It was the rainstorm that seemed to never end, turning roads into rivers and forcing drivers to abandon their cars in search of higher ground all over Broward County, Florida.
In Fort Lauderdale, where cars floated down streets like boats on a river, some wondered whether the city’s robust development boom made the flooding even worse.
Weary and waterlogged residents are also wondering when this might happen again. What the city is doing to make things better next time. And whether this latest nightmare flooding event might persuade city leaders to slow down the frenzied development craze.
Fort Lauderdale Mayor Dean Trantalis says one has nothing to do with the other.
“What we’re seeing here is a 1,000-year incident,” he said Thursday during a news conference. “No city could have planned for this. Let’s face it, Fort Lauderdale is a flat city. We’re surrounded by water. We’re the Venice of America. Development and stormwater drainage are two entirely different issues.”
Is the mayor’s claim true?
Not quite, experts say.
Nowhere for the water to go
Development does indeed impact flooding, said Jean-Pierre Bardet, a professor of civil engineering at the University of Miami.
All those high-rise towers, parking garages and parking lots mean there’s more concrete and asphalt covering the ground and nowhere for the water to go.
“Development increases density,” Bardet said. “It also covers the ground with parking lots. The water doesn’t infiltrate into the ground. And guess what, you get floods.”
If Fort Lauderdale wasn’t paved over with so many buildings and parking lots, the flooding wouldn’t have been nearly as bad, said Ralph Zeltman, a retired county engineer who serves on Fort Lauderdale’s Infrastructure Task Force.
“The more parking lots you have the more the water will pond and stay, with nowhere to go,” Zeltman said. “It doesn’t take a genius to figure that out. The rainwater cannot be absorbed by parking lots.”
Fred Bloetscher, a civil engineering professor at Florida Atlantic University in Boca Raton, agreed.
“The more asphalt you create, the more you need a place for water to go,” Bloetscher said. “And if it doesn’t have a place to go, it’s just going to rise. The mayor’s probably right in saying you can’t really plan for a storm like this. But the development is going to make the flooding a little worse — or maybe a lot worse.”
John Roth, a Fort Lauderdale activist and member of the local group Lauderdale Tomorrow, questioned the wisdom of allowing so many high-rise towers to be built on the barrier island and other flood-prone areas.
“Everybody in the Caribbean knows you don’t build a house in a river basin because the rains will wash the house away,” he said. “Here we have swamps and lowlands. And they continue to give permits to build towers in flood-prone areas. People think they can outwit nature. But the rain is going to come and you have to mitigate for that.”
‘Hard to predict nature’
What if you could turn back the clock and bring back the green spots paved over by asphalt?
“I would say you would not have seen all this flooding,” Bardet said. “It is true that 26 inches of rain fell in a short time frame, so it really pushed the limits of the drainage system. But what’s happening is we are constructing more and more and creating more impervious surfaces in our urban areas. That leads to more runoff.”
Now some are wondering when it might happen again.
Critics scoffed at the claim that this week’s extreme flooding was caused by a 1,000-year storm.
“It’s ridiculous to call this one a 1,000-year storm,” Zeltman said. “You might as well call it a million-year storm.”
Roth also has his doubts.
“They can call it a 1,000-year storm, but it could happen again next year,” Roth said. “The 1,000-year storm claim is a political escape route designed to make people feel safe.”
Will we see another flood like that in our lifetime?
“It’s really hard for me to predict nature,” Bardet said. “But if we don’t do anything about our drainage system, my answer would be yes. If we change our drainage system, we can do something to fix it. But we need the will of our elected officials to spend the money to do that.
“The county would need to take the lead on that. Water doesn’t know political boundaries. You need coordination between several cities.”
To overcome its flooding challenges, Fort Lauderdale is already spending millions on its infrastructure, the mayor says.
“This storm has highlighted the importance of continuing our municipal efforts to address climate resiliency and upgrade critical infrastructure,” Trantalis told reporters this week. “We are in the midst of a five-year, $200 million plan to alleviate vulnerabilities, focusing on our most flood-prone areas.”
The mayor described the plan as the largest investment in stormwater and flood control in city history.
The long list of planned improvements includes raising seawalls, improving stormwater and flood-control systems, installing more tidal-control valves and drainage pipes, building new outfall connections and drainage structures, creating new catch basins, rebuilding swales and constructing stormwater reserves.
Next generation
But will that be enough to keep up with demand as more and more towers get built?
Probably not, Bloetscher said.
“When you get that kind of rain, there’s not a whole lot anyone can do to solve that,” he said. “We don’t design stormwater systems to handle 25 inches of rain. Nobody designs for this type of storm.”
Should they?
“That’s a cost-issue question,” Bloetscher said. “If you did, you’d have infrastructure that you’d need every 10 years. Is that important? Some people might think so. But that’s not for me to decide.”
The question that needs answering is what kind a rainstorm do they want the drainage pipes to handle, Bloetscher said.
“Are they trying to deal with 3 inches of rain or a foot?” he asked. “I guarantee they’re not trying to deal with 2 feet. It would cost too much money and when you really need it, it wouldn’t work too well because it would fill up with sediment. When you have really big pipes they just fill up with sand because there’s not enough water moving through them.”
Bardet predicts changes in the way we design our drainage systems.
“After what we’ve seen, people are going to go back to the drawing board and see where the weaknesses are,” he said. “If we design it the way we did in the past, we will have the same thing happen again.
“If we change the design, we can mitigate the effects of flooding on our economy and on our people. We need to look at the next generation of drainage systems. They will tell you where the water is going to go and where the water will accumulate. And you can use emergency pumps to move the water to prevent flooding.”
