King Tide Flooding New Normal for Florida Keys

Rising sea levels coupled with the impact of recent hurricanes on the Gulf Stream have left residents of the Florida Keys enduring massive “king tides” nearly three months in excess of the norm, and as much as 18 inches higher than customary, with one Key Largo neighbourhood reporting 82 days of flooding in a row.

Feeling like “trapped rats,” reports the New York Times, are residents of the tiny community of Stillwright Point, on the northern tip of Key Largo. Once dotted with fishing cottages, the Point is now lined with million-dollar residences owned by wealthy professionals and intermittently occupied by rock stars and politicians on vacation.

Navigating the high and tenacious tidewater “has become a maddening logistical task,” as residents worry about exposing the undercarriages of their vehicles to highly corrosive seawater. They’re also getting fed up with the rotten-egg smell of the virtually stagnant water.

While so-called “king tides” occur “predictably each fall, when the alignment of the moon, sun, and Earth creates a stronger gravitational pull on the warm oceans,” writes the Times, climate change is driving higher sea levels that exacerbate the flooding.

And whereas the Gulf Stream can normally be relied upon to carry water away from the Keys, meteorologists believe Hurricane Dorian and other powerful storms that swept through the region in late summer interrupted the cycle, leaving huge volumes of ocean water “backed up” all along the southeast coast of the United States, and especially along Florida’s shores. As a result, said Chris Rothwell, lead meteorologist with the U.S. National Weather Service in Key West, “tides from the Carolinas to Florida, and from the Florida Keys to Tampa, have been six to 18 inches higher than expected.”

The monstrous tides are also lasting far longer than normal: interviewed at Day 40 of this year’s event, Stillwright Point resident Emilie Stewart told the Miami Herald that king tides normally last a maximum of “three, four, five days.”

That puts the 2019 tides off the charts, with 2015 the closest contender within the memory of Stillwright Point regulars, at 22 days.

While the current level of flooding is “a high anomaly,” Brian McNoldy, senior research associate at the University of Miami’s Rosentiel School of Marine and Atmospheric Science, said it will eventually become the norm. “There’ll be a time at some point where what used to be our high tide becomes the mean sea level.”

Anticipating that reality, the residents of Monroe County, where Stillwright Point is located, want county officials to install a pump system and elevate the region’s 300-mile road network. Rhonda Haag, the county’s sustainability director, has promised to fast-track the modelling of a tide-resilient road system. But actual road-building will have to wait until the state completes other such projects, elsewhere in south Florida, “that have been in the works for years”.

And lifting vehicles out of the corrosive reach of rising seas by elevating roads will not come cheap. Haag told the Times that raising just a third of Monroe County’s roadways could cost US$1 billion.