Florida’s coral reefs dying
We’re murdering Florida’s coral reefs. And not just with the suicidal pretense that the world has no pressing need to curb global warming.
Of course, the reefs, like much of the world’s flora and fauna, are indeed cooking. In January, NOAA reported that the globe’s five warmest years on record had come in the 2010s; that the 10 warmest years had been recorded since 1998; the 20 warmest since 1995. (And 2018, thus far, has scorched the world with a cascade of record-setting heat waves.) Marine scientists blame the heat for devastating incidents of coral bleaching. Reefs need a stretch of normal temperatures to recover. It’s not happening. (Meanwhile, the ocean has been absorbing tons of the carbon pollution out of the atmosphere, creating carbonic acid that eats away at the reef structure.)
But there’s also a less esoteric, perhaps even more devastating pathology causing reef losses, particularly for the ridges closest to shore, according to Brian LaPoint, chief investigator with Florida Atlantic University’s Harbor Branch Oceanographic Institute. “The science clearly shows that the global warming is only part of the story.”
Professor LaPoint cited nutrient pollution — a polite term for the effluent and storm water runoff South Florida flushes into the water — as the likely reason only a fraction of Florida’s coral reefs still survive.
Two years ago, team of Australian and American researchers reached back in history to measure extent of reef loss in the Florida Keys. They compared nautical charts commissioned by the British admiralty in the 1770s to modern day satellite photos.
According to their findings, published in the journal Science Advances, the historical observations were surprisingly accurate when juxtaposed against modern satellite-based surveys of Florida’s coral reefs. The naval charts also revealed that more than half “of the historical coral observations are in locations where coral habitat does not exist today.”
Ninety percent of the reefs that the old charts located near the shoreline has simply vanished, replaced by sea grass and mud. LaPoint posits that the nitrogen-rich effluent spilling out of South Florida’s coastal cities makes corals more susceptible to bleaching and disease. And that the stuff nurtures algae blooms that can essentially smother the reefs.
LaPoint puts no small part of the blame on South Florida’s four outfall pipes — two in Broward, two in Miami-Dade — that discharge 188 million gallons a day of treated sewage a mile or more out at sea. (Palm Beach County has discontinued use of two outfall pipes, except after heavy rains that overwhelm the county’s sewage treatment plants.)
State law requires that the counties cease use of the outfall pipes by 2025. LaPoint thinks that’s not soon enough.
But replacing the outfall pipes will be wildly expensive. State legislators envisioned South Florida diverting recycling treated wastewater to water golf courses and lawns. But the combination of old, leaky sewer pipes and coastal saltwater intrusion — another harbinger of global warming — makes it very costly to remove the salt and raise the water to irrigation standards, according to Jennifer Jurado, who oversees regional climate resilience planning for Broward County.
Miami-Dade alone figures the cost of complying with the state law could exceed $5 billion. The state has offered no financial assistance. “An unfunded mandate,” Broward Mayor Beam Furr calls it.
Furr notes that even if the wastewater treatment plants could convert the sewage to potable water, state law would still prohibit use of the outfall pipes. Other alternatives for disposing of the treated water jack up the costs by hundreds of millions of dollars. Furr suggested that the state divert a portion of the Amendment One land conservation money toward the massive costs associated with shutting down the outfall pipes. Legislators, however, regard that pile of money as a kind of slush fund for pursuits unrelated to Florida’s neglected environment.
Besides, Jurado suspects that the outfall pipes, which extend beyond the reefs, may not be the main culprit in the reef die-off. She talked about a “massive amount of urban runoff ” — stormwater that washes fertilizer, animal waste and other pollutants into Broward waterways. Maybe worse, Broward County has some 67,000 homes and businesses that still rely on septic tanks — a system that depends on backyard drainage fields to absorb and filter household effluent.
Jurado said that a rising water table will defeat septic tank systems. And she’s sure that many of them are already failing, allowing unfiltered sewage to seep into county’s waterways and out to the ocean. It didn’t help that Florida repealed (after just one year) a 2010 law requiring septic tank inspections every five years.
One way or another, we’re killing Florida’s coral reefs, the only tropical reef formation in the United States, stretching 340 nautical miles, from the Dry Tortugas, along the Florida Keys, north to the St. Lucie Inlet in Martin County. The idea of stopping their degradation, at least from sewage pollution, doesn’t require lofty tree-hugger sensibilities. The economics alone ought to convince even the most miserly conservative. NOAA estimates that Florida’s coral reefs generate about $6 billion a year in sales and income.
They just might be worth saving.