Hurricane Irma: Everyone lines up for sandbags, but do they help?

Tampa Bay emergency agencies have already distributed more than 200,000 sand bags this week that many folks spent more than two hours in line waiting to get.

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The city of Tampa gave out more than 16,500 bags at its three locations on Tuesday alone. In St. Petersburg, a queue of people wrapped around Bartlett Park waiting their turn on Wednesday.

Deanna Stross, 33, was one of those waiting in line. She's only lived in St. Petersburg for three years and is unsure if sandbags will be enough to protect her house.

"The Bay is five feet from my back porch," she said, "and I am very nervous."

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This won't help: Experts say sand bags may not do much to protect homes. Yet residents have spent a lot of time and energy obtaining them at distribution centers set up in nearly every city and county in the Tampa Bay area.

"This is a lot of work, a lot of time and a lot of prep," said Craig Fugate, the former Federal Emergency Management Agency administrator who once served as Florida's top emergency official. "Just putting a few sand bags in front of your door, if you're talking more than just a couple inches of water, it isn't going to stop it."

There are a few problems with relying on sand bags.

First and foremost, they are not meant for people who live in evacuation zones, Fugate said. Those residents should focus their energy on finalizing their packing, determining their route and finding a safe place to stay, he said.

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Nor will sandbags do anything to stop the intense water that comes with storm surge.

"We tell residents not to rely on sandbags to protect their homes from flooding or storm surge," Pinellas County spokeswoman Irena Karolak said. "With hurricane storm surge, the best thing is to brace your home, windows and garage doors and protect yourselves."

Sand bags are only meant to be stacked a few rows high to guard against a couple inches of flooding. That could be helpful to those who live in areas which flood regularly with heavy rainfall.

But even then, they're only effective if people use them correctly. For example, placing a few bags in front of a front door won't do much in most circumstances, Fugate said.

To be most effective, the bags need to be lined around the entire home. But that's hard to do because many distribution center have a limit as to how many bags people can pick up, such as Pinellas County's 20-bag maximum.

"To do it most effectively, you've got to completely seal off all the ways water can get into your foundation and through the ground floor." Fugate said. "What the average person needs is far beyond the number of bags you're going to get from most of these centers."

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Sometimes it's good enough to just stack sandbags around the doors and garage, Fugate said, especially if it's a concrete block home.

"With wood, it's not going to help much." Fugate said. "The minute that water gets over, around or through those sandbags, then those sandbags aren't going to fix much."

So if sand bags don't do much, then why does every government provide them? One theory is that it helps people feel like they have some control in an otherwise unpredictable situation.

"Being able to do something, even if it's not the most effective thing, helps reassure people as the hurricane approaches," Fugate said.

There are other ways people can protect their homes that don't involve waiting in a long line with a shovel. Karolak suggested securing windows and garage doors. Plywood and storm shutters are often recommended.

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Those who are worried about flooding are encouraged to move furniture and valuables to a second floor, if their home has one, or elevate items.

"Stack stuff as high as you can, take your papers, pack your bags, and be ready to evacuate," Fugate said. "If you need to evacuate, don't waste your time putting out sand bags."

Times staff writer Allison Graves contributed to this report. Contact Caitlin Johnston at cjohnston@tampabay.com or (727) 893-8779. Follow @cljohnst.