Waterfront property in the Florida Keys took on a new look this week with the return of autumn’s king tides that flood low-lying streets in areas from Key West to Key Largo.
Monday night, the National Weather Service in Key West expected the “mean lower low water” to measure about 2.5 feet above average. Instead, it was logged at 3.42 feet, meteorologist Christopher Rothwell said Tuesday.
It turned out to be nearly a foot higher. “So low and behold, it’s pull up your pantlegs time,” Rothwell said.
Mean low lower water, abbreviated as MLLW, is the “average height of the lowest tide recorded at a tide station each day,” according to the National Oceanic and Atmospheric Administration.
“These tides have become higher and are causing more flooding due to the impacts from sea-level rise,” said Cammy Clark, information officer for Monroe County. “The tides have averaged at least a foot above normal.
“Due to these higher tides, the water level also may not lower as fast as it has in the past,” she said. “For roads, this means flooding may occur for several days until flood waters eventually can recede.”
King tides are expected in the spring and autumn, but three primary factors — the low orbit of a full moon, water temperatures and weather conditions — can create “an anomaly” that turns normally damp areas into shallow lakes, Rothwell said.
This fall’s king tide conditions were affected by late-season hurricanes that caused steady winds from the northeast “slamming into the Florida peninsula,” Rothwell said. Those winds run counter to the north-flowing Gulfstream Current. “These storms basically jammed up the water, causing a big back-up,” Rothwell said.
Conditions may start to lessen in the next few days but could linger.
Monroe County government had budgeted about $5 million annually for routine road upgrades, but now is evaluating the effect of the higher tides from sea-level rise. An ongoing project in the Lake Surprise subdivision on Key Largo received about $250,000 in additional funding for engineering, adding storm drains and raising the height of the road, county engineer Judith Clarke said Tuesday.
“Last year we saw a lot of flooding on the bayside and the water stayed there for a long time,” Clarke said. “This year, it doesn’t seem to be staying as long but we’re seeing more flooding on the oceanside.”
Kevin Wadlow: 305-440-3206