Is Miami, FL Tap Water Safe to Drink?

Where Does Miami Get Its Water?

Miami's drinking water is supplied primarily by Miami-Dade Water and Sewer, one of the largest water utilities in Florida, along with the City of Hialeah's water system. Together these utilities serve the vast majority of Miami-area residents.

The water is treated at several major plants. The Alexander Orr Water Treatment Plant and the Preston Water Treatment Plant are two of Miami-Dade's principal facilities. Hialeah operates its own treatment works, including a reverse osmosis plant. These facilities collectively handle the bulk of the treated water delivered to Miami taps.

A small portion of the service area overlaps with Palm Beach County Water Utilities coverage, though Miami-Dade Water and Sewer and the City of Hialeah serve the core city population.

How Is Miami Tap Water Treated?

Miami's treatment plants use a multi-step process that includes coagulation, filtration, and in some facilities reverse osmosis to remove dissolved minerals and contaminants. Granular activated carbon and ion exchange are also part of the treatment toolkit at various plants, helping to reduce organic compounds and other impurities before water reaches your tap.

For disinfection, the utilities use a combination of approaches including free chlorine, ozone, and other chemical disinfectants depending on the facility. Disinfection kills bacteria and viruses and is required by federal rules. A residual disinfectant travels with the water through pipes to your home, which can sometimes affect taste or odor.

Membrane filtration is used at certain facilities, particularly those with reverse osmosis capability, adding another barrier against contaminants. This layered approach reflects the complexity of treating water in South Florida, where source water quality can vary.

What's in Miami Tap Water?

The standout finding in recent EPA testing is 6:2 FTS, a type of PFAS (per- and polyfluoroalkyl substance). The highest detected level was 0.129 µg/L, which is more than 25 times above EPA's health reference level of 0.005 µg/L. Detections were recorded across 25 of the city's ZIP codes, making this a citywide concern rather than an isolated one.

Several other PFAS compounds were also detected. PFPeA reached a peak of 0.037 µg/L and PFHxA reached 0.035 µg/L; both were found across all 26 monitored ZIP codes, though neither exceeded their respective screening benchmarks. PFOS, another well-known PFAS, was detected at up to 0.028 µg/L across 26 ZIP codes and also remained below its screening level.

Lithium was detected at up to 59 µg/L in one ZIP code, which is well above EPA's health reference level of 10 µg/L. It is important to note that there is currently no federally enforceable drinking water standard (maximum contaminant level) for lithium; the 10 µg/L figure is a non-regulatory screening benchmark, not a legal limit. PFAS compounds like 6:2 FTS can enter water supplies from industrial sources, firefighting foam, and consumer product residues that persist in the environment.

Health Risk Profile for Miami

The primary concern in Miami's tap water is 6:2 FTS, a PFAS compound detected at up to 0.129 µg/L against EPA's health reference level of 0.005 µg/L. This reference level is a non-enforceable screening benchmark, but EPA uses it to flag concentrations where long-term exposure may carry health risks. Research on 6:2 FTS is still developing, and it is part of a broader class of chemicals linked to immune, hormonal, and developmental effects at sustained exposures.

Infants, young children, pregnant individuals, and people who are immunocompromised are generally considered more sensitive to PFAS exposure. For these groups, reducing daily exposure through a point-of-use filter is a reasonable precaution given the detected levels.

For Miami households, a filter certified to NSF/ANSI 58 (reverse osmosis) or NSF/ANSI P473 is the most effective option for reducing PFAS in tap water. NSF/ANSI is an independent third-party certification program, so look for those specific labels on the filter packaging when shopping. These certifications mean the product has been independently tested and verified to reduce PFAS to low levels.

For lithium, because no enforceable federal maximum contaminant level exists, there is no regulatory violation involved. The single ZIP code with a reading of 59 µg/L is above the screening benchmark, and individuals with specific health concerns about lithium may wish to consult a physician, but the broader scientific picture on lithium in drinking water is still being studied.