC..
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 46.5 ppb, 774x above the EWG health guideline of 0.06 ppb.
Total trihalomethanes (TTHMs) significantly above health guideline
Moderate concernTotal trihalomethanes (TTHMs) detected at 55.9 ppb, 373x above the EWG health guideline of 0.15 ppb.
Haloacetic acids (HAA5) significantly above health guideline
Moderate concernHaloacetic acids (HAA5) detected at 36.6 ppb, 366x above the EWG health guideline of 0.1 ppb.
Contact DEL-CO WATER COMPANY, INC.
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 DELAWARE
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 57/100 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 |
46.5 ppb | 0.06 | — | — | — | — | — | 774× over |
| Total trihalomethanes (TTHMs) Disinfection byproduct |
55.9 ppb | 0.15 | 80.0 | 100 | — | — | — | 373× over |
| Haloacetic acids (HAA5) Disinfection byproduct |
36.6 ppb | 0.1 | 60.0 | 60 | — | — | — | 366× over |
| Bromodichloromethane Disinfection byproduct |
13.1 ppb | 0.06 | — | — | — | — | — | 218× over |
| Trichloroacetic acid Disinfection byproduct |
17.0 ppb | 0.1 | — | — | — | — | — | 170× over |
| Chloroform Disinfection byproduct |
39.3 ppb | 0.4 | — | — | — | — | — | 98× over |
| Dichloroacetic acid Disinfection byproduct |
15.8 ppb | 0.2 | — | — | — | — | — | 79× over |
| Dibromochloromethane Disinfection byproduct |
3.53 ppb | 0.1 | — | — | — | — | — | 35× over |
| Chromium (hexavalent) Heavy metal |
0.296 ppb | 0.02 | — | — | — | — | — | 15× over |
| Dibromoacetic acid Disinfection byproduct |
0.296 ppb | 0.03 | — | — | — | — | — | 9.9× over |
| Nitrate and nitrite Inorganic |
0.849 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 6.1× over |
| Nitrate Inorganic |
0.845 ppm | 0.14 | 10.0 | 11.3 | 11.3 | 10 | — | 6.0× over |
| Atrazine Pesticide/Herbicide |
0.342 ppb | 0.1 | 3.0 | 0.1 | 100 | 0.15 | — | Fails EU |
| Chlorate Disinfection byproduct |
431.4 ppb | 210.0 | — | — | — | — | — | 2.1× over |
| Perfluorooctanoic acid (PFOA) PFAS |
0.191 ppt | 0.09 | 4.0 | 100 | 100 | 0.007 | — | 2.1× over |
| Molybdenum Other |
10.6 ppb | 40.0 | — | — | — | — | — | Below guideline |
| Simazine Pesticide/Herbicide |
0.00854 ppb | 0.1 | 4.0 | — | — | — | — | Below guideline |
| Monochloroacetic acid Disinfection byproduct |
3.42 ppb | 53.0 | — | — | — | — | — | Below guideline |
| Bromoform Disinfection byproduct |
0.0156 ppb | 0.5 | — | — | — | — | — | Below guideline |
| Barium Heavy metal |
9.22 ppb | 700.0 | 2000.0 | — | 1300 | 2000 | — | Below guideline |
| Perfluorobutanoic Acid (PFBA) PFAS |
3.68 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Manganese Heavy metal |
0.309 ppb | 100.0 | — | 50 | 80 | — | — | Below guideline |
| Monobromoacetic acid Disinfection byproduct |
0.074 ppb | 25.0 | — | — | — | — | — | Below guideline |
| Perfluorohexanoic Acid (PFHxA) PFAS |
2.85 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Vanadium Other |
0.0569 ppb | 21.0 | — | — | — | — | — | Below guideline |
| Perfluoropentanoic Acid (PFPeA) PFAS |
2.29 ppt | 1000.0 | — | — | — | — | — | Below guideline |
| Strontium Radiological |
0.566 ppb | 1500.0 | — | — | — | — | — | Below guideline |
| Perfluorobutane sulfonate (PFBS) PFAS |
0.668 ppt | 2000.0 | — | — | — | — | — | Below guideline |
| Fluoride Inorganic |
0.961 ppm | — | 4.0 | 1.5 | 1.5 | — | — | Below guideline |
| Lithium Other |
2.52 ppb | — | — | — | — | — | — | Below guideline |
| Nitrite Inorganic |
0.00571 ppm | — | 1.0 | — | — | — | — | 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.
DEL-CO WATER COMPANY, INC. service area
This water system serves 1 community in Delaware County, Ohio. Click any city for its dedicated tap water quality page.
Find the right filter for DELAWARE water
Browse filter categories by water-quality concern. Each option below is NSF-certified for the matched contaminant type.