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5th January 2021
...continued from PART 1

More worrisome than the mining itself is the whole vast world of toxicity to which the mining has opened up the aquifer. “The rock belt is going to become a place where contaminants can enter and move deeper,” says Philip Stoddard, the mayor of South Miami, one of the cities in Miami-Dade County that’s most exposed to sea-level rise. As flooding and rainstorms get worse, Stoddard warns, they’ll move surface water around the county in increasingly unpredictable ways. “You’ve always been able to count on the water going west to east,” drawing runoff away from the water supply, he says. “What happens when it starts going back toward the wellfield? You don’t have to be a genius to figure out it could be a bad thing.”

Then there’s the feces. As developers built out Southeast Florida, they found that instead of connecting each new home to the local sewer system, it was often easier to install septic tanks. Miami-Dade has about 90,000. “It was the magic carpet for quick, cheap development in Florida,” says Brian Lapointe, a research professor at Florida Atlantic University who focuses on the role of septic tanks in water contamination. These tanks are typically used in rural areas where homes are too far apart to justify connecting them to a central sewage system—but also in places where residential construction happens faster than municipal infrastructure development. Septic tanks trap solid waste, which is supposed to be pumped out, while the liquid stuff drains into the soil, where gravity and time filter out bacteria and whatever else is in it before it reaches groundwater. In Southeast Florida, that groundwater is especially close to the surface—and rising.

The state requires at least two feet of dry soil between the bottom of the drainage field and the top of the water table, but Lapointe says that during the wet season, the groundwater in parts of southern Florida already comes above that two-foot threshold. More intense flooding and rainstorms will swell the water table further, on top of the gains caused by sea level rise, sending partially treated human waste into the aquifer. That waste can contain E. coli bacteria, which cause diarrhea, vomiting, and even kidney failure. High levels of nitrates, another component of untreated waste, cause what’s called blue baby syndrome, in which infants’ blood can no longer carry sufficient oxygen.

Lapointe adds that one of the ways researchers track septic-tank contamination is by tracking the levels of acetaminophen in the groundwater. “People’s medications are coming with that septic-tank effluent.” The wonders of the human digestive system are many and varied, containing any number of other bacteria and viruses—“all these other organic compounds that may or may not be affected by the treatment at the utility plant,” he says.

How long does Miami have before the water table overwhelms the septic system? Officials, including the South Miami mayor, worry that the point of failure is closer than people realize. Says Stoddard, “I’m convinced that some of those septic systems are working by force of habit rather than by the laws of physics.”

* * *

The slowest-moving threat to Miami’s drinking water is also the most sweeping: As the ocean rises, salt water is being pushed into the limestone, forming a wall of brine that’s creeping inland along the aquifer’s floor. The county’s wells are essentially giant straws drawing water from 60 feet to 80 feet beneath the ground. As the saltwater front advances westward across the aquifer, reaching each of those intake valves and enveloping them in saline water, it risks rendering them useless in succession—a sort of Sherman’s March in reverse, as prosecuted by the sea.

Projecting the pace of saltwater intrusion is fantastically complicated, all the more so because the state and federal governments are still debating whether and how to proceed with a massive, still-unfunded pledge to restore the Everglades. Doing this could increase the flow of fresh water into the aquifer and thus slow the salt line’s inland creep, but the uncertainty means the county’s plans extend only through 2040, by which point Yoder and others officials say they should still be able to use all but one of their current wellfields. Regardless of the pace of seawater incursion, the Northwest Wellfield, almost 20 miles inland, will be one of the last to succumb; short of cutting into the Everglades, there’s no farther to go.

Except farther down. In 2013 a new facility west of the Hialeah treatment plant began pulling brackish water up from 1,000 feet beneath the surface, below the Biscayne Aquifer, then pushing that water through a series of plastic membranes, a desalination process called reverse osmosis. The process requires as much as 200 pounds per square inch of pressure, which consumes about 5,000 kilowatt-hours of electricity per million gallons of water.

Though far from perfect, desalination may one day be Miami’s only option. Climate advocates fret that the increased need for desalination will accelerate global warming. For the county, there’s a more urgent concern: Reverse osmosis is enormously expensive. Water from the plant, built by engineering company AECOM for $55 million, costs two and a half times as much to process as water from the Biscayne Aquifer.

