Splashing around: Checking up on water quality at the beach

June 20, 2023


Swim suits – check! Sand toys – check! Sunscreen – check! But don’t forget to check the water quality at your favourite beach to make sure it’s safe to enjoy the water.

Your municipality or local water management authority provides information on beach water quality so that you can make informed decisions before heading to the beach. Health Canada also works with provinces and territories to develop guidelines on testing and monitoring. These tell the experts what to look for in the water to get a sense of whether or not it’s safe to swim.

Teresa Brooks, a Senior Evaluator at Health Canada, plays a key role in the development of these guidelines. “The guidelines provide information to help determine how to manage recreational waters. There is flexibility in how they can be used since every recreational water area is different and so the best approach can vary between different sites,” she explains.

In fact, the guidelines propose checking for what the experts call “fecal indicators”, a group of germs that are present when the water is contaminated. “Germs that can cause disease are called pathogens. Testing for pathogens is difficult, time consuming and technical. It’s just not feasible,” explains Teresa. As such, those responsible for the beaches will generally test for indicator bacteria like E. coli or enterococci. These then indicate whether there is possible contamination from other more dangerous germs.

“Some of the risks when swimming in natural waters like lakes or rivers are linked to pathogens that cause gastrointestinal illness, and eye, ear and skin infections,” says Teresa. Researchers have determined what levels of indicator bacteria show that people have a greater chance of getting sick, and when they shouldn’t be playing in the water.

“Each beach should have a water management plan to determine where the contamination could be coming from, what types of contaminants may be present, and when there could be a concern – after a heavy rainfall for example,” says Teresa. This allows beach managers to get a sense of the impacts on water quality, even before testing.

Don’t forget that there are also risks to playing in the sand. With water washing up on shore and animals living in the area, pathogens can be present there as well. “It’s hard to monitor beach sand quality, because it varies a lot over the length of the beach,” says Teresa. To protect yourself, it’s important to always wash your hands after playing in the sand.

Recreational water in a changing climate

Climate change is also having an impact on the safety of water at the beach. In fact, an increase in heavy rainfall has the potential to wash more pathogens into the water. It could even cause combined sewer overflows to impact your favourite swimming hole more often. Those responsible for testing the water need to have a good understanding of the potential sources of contamination.

In addition, warmer waters can have an impact on the growth of bacteria and algae, particularly the cyanobacteria, better known as blue-green algae. You may have seen it around your local beach, as it’s become more and more present over the last few years.

Cyanobacteria blooms can contain dangerous toxins and be harmful to your health. Some places will have them only periodically, when the conditions are right, while others will see them every year. If they are present, stay out of the water.

Canadians are lucky to have plenty of lakes and rivers with beautiful beaches for summertime fun. Splash around safely!

Additional Resources

Recreational water quality and health