Construction sites across Charlotte will be on high alert next week as Hurricane Irma potentially moves into the Carolinas, and tower crane operators are keeping a close eye on the storm.
Tower cranes – the big, semi-permanent cranes installed on construction sites that have become practically a symbol of the building boom – have multiplied along with the new apartments, hotels and office buildings going up. There are about 15 tower cranes installed across the city, most of them clustered in and around uptown.
With their swinging metal arms and big counterweights perched on skinny metal frames, tower cranes might look vulnerable. But Jason Kenna, general manager of crane company Heede Southeast, said they’re designed to withstand a sustained Category 3 storm. That means winds of about 111 to 129 mph, according to the National Hurricane Center.
“We’re keeping an eye on it,” Kenna said. Heede Southeast is operating about a dozen tower cranes in Charlotte, at construction sites including Crescent Stonewall Station uptown and at Charlotte Douglas International Airport. But he’s not concerned about the cranes in Charlotte, which would not take a hit from a Category 3 storm even in the worst forecasts.
Kenna said Heede Southeast is sending crews this weekend to take the top sections off tower cranes in Charleston and Wilmington, as a precaution.
The city of Miami warned residents to stay away from tower cranes during the storm, which could exceed the cranes’ specifications if Irma crashes into south Florida at full strength. There are up to 25 cranes up now in Miami, the city said.
If Irma does swipe at Charlotte, Kenna said the cranes would be shut down, along with the rest of the city’s construction sites.
“It would be too windy for us to do anything safely,” he said. “All the job sites would be shut down.”
The crane arms would be allowed to rotate freely with the wind, like a weather vane, Kenna said. That’s the same procedure they take during normal storms when the wind gets too high for them to operate. Their legs are bolted into concrete bases 7 or 8 feet deep, giving them enough strength to lift and withstand thousands of pounds of force.