How to Read Your Miami-Dade Water Quality Report
Every water utility must publish a yearly Water Quality Report, also called a Consumer Confidence Report, by July 1. It lists what was detected in the water and compares each result to the EPA's limits. The key is reading three columns side by side: what was found, the legal limit (MCL), and the health goal (MCLG).
Where to Find the Report
The Miami-Dade Water and Sewer Department posts its report on the county website each year. If your city buys water from the county or runs its own utility, such as Hialeah or North Miami Beach, check your city's report too.
The Terms That Matter
MCL (Maximum Contaminant Level): the highest level legally allowed. It's enforceable.
MCLG (MCL Goal): the level with no known health risk. It isn't enforceable, and for some contaminants it's zero.
MRDL / MRDLG: the same idea, for disinfectants like chloramine.
AL (Action Level): for lead and copper. If too many homes test above it, the utility must take action.
90th percentile: for lead and copper, 90% of homes tested at or below this number.
ppm / ppb / ppt: parts per million, billion and trillion. 1 ppb is like one drop in a backyard pool.
ND: not detected at the lab's testing limit.
How to Read a Row
Each row lists a contaminant, the amount detected (often an average and a range), the MCL, the MCLG, whether there was a violation, and the likely source. Look for two things:
1. The gap between the detected level and the MCLG. A result can be legal, below the MCL, and still above the health goal.
2. The range, not just the average. A low average can hide higher readings at some locations or times.
What Miami Residents Usually See
Disinfectant (chloramine): listed with its MRDL of 4 ppm.
Disinfection byproducts (TTHMs and HAA5): form when chloramine reacts with natural organic matter.
Lead and copper: reported as a 90th percentile from home taps, not the plant.
Hardness, sodium and minerals: often shown in a separate table of "secondary" or unregulated results.
Unregulated monitoring (UCMR): testing for contaminants without federal limits yet, including PFAS.
What the Report Doesn't Tell You
The report reflects water samples from the county system, not your faucet. Your home's plumbing, its age and how long water sits in the pipes all affect what comes out of your tap. Starting in 2027, utilities serving 10,000 or more people must send reports twice a year and include a plain-language summary.
Which System Handles This
Chloramine and hardness: the Hydronex iGen C, for every tap.
Lead, PFAS and other health-related contaminants: the Micromax 8500 reverse osmosis system, for drinking water.