Spotlight on Infrastructure: Miami

Between the sun kissed beaches, palm tree lined avenues, and art deco architecture, life in Miami seems to be every bit ideal,; but when it comes to the city’s water supply, things are shaping up to be anything but. A set of complex situations put this beachside city in unique danger when it comes to rising sea levels, and the implications can go deep. Let’s take a look at exactly what is putting Miami in harm’s way, and surprising things that could mean for the water supply.

The Rising Tides

Rising sea levels are a problem just about everywhere. We all know the stats: hundreds of cities, like Oakland and Cambridge, MA will be underwater, coastal flooding will become a major chronic problem, and higher sea levels will worsen storm surges, reshaping the way that cities like New York deal with the growing number of storms. What you may not know, is that one of the locations most at risk for these effects is Miami.

To start, Miami is low lying -- simply put, the city sits right beside the sea at a low elevation, and thus it is at constant risk of flooding. But the city’s unique geology is a far more dastardly culprit. Miami lies on limestone, which is made up of eons of coral life that’s been compressed into rock over time. The problem is, that this rock is porous, full of tiny little holes that let the water pass through. As one local expert put it “Our underlying geology is like Swiss cheese” and because of that the water just pours through. Already, some Miami neighborhoods are seeing regular flooding on perfectly sunny days bubbling up through the ground when the tides are simply high.

There’s also the issue that due to the combination of Miami’s location and nearby ocean currents, sea levels seem to be rising especially quickly in South Florida, estimated to be at 6-10 inches above their 1992 level by 2030. And with higher sea levels come higher tides – if the sea’s baseline level is higher, their tides will be too.

Altogether, Miami’s imminent flood risks are unquestionably bona fide, but these all carry with them another bigger risk: groundwater contamination.

The Invader at the Gates

One of the greatest public health risks that Miami residents will soon face is one you’ve probably never heard of: Saltwater Intrusion.

With sea level rise bringing forth floods on a regular basis, Miami’s water supply is at constant risk of contamination. While the public water supply is comprised of healthy freshwater, these floods bring with them untreated salty seawater. When the city’s precious water sources, such as the vital Biscayne Aquifer, come into contact with the ever progressing saltwater, they become contaminated and undrinkable.

This oncoming crisis is nothing short of massive, with the Miami Herald opinion board warning that “Miami-Dade County already relies on western wells to keep providing fresh water. Broward County within 50 years expects to lose 41 percent of its coastal well field capacity to the underground push of saltwater.” These water sources are absolutely critical to the survival of South Florida’s communities, and action is already being taken.

Desalination plants are being built, which will convert this seawater into a potable form. Recycling programs are also being planned to help preserve the precious water that the region already has. Major public works project are in the works that will help to abate the oncoming sea water, such as building mangrove forests and pumping out incoming water back into the sea. Finally, new wells and water sources are being explored that can provide precious new sources for the city’s freshwater needs.

Ultimately, every community exists within a unique place, with a unique set of infrastructure and a unique set of demands. Miami may be under threat, but a proactive community is building their first lines of defense and working to preserve the city’s water future. Hopefully they can prove a model of prevention and rescue that cities around the world can come to follow.