Why Cold Water in the PNW Is More Dangerous Than It Looks

Washington’s ocean, lakes and rivers are unrivaled in their beauty, but they can be deceptively dangerous, especially in spring and early summer.  

Beth Ebel, MD, is a pediatrician at Harborview Medical Center and a professor of pediatrics at the UW School of Medicine who researches injury prevention, so she knows this well.

Still, she wasn’t prepared for the scare she got when she learned that a wave had knocked her college-age son out of his boat while he was kayaking in the San Juan Islands two summers ago.

“Thank God he was wearing a life jacket and had a buddy with him,” says Ebel. “He is a strong swimmer, but the cold water just takes all the energy out of you. Over time, the cold water sapped his strength.” 

He tried his best to get back in his sea kayak, but he couldn’t get it righted. His life jacket kept his head above water and bought time for his friend to flag down a boat.  

“This turned out to be a story of gratitude. It could have been a different story if he hadn’t worn a life jacket,” says Ebel.

Recreating on (or in) Washington’s cold waters comes with risks, but there are things you can do to make sure you stay out of harm’s way.  

Why is cold water so dangerous?

Warm spring and early summer days in Western Washington are hard to beat — the skies are blue, the air is mild, the mountains are out and everything is in bloom. But this time of year, much of the water that fills our lakes and rivers comes from glacial and snowmelt from the mountains, making it extremely frigid.  

“That transition period between April, May and June, when the waters are still very cold, is when we see a large portion of our water-related deaths in Washington State,” says Ebel.

Here are some of the reasons why:  

Cold shock  

Even if the air is warm, water temperatures this time of year remain low enough to trigger cold shock, which causes a spike in blood pressure and involuntary gasping — you’ve probably experienced a sudden inhale if you’ve ever jumped into cold water or even turned on a freezing shower.  

Most people lose control of their breathing in water temperatures between 50 and 60 degrees. This isn’t necessarily dangerous if your head is above water, which using a life jacket will ensure. But if your head is submerged, those gasps can fill the lungs with water and can lead to drowning.

Physical incapacitation  

The body also loses heat up to 25 times faster in cold water than in cold air. Because the body is losing so much heat, arms and legs will start to weaken, making it hard for even the strongest swimmers to move their limbs. And if you’re in the ocean or a river with a current or rough water, swimming to shore will be challenging or impossible.  

“Most people drown quietly with no struggle,” says Ebel. “They’re just there, and then you look, and they’re not.”

Hypothermia 

Finally, because your body loses so much heat, you could experience hypothermia, which starts when your core body temperature drops below 95 degrees. As hypothermia sets in, your cognitive abilities become impaired, making it even harder for you to get to safety.  

How to stay safe in cold water

These dangers don’t mean that you have to stay out of cold water or wait until late summer to go for a dip. But there are some measures you should always take to stay safe.  

Wear a life jacket

Ebel’s number one tip is to wear a life jacket, whether you’re on a boat, paddling a kayak, floating on an inner tube or even cold plunging when you can’t touch the bottom.  

“It keeps your head above the water, so when the involuntary gasp reflex happens, you get air from the top,” says Ebel. “The second thing it does is buy you time.”

If you have a life jacket on, you will still be cold, but you will be able to breathe until someone can come rescue you or help you get to shore.  

Learn how to swim

If you’re an adult who doesn’t know how to swim, you’re not alone. But it’s never too late to learn.  

“Swimming is a powerful prevention against drowning, but more importantly, it’s awesome,” says Ebel. “The beauty of Washington is yours to claim when you know how to swim.”

Seattle’s adult swim programs include gender-specific classes and instruction in different languages.  

Don’t combine alcohol and swimming or boating

While a cold beer or hard seltzer might beckon on a hot day, leave the cooler at home.  

“When you’re on the water, alcohol and water don’t mix,” says Ebel.

According to Ebel, almost 90% of water-related injuries and drownings in Washington involve alcohol.  

Instead, stick to water and NA beverages, which come with the added bonus of keeping you hydrated in the sun.

Cold plunge safely

Cold plunge has become all the rage among the wellness-obsessed. There is data showing it can decrease short-term stress and inflammation, but the evidence is still limited for the many claims about longer-term physical and mental health benefits. 

While many specialized tubs and pools are now on the market, if you’re tempted to do it the old-fashioned way and jump in a lake, river or ocean, do it safely, especially when starting out.  

Make sure you can plunge without submerging your head — jumping into a cold body of water from a dock, boat or rock is not a good idea. Instead, walk slowly into the water from the shore so your body can adjust, and you can gauge how deep the water is. Your body can acclimate and reduce its cold shock response, which is why experienced cold-water plungers and swimmers can stay in freezing water without hyperventilating — but that takes time.  

Finally, if you have any heart conditions, talk to your doctor before trying a cold plunge. The adrenaline and blood pressure spike triggered by sudden immersion in cold water can be dangerous for people with heart disease or heart rhythm disorders.  

Swim somewhere with lifeguards

Seattle has many public beaches staffed with lifeguards and free life jackets to borrow for people who are not strong swimmers.

“Lifeguards significantly reduce the risk of drowning,” says Ebel.

If you see someone struggling in the water without a lifeguard around, don’t jump in and risk your own safety. Instead, throw them something that floats so that they can hang on while help comes.  

Enjoy the water, but stay safe

Washingtonians are lucky to have access to such beautiful lakes, rivers and sounds, but it’s important not to underestimate them.  

“The water can be really a brutal shock,” says Ebel.

You might not think you need a life jacket when you go on the water, but it could be the difference between a cold surprise and a much more dangerous situation, especially in the early summer when the waters run cold.