How to avoid 5 surprising risks of swimming in Canadian lakes

woman-walking-into-lake Photo by Chris G. Walker/Shutterstock

There’s nothing quite like jumping into the lake on a hot summer day. If you’ve grown up in Canada or even if you’ve just spent a summer or two in our backyard, it’s likely you’ve taken advantage of one of Canada’s many picturesque lakes. From sea to sea, our country is home to more lake area than anywhere else in the world with freshwater covering almost 9% of our total land mass. Whether you’re doing the breaststroke or the doggy paddle, in a wet suit or sans bikini, training for a triathlon or just wading in the sand, lake swimming can be a calming and chlorine-free way to enjoy yourself. But amidst the pleasant waves and peaceful loon calls, a number of surprising health risks that smart swimmers should try to avoid.

Lake pathogens

There was a good reason why Mom always told you to swim with your mouth closed. Some lake water can be home to thousands of microscopic parasites and bacteria that can potentially cause illness. E. coli and Gardiasis are two that are commonly associated with lake water, and they can produce flu-like symptoms such as diarrhea, stomach cramps, vomiting, and fever. Children and the elderly can be especially susceptible to complications associated with both. What’s the best way to avoid this danger lurking in the water? Although both are impossible to see with the naked eye, be wary of murky, dirty or stagnant water, which can harbour bacteria. Look for beach warnings (most public beaches are tested daily for E. coli levels), avoid consuming water while swimming, and always shower when your swim is done.


It’s Indiana Jones’s worst nightmare, and believe it or not, it’s also in our own backyard. But unlike Harrison Ford, if you encounter it, you might not have Shia Labeouf or a giant snake to come to your rescue. Surprisingly, quicksand exists all over Canada wherever there’s too much water in the sand or granular soil, making it common near rivers, lakes and marshes. If possible, avoid areas surrounding water that you suspect might be home to quicksand, and if you do get stuck, avoid struggling—it will only stir up the sand and increase the suction. Slowly pull yourself out by working to distribute your bodyweight horizontally and grabbing solid. And if possible, mark the area to prevent other hikers, swimmers, or cottagers from falling into the same trap you did.

Otter attacks

Often thought of as cute, cuddly, hand-holding creatures, these critters are stirring up lakes and changing opinions everywhere. An attack in a British Columbia lake left a woman with nine otter bites, putting her at risk of infection and leaving deep wounds on her arms, thigh and calves. Otters, like many other animals, are territorial, especially during spring pup season, so your best bet is to avoid the rivers they frequent and observe them from afar.

Zebra mussels

This lake menace is likely a bigger health risk to our aquatic ecosystem due to the fact they spread rapidly, consume large quantities of plankton, clog drain pipes and have few enemies to eliminate them, according to the Canadian Wildlife Federation. However, zebra mussels can also pose harm to swimmers’ feet because their shells are extremely sharp. Be wary of swimming in shallow, rocky water that you suspect may be home to the black and white mollusc, and avoid spreading them by removing them from your boat (paint scrapers work best) before entering a new waterway.

Rip currents

Also sometimes referred to as undertow, rip currents occur as a narrow and strong current of water that runs perpendicular to the beach and into the water. These currents of water are extremely powerful during large waves and can pull you far from shore. If you get caught in a rip current, swim sideways and parallel to the beach, don’t panic, and if possible, avoid swimming in close proximity to piers where rip currents commonly occur.

If you can conquer these five health risks, slather on the waterproof sunscreen and safely enjoy swimming in the many beautiful lakes Canada has to offer. Happy swimming!