Drinking water quality · 2023
· Verified
· PWSID FL4130871
What's in Miami Dade, FL tap water
4 contaminants in Miami Dade, FL's water sat at or above a federal limit, led by PFOS (Perfluorooctane sulfonic acid) at 8.3x the limit.
- !4 contaminants at or above a federal limit — worst is PFOS (Perfluorooctane sulfonic acid) at 8.3x
- !2 contaminants within 20% of a limit
- !17 of 27 core regulated contaminants reported — 10 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
- −8 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
- −3 core regulated contaminants never reported (17/27)
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
- PFOS (Perfluorooctane sulfonic acid)8.3× the federal limit33 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 U.S. systems
- PFOA (Perfluorooctanoic acid)3.5× the federal limit14 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 95% of U.S. systems
- HAA51.4× the federal limit3–81 ug/L · limit 60 ug/L
Long-term exposure above the federal limit is associated with an increased cancer risk.
higher than 95% of U.S. systems
- Chloramine1.1× the federal limit0.6–4.2 mg/L · limit 4 mg/L
Holds disinfection further into the pipe network, but is regulated under the same residual-disinfectant cap as chlorine.
higher than 90% of U.S. systems
- PFHxS (Perfluorohexane sulfonic acid)94% of the federal limit9.4 ng/L · limit 10 ng/L
Regulated by the EPA at 10 parts per trillion and included in the PFAS Hazard Index.
higher than 80% of U.S. systems
- TTHM89% of the federal limit11–71 ug/L · limit 80 ug/L
Long-term exposure above the federal limit is linked to liver, kidney, and central-nervous-system effects and increased cancer risk.
higher than 90% of U.S. systems
+28 contaminants were measured and came in below the limitShow all
| Contaminant | Measured | Federal limit |
|---|---|---|
| Nitrate | 2–7 mg/L | 10 mg/L |
| Chlorine | 0.4–2.6 mg/L | 4 mg/L |
| PFNA (Perfluorononanoic acid) | 6.5 ng/L | 10 ng/L |
| Gross Alpha | 0–5 pCi/L | 15 pCi/L |
| Uranium | 0.7–9 ug/L | 30 ug/L |
| Fluoride | 0.5–1 mg/L | 4 mg/L |
| Lead | 0.0031 mg/L | 0.015 mg/L |
| Nitrite | 0–0.2 mg/L | 1 mg/L |
| Arsenic | 0.6–2 ug/L | 10 ug/L |
| Combined Radium | 0–1 pCi/L | 5 pCi/L |
| Antimony | 0.07–0.5 ug/L | 6 ug/L |
| Pentachlorophenol | 0–0.038 ug/L | 1 ug/L |
| Chromium | 0–2 ug/L | 100 ug/L |
| Selenium | 0–0.8 ug/L | 50 ug/L |
| Barium | 0.01–0.02 mg/L | 2 mg/L |
| Thallium | 0.01–0.02 ug/L | 2 ug/L |
| Copper | 1.1 % | 1.3 % |
| Sodium | 23–33 mg/L | — |
| Total Coliform | 0 | — |
| PFAS | 0.2–1.3 | — |
| Radon | 0–197 pCi/L | — |
| PFBA | 22 ng/L | — |
| 6:2 FTS | 0.19 µg/L | — |
| PFHpA | 20 ng/L | — |
| PFPeA | 56 ng/L | — |
| PFBS | 4.6 ng/L | — |
| PFHxA | 58 ng/L | — |
| 8:2 FTS | 0.0096 µg/L | — |
What this report doesn't tell you
10 of the 27 contaminants a community water system normally reports do not appear anywhere in Miami Dade, FL's data. Absent is not the same as absent-from-the-water — it means nobody published a number.
+Full detail: PFAS testing, water source, historical monitoring, and the federal violation record
PFAS — EPA UCMR5 (2023–2025)
2 PFAS compounds above EPA limits in Miami Dade, FL
The EPA finalized the first-ever federal drinking-water limits for six PFAS compounds in April 2024. These numbers come straight from EPA's UCMR5 lab dataset — every U.S. system serving more than 3,300 people tested every PFAS sample at an entry point to its distribution system. PFAS not listed below were either tested and not detected, or not yet sampled.
PFOS (Perfluorooctane sulfonic acid)
● Over EPA limit (8.3×)PFOA (Perfluorooctanoic acid)
● Over EPA limit (3.5×)PFHxS (Perfluorohexane sulfonic acid)
● Approaching limit (94%)PFNA (Perfluorononanoic acid)
● Below limitPFBA
● Detected (no federal limit)6:2 FTS
● Detected (no federal limit)PFHpA
● Detected (no federal limit)PFPeA
● Detected (no federal limit)PFBS
● Detected (no federal limit)PFHxA
● Detected (no federal limit)8:2 FTS
● Detected (no federal limit)Where your water comes from · EPA SDWIS
Miami Dade, FL's drinking water comes from ground water, drawn from 77 sources.
Source
- WELL · 23
- ORR WELLFIELD · 22
- HIALEAH-MIAMI SPRINGS · 19
- PRESTON PLANT · 4
- + 5 more
Treatment
- MDWASD/ALEXANDER ORR
- MDWASA/HIALEAH
- MDWASA/JOHN PRESTON
Distribution
Compliance history
Federal Safe Drinking Water Act violation & enforcement records (EPA SDWIS). A violation is a regulatory determination by the state or EPA — separate from the measured levels above.