Drinking water quality · 2024
· Verified
What's in Tempe, AZ tap water
2 contaminants in Tempe, AZ's water sat at or above a federal limit, led by PFOS at 2.3x the limit.
- !2 contaminants at or above a federal limit — worst is PFOS at 2.3x
- !16 of 27 core regulated contaminants reported — 11 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.
- −42 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
- −5 core regulated contaminants never reported (16/27)
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
- PFOS2.3× the federal limit9 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 75% of U.S. systems
- PFOA1.3× the federal limit5 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 70% of U.S. systems
+27 contaminants were measured and came in below the limitShow all
| Contaminant | Measured | Federal limit |
|---|---|---|
| Nitrate | 0–7 mg/L | 10 mg/L |
| Perfluorohexanesulfonic acid | 7 ng/L | 10 ng/L |
| TTHM | 52 ug/L | 80 ug/L |
| Arsenic | 0–5 ug/L | 10 ug/L |
| Lead | 4.5 ug/L | 15 ug/L |
| Chlorine | 0.02–1.1 mg/L | 4 mg/L |
| HAA5 | 15 ug/L | 60 ug/L |
| Fluoride | 0–0.97 mg/L | 4 mg/L |
| Uranium | 0–7 ug/L | 30 ug/L |
| Turbidity | 0.19 NTU | 1 NTU |
| Tetrachloroethylene | 0–0.7 ug/L | 5 ug/L |
| Trichloroethylene | 0–0.7 ug/L | 5 ug/L |
| Gross Alpha | 0–2 pCi/L | 15 pCi/L |
| Copper | 0.14 mg/L | 1.3 mg/L |
| Chromium | 0–10 ug/L | 100 ug/L |
| Barium | 0.04–0.09 mg/L | 2 mg/L |
| Selenium | 0–1 ug/L | 50 ug/L |
| Hexafluoropropylene oxide dimer acid | 0.01 ng/L | 10 ng/L |
| Lithium | 141 ug/L | — |
| Perfluorobutanesulfonic acid | 11 ng/L | — |
| Perfluoroheptanoic acid | 1 ng/L | — |
| Perfluorohexanoic acid | 3 ng/L | — |
| Perfluorononanoic acid | Not detected ng/L | 10 ng/L |
| Perfluoropentanesulfonic acid (PFPeS) | 1 ng/L | — |
| Perfluoropentanoic acid | 2 ng/L | — |
| PFBA | 1 ng/L | — |
| TOC | 1.3–3.6 mg/L | — |
What this report doesn't tell you
11 of the 27 contaminants a community water system normally reports do not appear anywhere in Tempe, AZ's data. Absent is not the same as absent-from-the-water — it means nobody published a number.