Five million gallons of wastewater spilled into Biscayne Bay and surrounding bodies of water in Northeast Miami-Dade following torrential rain last weekend, prompting the county to issue an advisory warning people to refrain from swimming, fishing or engaging in other recreational activities until further testing of the contaminated waters is completed.
The advisory is still in effect.
According to the county, the tainted waters where the advisory is being enforced include the Oleta River, the beach area in Oleta River State Park from the eastern shore of Biscayne Bay to Biscayne Boulevard, Haulover Inlet, and the area between the inlet and the south end of Dumbfoundling Bay, including Maul Lake and Sand Spur Island and surrounding wetlands.
The cause of the massive leak stemmed from a pump station that was undergoing maintenance at the North District Wastewater Treatment Plant, on Biscayne Boulevard in North Miami, just west of Oleta River State Park.
Jennifer Messemer, spokeswoman for the county’s Water and Sewer Department, blames the overflow on unexpected heavy rainfall combined with repairs to the pump.
Some areas of Miami-Dade and Broward got swamped with six to eight inches of rain last Saturday, leading to road flooding in areas including Aventura, Hollywood, Opa-locka and downtown Miami.
“It’s almost like a perfect storm, if you will,” Messemer said. “Unfortunately, we had one of our pumps out of commission for repair but we want to make sure we have our preventative maintenance completed before rainy season happens.”
The county’s Department of Environmental Resources Management is in charge of enforcing local, state and federal environmental standards by regulating water and sewer utility companies and monitoring water pollution. Elevated levels of enterococcus bacteria and fecal matter were found during DERM’s testing of the area waters.
The Florida Department of Health in Miami-Dade will decide, based off the readings of the results, when it’s safe for people to go back in the water. There will need to be two days of consistent clean testing for the advisory to be lifted.
Messemer says raw sewage at the treatment plant had already gone through a certain amount of cleaning treatments but that it hadn’t made it to disposal chamber before the overflow at the plant.
“It’s partially treated effluent — not raw sewage,” she said.
The process removes impurities and bacteria before it gets to a treated level.
She said that stormwater runoff, which eventually feeds into storm drains, contributed to the high levels of bacteria found by DERM, in addition to to partially treated effluent. Storm water drainage is not under jurisdiction of the Water and Sewer Department but is managed by the county’s Solid Waste Department.
Stormwater runoff occurs when rain water flows above ground, picking up debris, chemicals, dirt, and other pollutants and flow into a storm sewer system or directly to a lake, stream, river, wetland, or coastal water, according to the Environmental Protection Agency. Anything that enters a storm sewer system is discharged untreated into the water that people use for swimming, fishing and for drinking.
“The signs are still posted,” Messemer said of the warnings to keep out of the water in the contaminated areas. “Once the results are clear we will be immediately out there removing signs so that people can go back to enjoying their recreational outside water based activities.”
Repairs to the North District Wastewater Treatment Plant’s pump station are expected to be completed by Sunday. The spokeswoman said that if more rainfall is expected between now and then, it would take “about an hour” to get the pump station back in service.
For more information and updates on the advisory visit: www.miamidade.gov/water.