Writing From Florida About Freshwater

February 13, 2015 – My wife and I are snow birds, Canadians who come south for part of the winter to escape snow, ice and the cold. When we get here there is one thing we don’t do. We don’t drink the water coming from the tap. Instead we buy bottled water and use it for making tea and for cooking. We’re not alone in doing this. Many Floridians have become accustomed to doing the same thing. The reason is Florida’s freshwater just doesn’t cut it for drinking. It doesn’t taste right and it hasn’t for a very long time.

Most of Florida’s drinking water, nearly 90%, comes from underground aquifers. Deep wells tap the aquifer for South Florida‘s large urban communities. On top of that South Florida gets over 150 centimeters (about 60 inches) rainfall annually. Those who manage the freshwater supply will tell you that keeping homes from getting flooded by freshwater each year remains a challenge in itself.

Much of the South Florida population resides on reclaimed Everglades’ land, land that normally would be a freshwater swamp. Residential areas here are peppered with lakes, lagoons and drainage ditches. Where we are staying close to the beach it rained last week and even here the water ponded on our street. So it would seem that with so much freshwater there should be no problem at all. But that is not the case. South Florida is booming in population. Water demand is increasing. And the wells that tap the aquifer are under siege.

Why? Take a look at the picture below. This is the rock that contains South Florida’s groundwater. It is a porous limestone. Normally one would think that rock like this would soak up freshwater like a sponge. But in fact the limestone is too easily penetrated by water. Any type of water. And that includes seawater.

You see South Florida faces another problem where seawater comes into the picture. Sea levels continue to rise off the Florida coast and the trend is accelerating. Add to that the growing freshwater demand on the aquifer and you have a perfect storm with seawater displacing freshwater in the underground aquifers of the state.

The limestone aquifer has never been a barrier to seawater. There has always been salt water in the aquifer. It just lay further down because its specific gravity is heavier than the freshwater which flowed above. But rising seas means that below ground salt water is getting closer to the surface.

So it isn’t just storm surges off the Atlantic Ocean or Gulf of Mexico that threaten South Florida. The entire ocean as sea levels rise remains a threat. The salt water is moving both inland and upward, see illustration below,  contaminating all those sunk wells dug decades ago and used by municipalities to provide drinking water.

So what’s in the cards for South Florida over the next few decades. Climatologists in studying current trends forecast a mean sea level rise of between 7.6 and 30 centimeters (3 to 12 inches). Flooding already on the increase will only get worse after heavy rains, storm surges and high tides. The water table in South Florida will creep closer to the surface posing an additional threat to homes and buildings. And of course as the water table rises salt water intrusion will further contaminate freshwater supplies.

For South Florida’s cities this is a train wreck happening at an ever increasing speed. Getting city, state and federal heads looking at the problem remains an enormous challenge. Recently I wrote about how the City of Miami Beach is addressing rising sea levels. With a limited tax base the city government has chosen to fund a storm deflection project by issuing permits to build 47 new beachfront condominium projects.  Just south of us here in Fort Lauderdale, a $11.8 million US project is rehabilitating Highway A1A after a huge storm surge generated by Hurricane Sandy in late October 2012 led to the subsequent collapse of a four-block section of the roadway. But the new storm drains and slightly raised sea wall will do little to stop what is foreecast two decades hence.

So what do you do when you have millions of people living in the Greater Miami-Fort Lauderdale area with a disaster scenario creeping towards them centimeter by centimeter? Well if you are government it appears you do the least amount and the wrong things to boot until the “shit hits the fan.”