Drinking water quality · 2024
· Verified
What's in Downey, CA tap water
2 contaminants in Downey, CA's water sat at or above a federal limit, led by PFOS at 7.4x the limit.
- !2 contaminants at or above a federal limit — worst is PFOS at 7.4x
- !12 of 27 core regulated contaminants reported — 15 never appear in this report
- ✓No open federal violations
+How this score is calculated
Every system starts at 100. Points come off for measured levels, for the federal violation record, and for how much of the core regulated set the utility actually reported. All three inputs are the utility's own published numbers and EPA's own records.
- −60 contaminants at or above a federal limit
- −0 contaminants within 20% of a limit
- −0 open health-based violations
- −0 open monitoring / reporting violations
- −0 health-based violations resolved in the last 5 years
- −11 core regulated contaminants never reported (12/27)
A 90–100 · B 80–89 · C 70–79 · D 60–69 · F below 60. A system reporting under a third of the core set is capped at C however clean its numbers look — a short report is not a clean bill of health.
Full grading methodology, constant for constant →What to worry about
- PFOS7.4× the federal limit29.5 ng/L · limit 4 ng/L
Linked to cancer, thyroid disease, and immune effects; the EPA set an enforceable limit of 4 parts per trillion.
Higher than 95% of CA systems that report it · higher than 95% of U.S. systems
- PFOA3.1× the federal limit12.3 ng/L · limit 4 ng/L
Linked to cancer, liver damage, and immune effects; the EPA set an enforceable limit of 4 parts per trillion.
Higher than 90% of CA systems that report it · higher than 90% of U.S. systems
+34 contaminants were measured and came in below the limitShow all
| Contaminant | Measured | Federal limit |
|---|---|---|
| Perfluorohexanesulfonic acid | 4.8 ng/L | 10 ng/L |
| Nitrate | 3.46 mg/L | 10 mg/L |
| Turbidity | 0.3 NTU | 1 NTU |
| Lead | 2.8 ug/L | 15 ug/L |
| Copper | 0.23 mg/L | 1.3 mg/L |
| Fluoride | 0.31 mg/L | 4 mg/L |
| Chloride | 91 mg/L | — |
| Sulfate | 112 mg/L | — |
| Aluminum | Not detected ug/L | — |
| Arsenic | Not detected ug/L | 10 ug/L |
| Calcium | 80 mg/L | — |
| Iron | Not detected ug/L | — |
| Magnesium | 15.9 mg/L | — |
| Manganese | 0.19 ug/L | — |
| Potassium | 4.5 mg/L | — |
| Sodium | 60.1 mg/L | — |
| Total Coliform | 1.9 % | — |
| Chromium | 0.67 pCi/L | — |
| Perfluorobutanesulfonic acid | 6.8 ng/L | — |
| Perfluoroheptanoic acid | 1 ng/L | — |
| Perfluorohexanoic acid | 10 ng/L | — |
| Perfluoropentanoic acid | 11.5 ng/L | — |
| PFBA | 5.7 ng/L | — |
| Alkalinity | 168 mg/L | — |
| Bicarbonate | 206 mg/L | — |
| Hardness | 15.7 | — |
| Odor | Not detected | — |
| pH | 7.5 | — |
| Specific Conductance | 818 | — |
| Total Dissolved Solids | 491 mg/L | — |
| Gross Alpha | Not detected pCi/L | 15 pCi/L |
| Uranium | 1.06 pCi/L | 20 pCi/L |
| Tetrachloroethylene | Not detected ug/L | 5 ug/L |
| Trichloroethylene | Not detected ug/L | 5 ug/L |
What this report doesn't tell you
15 of the 27 contaminants a community water system normally reports do not appear anywhere in Downey, CA's data. Absent is not the same as absent-from-the-water — it means nobody published a number.