Hypothetically, most of the challenges climate change poses to Miami’s drinking water could be solved with money. Homes with septic tanks could be connected to the sewer infrastructure, a process Yoder estimates would cost from $2 billion to $3 billion. The soil at Superfund and other industrial sites could be dug out or better encased. Real-time monitors could be installed to warn of unexpected seepage. Still more advanced technology could be installed at water-treatment plants. But those projects would need funding. And there’s already a long line.

In 2008 the Florida legislature passed a law dictating that the state’s water utilities stop discharging sewage into the ocean by 2025; complying with that timeline could cost as much as $5 billion, Yoder says. Then, in 2013, Miami-Dade entered into an agreement with the EPA, which had found the county unlawfully discharged more than 28 million gallons of untreated wastewater into Biscayne Bay. The county promised to upgrade its wastewater collection and treatment facilities at a cost of $1.6 billion.

In its 2015 capital budget, Yoder’s department estimated that $13.5 billion would be required for these and other future infrastructure projects, of which $9.5 billion would be funded by bonds. But last November, Moody’s Corp. warned that the county’s creditworthiness depends on “future annual rate increases to meet escalating debt service requirements”—saying, in effect, that the county’s elected officials who must approve rate increases had better be willing to accept the political pain associated with ratcheting up their voters’ water bills. If not, the county’s credit rating could fall, necessitating higher interest payments on its bonds—and even higher water bills to cover them.

The county’s crush of climate-related spending requirements goes beyond protecting drinking water. Add to that the cost of pumps and sea walls as rising seas turn the area’s gravity-reliant drainage canals back on themselves. “Anything that this county relies on that is gravity-based is in jeopardy with sea-level rise,” says Wilbur Mayorga, head of environmental monitoring and restoration at the county’s Department of Environmental Resources Management. “We’ve been lucky all this time. The time will come that it may not be so easy.”

Spending on that scale is hard for any county to manage on its own. The challenge is greater here: Despite pockets of extreme wealth—one study estimated that the Miami metro area has the nation’s eighth-highest number of millionaires—the county overall is poor. Its median household income of $44,224 is almost one-quarter lower than that of the country as a whole.

Asked if the state would help Miami-Dade protect its drinking water from climate change, Governor Rick Scott’s office directed questions to the Florida Department of Environmental Protection, which said in a statement that it “continues to work to protect the resiliency of our coastal ecosystems and shoreline communities.” But José Javier Rodríguez, a Democrat who represents Miami in Florida’s Republican-held senate, says his city is unlikely to get bailed out by the state. It’s not a question of believing in science. “The massive political and institutional resistance to taking action, in my view, is not largely ideological,” he says. “It’s not largely even political. It’s a question of being intimidated by the price tag.” As the low-tax state struggles against a revolt among school districts protesting meager budget increases and a $28 million prison funding deficit, there’s no appetite for funding the solutions to future crises, even when the future is almost here.

The obvious solutions would cause problems of their own. Why not stop mining near the wellfields, for instance? Because the limestone from those mines goes into the concrete used to construct sea walls and build higher off the ground around Florida’s coast. There’s little disagreement about the need to get rid of the septic tanks, but which homes get help first? If a coastal neighborhood will have to be abandoned anyway, is it worth spending money on new sewers?

Now pull the lens back further. Miami’s drinking water problems are merely one facet of the still-accumulating effects of climate change that officials must identify, decipher, and combat. These include new diseases such as Zika, more frequent toxic algae blooms, disappearing beaches, heat waves, the growing threat of a real estate crash, and the eventual need to relocate people away from the coast. Protecting the aquifer isn’t the end of adapting to climate change; it may not even be the hardest part. It’s simply the price the city will have to pay to keep trying.

That leaves the cruelest lesson of climate adaptation: The costs of saving Miami will mostly fall on the people who live here—testing how much they’re willing to pay for the privilege, a sort of free-market Darwinism for the life of whole cities. “There will always be drinking water here,” says Virginia Walsh, a hydrogeologist with Yoder’s department. “It’s just a question of how much you want to pay for it.”

Stoddard, the South Miami mayor, says the people who already have homes here will accept almost any price to stay. But those who would otherwise come to South Florida will start looking at the growing cost of protecting it—measured in water rates, in property taxes, in insurance premiums, in uncertain future home sales—and go elsewhere.

“People will hang on with their fingernails to keep what they’ve got,” Stoddard says. “But who’s going to move here? And that’s what’s going to kill us.”