Saving Biscayne Bay: Miami-Dade’s septic tanks have to go, scientist says

MIAMI – Scientists know there is evidence that polluted groundwater flows from coastal septic systems to the sea. Environmentalists worry that local leaders’ refusal to invest in a much-needed septic-to-sewer conversion could end up costing more if Miami-Dade County’s coastal water quality continues to fail.

Septic systems process wastewater from toilets, sinks, and showers. The Environmental Protection Agency’s list of septic tanks’ benefits includes “recharges” to groundwater. But this is precisely why Jim Fourqurean and other experts believe septic systems shouldn’t be in coastal areas like Palmetto Bay.

Fourqurean, the director of the Center for Coastal Oceans Research at Florida International University, is among the experts who blame septic systems for the nitrogen-enriched groundwater that is causing algae blooms and oxygen depletion problems.

“The seagrass that is really close to shore is being impacted by that groundwater,” Fourqurean said.

Scientists in South Florida say there have been many warnings of the water quality crisis. The most recent alarming episode: The unprecedented fish kill starting Aug. 10 in the northern area of Biscayne Bay. Videos of dead fish and struggling marine life went viral in Miami-Dade County.

“We should stop polluting the groundwater because in Florida that groundwater that our septic tanks discharge into just bubbles up right in the bay,” Fourqurean said. “We have to stop.”

Last week’s algae bloom prompted fears that the fish kill wasn’t over, but the winds and currents pushed it out of the bay. Dozens of demonstrators marched in protest on Saturday in North Bay Village. The crowd included waterfront residents, swimmers, paddle boarders, and others who regularly enjoy the beauty of the bay and have seen a decline.

On Monday, the Biscayne Bay Task Force submitted a report to the Miami-Dade County Commission with more than 60 recommendations — including what they say is a need to switch 100,000 homes from septic tanks to sewer lines. Miami-Dade Mayor Carlos Gimenez disputed the need and said it is a costly proposition: $7,500 per home.

Experts have already warned Miami-Dade County about the vulnerabilities of the septic tank system. A November 2018 66-page report focused solely on the vulnerability to sea-level rise.

For more information about the ongoing Biscayne Bay crisis, watch the Local 10 News’ “Saving Biscayne Bay” special at 8 p.m. on Wednesday and join the subsequent virtual town hall with Florida International University on or Local 10 News on Facebook.

About the Authors:

Louis Aguirre is an Emmy-award winning journalist who anchors weekday newscasts and serves as WPLG Local 10’s Environmental Advocate.

The Emmy Award-winning journalist joined the Local 10 News team in 2013. She wrote for the Miami Herald for more than 9 years and won a Green Eyeshade Award.