What was found in Hockessin's water
The highest level seen across the city's suppliers, the EPA limit for each, and where the figure comes from.
| Contaminant | Level vs EPA limit | Suppliers | Source |
|---|---|---|---|
| Nitrate | 8110 µg/L 81% of the EPA limit 10000 µg/L | 1/1 | SYR4 |
| Nitrate-Nitrite | 7940 µg/L 79% of the EPA limit 10000 µg/L | 1/1 | SYR4 |
| Fluoride | 1800 µg/L 45% of the EPA limit 4000 µg/L | 1/1 | SYR4 |
| Copper | 442 µg/L 34% of the EPA limit 1300 µg/L | 1/1 | SYR4 |
| Barium | 233 µg/L 12% of the EPA limit 2000 µg/L | 1/1 | SYR4 |
| TTHM | 119 µg/L 149% of the EPA limit, in the worst sample — 80 µg/L | 1/1 | SYR4 |
| Chloroform | 111 µg/L No EPA limit set | 1/1 | SYR4 |
| Total Haloacetic Acids (HAA5) | 99.4 µg/L 166% of the EPA limit, in the worst sample — 60 µg/L | 1/1 | SYR4 |
| Lead | 82.9 µg/L 553% of the EPA limit, in the worst sample — 15 µg/L | 1/1 | SYR4 |
| Dichloroacetic Acid | 58 µg/L No EPA limit set | 1/1 | SYR4 |
| Trichloroacetic Acid | 41.4 µg/L No EPA limit set | 1/1 | SYR4 |
| Bromodichloromethane | 21 µg/L No EPA limit set | 1/1 | SYR4 |
| Chromium | 19 µg/L 19% of the EPA limit 100 µg/L | 1/1 | SYR4 |
| Tetrachloroethylene | 16.6 µg/L 332% of the EPA limit, in the worst sample — 5 µg/L | 1/1 | SYR4 |
| Combined Radium (-226 And -228) | 15.2 pCi/L 304% of the EPA limit, in the worst sample — 5 pCi/L | 1/1 | SYR4 |
| Xylenes, Total | 15.1 µg/L 0.2% of the EPA limit 10000 µg/L | 1/1 | SYR4 |
| Monochloroacetic Acid | 9.9 µg/L No EPA limit set | 1/1 | SYR4 |
| Selenium | 9.4 µg/L 19% of the EPA limit 50 µg/L | 1/1 | SYR4 |
| Toluene | 6.9 µg/L 0.7% of the EPA limit 1000 µg/L | 1/1 | SYR4 |
| Dibromochloromethane | 4.1 µg/L No EPA limit set | 1/1 | SYR4 |
| Di(2-ethylhexyl) Phthalate | 3.5 µg/L 58% of the EPA limit 6 µg/L | 1/1 | SYR4 |
| Chlorobenzene | 2.8 µg/L 2.8% of the EPA limit 100 µg/L | 1/1 | SYR4 |
| Bromoform | 2.5 µg/L No EPA limit set | 1/1 | SYR4 |
| Toxaphene | 2.5 µg/L 83% of the EPA limit 3 µg/L | 1/1 | SYR4 |
| Ethylbenzene | 2.1 µg/L 0.3% of the EPA limit 700 µg/L | 1/1 | SYR4 |
| Dibromoacetic Acid | 1.97 µg/L No EPA limit set | 1/1 | SYR4 |
| cis-1,2-Dichloroethylene | 1.7 µg/L 2.4% of the EPA limit 70 µg/L | 1/1 | SYR4 |
| 1,2-Dichloroethane | 1.5 µg/L 30% of the EPA limit 5 µg/L | 1/1 | SYR4 |
| Arsenic | 1.4 µg/L 14% of the EPA limit 10 µg/L | 1/1 | SYR4 |
| Chlordane | 1.01 µg/L 51% of the EPA limit 2 µg/L | 1/1 | SYR4 |
| Trichloroethylene | 0.9300 µg/L 19% of the EPA limit 5 µg/L | 1/1 | SYR4 |
| Mercury | 0.8000 µg/L 40% of the EPA limit 2 µg/L | 1/1 | SYR4 |
| Pentachlorophenol | 0.4700 µg/L 47% of the EPA limit 1 µg/L | 1/1 | SYR4 |
| Atrazine | 0.3900 µg/L 13% of the EPA limit 3 µg/L | 1/1 | SYR4 |
| Benzene | 0.3400 µg/L 6.8% of the EPA limit 5 µg/L | 1/1 | SYR4 |
| 1,1-Dichloroethylene | 0.3200 µg/L 4.6% of the EPA limit 7 µg/L | 1/1 | SYR4 |
| Di(2-ethylhexyl) Adipate | 0.1600 µg/L 0% of the EPA limit 400 µg/L | 1/1 | SYR4 |
| 1,1,1-Trichloroethane | 0.1400 µg/L 0.1% of the EPA limit 200 µg/L | 1/1 | SYR4 |
| Thallium, Total | 0.1200 µg/L 6% of the EPA limit 2 µg/L | 1/1 | SYR4 |
| Pfpea | 0.1060 µg/L No EPA limit set | 1/1 | UCMR-5 |
| Pfba | 0.0791 µg/L No EPA limit set | 1/1 | UCMR-5 |
| Pfhxa | 0.0722 µg/L No EPA limit set | 1/1 | UCMR-5 |
| Cadmium | 0.0400 µg/L 0.8% of the EPA limit 5 µg/L | 1/1 | SYR4 |
| Heptachlor Epoxide | 0.0373 µg/L 19% of the EPA limit 0.2000 µg/L | 1/1 | SYR4 |
| PFOA | 0.0231 µg/L No EPA limit set | 1/1 | UCMR-5 |
| Pfhpa | 0.0189 µg/L No EPA limit set | 1/1 | UCMR-5 |
| PFHXS | 0.0089 µg/L No EPA limit set | 1/1 | UCMR-5 |
| PFBS | 0.0087 µg/L No EPA limit set | 1/1 | UCMR-5 |
| PFOS | 0.0060 µg/L No EPA limit set | 1/1 | UCMR-5 |
| Lead | 0.0010 mg/L 6.7% of the EPA limit 0.0150 mg/L | 1/1 | LCR |
Each bar shows the measured level as a share of the EPA limit: green is
well under, amber is close to it, red is over. For lead and copper the
limit applies to exactly the 90th-percentile figure shown, so red there
means a real exceedance. For everything else the limit applies to a
running annual average while the figure is the single worst sample on
record — over 100% is worth reading, but is not by itself a violation.
Formal violations are listed separately.
These are the utilities' own EPA-reported results, not a city-wide
average. A detection means the lab measured the
substance — it isn't the same as exceeding a legal limit. Hover a source
tag to see the EPA program and years behind each figure.
Water suppliers serving Hockessin
| Supplier | Population served |
|---|---|
| ARTESIAN WATER COMPANY | 231,114 |
Frequently asked questions about Hockessin tap water
Is Hockessin tap water safe to drink?
EPA testing detected 50 contaminants in the water serving Hockessin. A detection isn't the same as a violation — most detected levels are within federal limits. Check the level and source for each contaminant above, and your utility's annual Consumer Confidence Report for the official compliance status.
How many water suppliers serve Hockessin?
1 public water supplier report drinking-water monitoring for Hockessin, Delaware to the EPA. Each is listed above with its population served.
What contaminants are in Hockessin's water?
The contaminants EPA monitoring detected in Hockessin include Nitrate, Nitrate-Nitrite, Fluoride, Copper, Barium. The full list, with the highest level found and the data source, is in the table above.
Where does this data come from?
Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.