A man walks in floodwaters where the vast Tulare Lake once existed outside Corcoran, California. Photo / Mark Abramson, The New York Times
Climate change is intensifying both hurricanes and everyday storms, making flooding events both more common and more severe.
When heavy rain falls, it can overwhelm streams and streets with little to no warning, both along coasts and inland.
All it takes is 6 inches (15cm) of fast-moving water to knock over an adult, according to the United States National Weather Service.
Most cars can be swept away in as little as a foot (30.5cm) of water.
Beyond the risk of drowning, floodwaters are often full of sewage, medical waste, industrial chemicals and more.
And even after the storm is over, many hazards can remain.
What’s in the water?
Floodwaters are “a toxic brew of pesticides, toxins, petroleum, anything and everything that you can imagine”, said Dr Robert Glatter, an emergency physician at Lenox Hill Hospital in New York City.
Hundreds of types of bacteria and viruses can contaminate the waters, he added, making them dangerous to play in or simply walk through.
This is especially true in the first 24 hours of a storm, when heavy rains wash out waste and trigger the “first rush of pathogens”, said Natalie Exum, an environmental health scientist at the Johns Hopkins Bloomberg School of Public Health.
Potential consequences include gastrointestinal illnesses such as E. coli, respiratory illnesses such as Legionnaires’ disease and skin infections including necrotising fasciitis, known as flesh-eating disease.
Experts strongly advise avoiding floodwaters if you can.
Keeping your mouth closed might not be enough to protect you, as you can also get sick if water gets into your eyes or ears.
And any open wound, even an insect bite or a nick from shaving, can let bacteria into the bloodstream.
Wading through floodwaters can also lead to injuries, said Dell Saulnier, an assistant professor at the Karolinska Institute in Sweden who studies global disasters and health.
Debris can be hidden, and dirty waters can conceal power lines, too, making electrocution another serious concern.
Preparation is key, including heeding evacuation orders and having at least five days of supplies in your home so you can avoid venturing out.
What protection works?
If you have no choice but to go through a flood, wear pants, long sleeves and waterproof boots, Exum said. Goggles and gloves can also help.
Cover any open wounds, even minor ones, with waterproof bandages. If a wound gets wet, quickly disinfect it with soap and clean water. If that’s not possible, use hand sanitiser and wet wipes so that pathogens don’t fester.
Afterwards, clean any clothes contaminated with floodwaters on the hottest water setting and with a disinfectant like bleach, said Dr Peggy Duggan, the chief medical officer of Tampa General Hospital.
“I wouldn’t say you have to throw them away, although I personally would,” she added.
What happens after the water recedes?
Even after floodwaters drain away, trees, homes and debris will remain drenched, said Dr Mark Morocco, a professor of emergency medicine who practices at Ronald Reagan UCLA Medical Centre.
“Imagine that somebody had sprayed your entire neighbourhood with raw sewage,” he said.
Mould can grow quickly under carpets, in cabinets and on drywall and fabric furniture.
The spores can be drawn deep inside the lungs, posing a particular threat to older adults, immunocompromised people and those with respiratory conditions such as asthma and chronic obstructive pulmonary disease.
Dr Jamie Garfield, a pulmonologist at the Temple Lung Centre and a spokesperson for the American Lung Association, advises patients with these conditions to watch out for worsening symptoms, and to hire cleaning professionals if possible — or ask friends for help.
“If you spend an hour cleaning off an area of your home and you start to notice some chest tightness or coughing, that’s an indication to lay off,” Garfield said.
Pathogens and chemicals can also seep into drinking water. So, stick to bottled water or boiled tap water when you drink; brush your teeth; or wash your hands, dishes and produce.
After local officials give the all-clear, it’s a good idea to let the water run for a while to flush the pipes of any residual gunk, Exum added.
While mosquitoes often get whisked away by the initial flooding, they tend to return after a week or two, said Dr Stephen Liang, an infectious diseases physician at WashU Medicine in St Louis.
Pockets of standing water can quickly become breeding grounds for them, so try to clear puddles, empty buckets and unclog drains. And when outside, protect yourself with long sleeves and insect repellent.
This article originally appeared in The New York Times.
Written by: Simar Bajaj and Maggie Astor
Photograph by: Mark Abramson
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