A Dying Biscayne Bay

On a recent Saturday, a half-dozen people standing along the riverbank at Manatee Bend Park cast fishing lines and nets into Little River Canal. Mullet leapt out of the water, ducks skimmed the surface and iguanas sunned themselves on the seawall. Less than a mile away, by the South Florida Water Management District’s S-27 floodgate behind Midpoint shopping plaza, cormorants perched on buoys to dry their wings while manatees poked their heads above the water and nibbled the grass and weeds sprouting from the riverbank.

And, in the air, a constant insect-like hum, emanating from a four-propellered drone hovering above Little River in Miami’s Upper East Side neighborhood. Operating the drone was Daniel Padilla Ochoa, an urban planner and environmentalist who works for Ocean Conservancy, a nonprofit headquartered in Washington, D.C., that advocates for cleaner oceans and waterways across the globe. On this particular Saturday of Oct. 17, Padilla Ochoa was using the drone to take aerial shots of Little River Canal and its surrounding area.

“There is wildlife here … from an urban context, it is pretty diverse,” Padilla Ochoa said. But that has more to do with “the resiliency of the animals” residing in the river, as opposed to the overall health of the stream, he noted, pointing out the amount of pollution caught by the trash nets near the S-27 flood control device. “When you are seeing the manatees waiting to pass the load controller further upstream, they don’t look healthy,” he said. 

Padilla Ochoa and dozens of other students, scientists, volunteers and county officials were studying the effects of the king tide event as part of Florida International University’s Sea Level Solutions Day. In past years, participants primarily looked at salt-water levels in freshwater canals, puddles on land and brackish Biscayne Bay from Virginia Key to Arch Creek. 

But this year, volunteers were also looking at fecal matter levels. That’s because Biscayne Bay has been experiencing massive fish die-offs in recent months. 

Fertilizer and excrement are being at least partly blamed for it, and according to scientists, tributaries that slice through Miami-Dade County – like the Miami River, Little River, Biscayne Canal and Snake Creek – are delivering a lot of it directly into Biscayne Bay. A large share of these pollutants may be carried by Little River Canal, a natural waterway that was intentionally dredged 100 years ago to drain Miami for development. 

“There is industrial runoff, yard waste, too many fertilizers, septic tanks, all of that is affecting the water quality that is flowing into the bay,” said Kristen McLean, an El Portal resident and co-founder of the Little River Conservancy. 

Todd Crowl, director of Florida International University’s Institute of Environment, said Little River as well as Biscayne Canal “continue to pop up as red flags.” And while the cooler weather will improve Biscayne Bay’s overall conditions in the short term, Crowl warned that fish kill events will occur again.

“The bay is really dying, down to the last gasp,” Crowl said.

Struggling to Breathe

Gasp is the appropriate word. Simply put, fish kills are the end result of an environmental chain of events known as eutrophication that begins with nutrient pollution, such as fertilizer runoff, then leads to algae blooms and plant life decay, and ends with seriously depleted oxygen levels in the water. The lack of oxygen is what’s ultimately deadly to aquatic life.

Chris Langdon, a University of Miami professor with the Rosenstiel School of Marine and Atmospheric Science, said the sudden drops in oxygen take place at night and within a period of a few hours. The fish kill event in August, for example, was preceded by the detection of less than 1 milligram per liter of oxygen near Morningside Park.

“Six to 8 milligrams per liter is typical for summertime,” Langdon explained, adding that “anything below 2 milligrams per liter is considered highly stressful for marine life.”

On Oct. 20, the Miami-Dade County Commission approved more than 60 recommendations made by the Biscayne Bay Task Force to improve Biscayne Bay’s environmental conditions. Those recommendations include the county hiring a chief bay officer and forming a permanent, intergovernmental Biscayne Bay Watershed Task Force that will help coordinate funding and legislation geared toward remediating the bay.

Additionally, the county commission is moving forward with an ordinance regulating the use of fertilizers. Among other things, the code will ban the application of fertilizers containing nitrogen and phosphorus on landscaping plants and turf from May 15 to Sept. 30, or during heavy rain events. Violators will be fined $50. The ordinance is expected to come before the commission for final approval on Nov. 19.

But excess fertilizer is just part of the problem; there’s also sewage pipe leakage, stormwater runoff and septic tanks.

The Septic Tank Issue

Septic tanks are likely a large source of the fecal matter found in Biscayne Bay, noted Aaron Stauber, a researcher for Miami Waterkeeper, a local environmental group. Stauber noted that Little River, Biscayne Canal and Snake Creek happen to run through places like western Miami-Dade as well as El Portal, Miami Shores, Biscayne Park, Biscayne Shores, North Miami Beach and Ojus, where around 40,000 homes and businesses aren’t hooked up to a sewer system. Instead, they use septic tanks, a traditionally underground storage unit where wastewater flows and, over time, leaches into the ground. 

