One morning in June 2018, Douglas Yoder climbed into
a white government SUV on the edge of Miami and headed northwest, away
from the glittering coastline and into the maze of water infrastructure
that makes this city possible. He drove past drainage canals that sever
backyards and industrial lots, ancient water-treatment plants peeking
out from behind run-down bungalows, and immense rectangular pools
tracing the outlines of limestone quarries. Finally, he reached a locked
gate at the edge of the Everglades. Once through, he pointed out the
row of 15 wells that make up the Northwest Wellfield, Miami-Dade
County’s clean water source of last resort.
Read more at: Miami Will Be Underwater Soon. Its Drinking Water Could Go First
Yoder, 71, is deputy director of the county’s water
and sewer department; his job is to think about how to defend the
county’s fresh drinking water against the effects of climate change. A
large man with an ambling gait, Yoder exudes the calm of somebody who’s
lived with bad news for a long time.
“We have a very delicate balance in a highly managed
system,” he said in his rumbly voice. “That balance is very likely to
get upset by sea-level rise.” What nobody knows is when that will
happen, or what happens next.
From ground level, greater Miami looks like any
American megacity—a mostly dry expanse of buildings, roads, and lawns,
sprinkled with the occasional canal or ornamental lake. But from above,
the proportions of water and land are reversed. The glimmering
metropolis between Biscayne Bay and the Everglades reveals itself to be a
thin lattice of earth and concrete laid across a puddle that never
stops forming. Water seeps up through the gravel under construction
sites, nibbles at the edges of fresh subdivisions, and shimmers through
the cracks and in-between places of the city above it.
Miami-Dade is built on the Biscayne Aquifer,
4,000 square miles of unusually shallow and porous limestone whose tiny
air pockets are filled with rainwater and rivers running from the swamp
to the ocean. The aquifer and the infrastructure that draws from it,
cleans its water, and keeps it from overrunning the city combine to form
a giant but fragile machine. Without this abundant source of fresh
water, made cheap by its proximity to the surface, this hot, remote city
could become uninhabitable.
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.
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.”
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