Coastal infrastructureRising seas bring heavy burden to Florida coastal economy. Can it adapt?
Florida is a coastal state. Nearly 80 percent of its twenty million residents live near the coast on land just a few feet above sea level, and over a hundred million tourists visit the beaches and stay in beach-front hotels every year. The coastal economy in Florida is estimated to account for 79 percent of the state’s gross domestic product, a measure of direct revenue into the economy. It now is widely accepted that climate change is causing an unprecedented rise in sea levels around the world, and that locations such as Florida, where huge infrastructure and large populations live right on the coast, are especially vulnerable. An important reality is that sea-level rise is not a future phenomenon. It has been happening slowly over the past decades, at about one inch every ten years. That’s a half foot since the 1960s and already it is taking a toll.
Florida is a coastal state. Nearly 80 percent of its twenty million residents live near the coast on land just a few feet above sea level, and over a hundred million tourists visit the beaches and stay in beach-front hotels every year. The coastal economy in Florida is estimated to account for 79 percent of the state’s gross domestic product, a measure of direct revenue into the economy.
People living and working on the Florida coast face threats from hurricanes and storm surge, sometimes more than once a year. Scouring of beaches by wind and waves takes away sand, and beaches must be nourished with new sand, as often as yearly, in areas with high erosion. Miami-Dade, Broward, and Palm Beach counties now have problems obtaining near-shore, low-cost sand. This means that they will have to use considerably more expensive alternatives to native sand that may negatively impact sea turtles or beach plants, diminish the quality of the beach environment and have adverse impacts to local communities that pay for beach re-nourishment.
The threats aren’t reserved just for coastal residents. People in south Florida who live farther inland have homes and businesses on former wetlands that were drained in the middle of the twentieth century. After a heavy rainfall, canals carry water to the sea. Should those canals fail, there would be massive flooding. Those canals also maintain a freshwater “head,” or buffer, which prevents salt water from intruding into the well fields that supply drinking water to the millions of residents.
In this precarious situation, how is sea-level rise affecting coastal Florida, and what can we expect in the future?
Inches matter
An important reality is that sea-level rise is not a future phenomenon. It has been happening slowly over the past decades, at about one inch every ten years. That’s a half foot since the 1960s and already it is taking a toll. Areas of Miami now have flooding at high tide — a situation not observed in the past. The drainage system in south Florida is starting to fail. Flood control structures that take away rainwater by gravity sometimes cannot flow when the ocean side of the flood gates has a higher level of salt water than the upstream fresh water sides.