Septic tanks need bacteria found in soil to function properly. But, thanks to rising water tables, septic tanks in low-lying parts of the county are backing up. According to a November 2018 report by Miami-Dade County and the Florida Department of Health, there are already 58,000 properties with septic tanks that may be experiencing periodic failures. Among those homeowners with defective septic tanks was McLean, who lives near Little River. Last year, she had to purchase a new above-ground septic tank and bury it beneath a mound of dirt. Five of her neighbors in Soars River Estates were forced to do the same. By 2040, there may be 67,000 compromised septic tanks in Miami-Dade.

But Stauber, a graduate student at UM’s Rosenstiel School, said the problem isn’t necessarily from broken septic tanks. Septic tanks that work just fine ooze nutrient-rich affluent beneath the ground, he pointed out, and in 1970, the Federal Water Quality Administration, a precursor to the EPA, urged Miami-Dade to hook everyone up to a sewer system due to the region’s elevated water table.

“They basically said to the county, ‘You have to get rid of 170,000 septic tanks … They don’t work in South Florida,’” Stauber said. 

Today, there are still more than 100,000 septic tanks in Miami-Dade, and switching to a sewer system will be expensive. A 2016 county report estimated it would cost $3.3 billion to hook up just 83,000 homes to a sewer system. Part of that cost will fall to the homeowner. According to Homeadvisor.com, it costs between $1,279 and $4,900 to connect to a sewer line. That doesn’t include the tens of thousands of dollars needed to update a home’s infrastructure, including the removal of the septic tank, or to pay for extending a sewer line. As of press time, a new, anticipated septic tank and sewer study had not yet been released by Mayor Carlos Giménez. 

In the meantime, Crowl said scientists and officials from Miami-Dade and the South Florida Water Management District (SFWMD) will be analyzing data collected from the bay and canals to figure out which areas need to start abandoning their septic tanks.

“This is our biggest challenge. To figure out where the most vulnerable systems are and at the highest densities,” Crowl declared. “We got to help our managers and policymakers prioritize, to figure out which neighborhoods to tear up and get rid of septic tanks first.”

Crowl opined that it might be fair to ask someone living in an affluent home in Coral Gables to pay for extending a sewer line, but not so much a household that makes below $50,000 a year.

“We have a social justice issue associated with this,” he said. 

The impact on homeowners has worried county commissioners, too. During its Oct. 20 meeting, they discussed potentially partnering with a nonprofit to reduce costs to residents, similar to the septic tank replacement program initiated by Martin County. 

Rising and Problematic Water Levels

Aside from septic tanks, the high concentrations of nutrients entering Biscayne Bay may also have to do with the unusually high levels of water flowing out of Little River, Biscayne Canal and Snake Creek. 

The SFWMD, which influences the amount of water traveling through the canals through its flood control devices, did not return a phone call and email from the Biscayne Times by press time. Langdon, though, said the state agency told him that the enhanced water flows have to do with recent downpours and flood events. But the UM professor said that claim just doesn’t hold water, at least when it comes to Little River. Since April the water flows at Biscayne Canal and Snake Creek have increased by 30%, which correlates with storm events. The Miami River’s water flow hasn’t increased at all. But the Little River Canal’s water flow is 300% higher than usual. 

“The water flow out of the river is three times higher than it has been the previous 20 years, and it came on very abruptly,” Langdon said.

A lot of Little River’s water is very low in oxygen, he added. He’s less sure about the oxygen content in the other waterways. Unlike Little River, there aren’t sensors in Biscayne Canal and Snake Creek.

“There is a history of problems in Little River, and a reason to spend the money to put the sensors there,” Langdon said.

But if the oxygen is so low in Little River, why do fish still swim in it? 

Langdon explained that most of the fish there have adapted to the river’s conditions, and tend to swim on the surface where the oxygen levels are higher. But, Langdon added, “I’d be terrified to eat any fish caught there.”

For its part, the SFWMD has been trying to tidy Little River.

“You see the river cleanup boats almost every day right now,” said McLean, although she still spots plenty of solid waste floating by. She’s glad scientists have zeroed in on Little River as a watery highway for pollution into Biscayne Bay, and she’s hopeful that the river will receive even more interest now.

“It’s a historic waterway. It deserves some love. It’s unfortunate that it had to get to this point to get the attention it required,” she said. 

But Padilla Ochoa, Ocean Conservancy’s Miami-based manager for statewide partnerships, is less optimistic about the overall future of Biscayne Bay. He noted that oxygen levels would not drop as much in the bay if it wasn’t for the loss of seagrass over the course of decades. 

“Miami is a shitty town, he said. “We just let it go for too long.”