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5 Ways To Tell If The Water Isn’t Safe For Swimming
Swimming in contaminated water can cause illness or even death in severe cases. Here is how you can tell if your favorite swimming hole is safe or not.
Editor’s Note: If you believe you, your children, or your pets have been exposed to toxins while swimming, seek medical attention immediately.
This summer, health officials are warning water lovers to be extra cautious of lakes, rivers, and oceans that are not safe for swimming in because of toxic algae or human waste. Toxic algae blooms are growing on lakes and beaches that can make people sick, poison children, and even kill pets. While algae usually aren’t harmful and can actually benefit marine ecosystems, they can bloom rapidly under certain conditions, which endangers wildlife and puts people who swim in the contaminated water at risk.
According to the Centers for Disease Control and Prevention, harmful algae blooms caused more than 300 emergency room visits between 2017 and 2019. Algal blooms may produce toxins and harmful gasses that can cause breathing problems, stomach pain, diarrhea, vomiting, coughing, rashes, and/or wheezing. Younger children and pets are typically most at risk for severe illness because they need less exposure to the algae to become sick.
Of course, it’s not just algae that can make swimmers sick. Swimmers trying to beat the summer heat in untreated water or bodies of water located near farms or sewage pipes could fall ill after accidentally ingesting water contaminated by sewage. While relatively rare, there are also unfortunately new horror stories every year about people or pets who died suddenly after becoming infected by brain-eating amoebas that thrive in warm water.
That said, this doesn’t mean you’re stuck on dry land all summer. It just means you need to use extra caution when deciding if it’s safe to swim at your local lake, river, or beach. Look out for these five signs that will tell you if the water isn’t safe for swimming, and if you have any doubt, don’t go in.
1.) The water looks funky.
If the water looks funky or weird, it probably is. Since algae can come in many different colors, you may be able to spot a dangerous bloom by looking for areas where it seems like paint could have been spilled in the water. Suspicious foam, scum, globs, or streaks on the surface of the water are also signs that algae may have bloomed and you shouldn’t go in. You could notice visible green scum in the water, which may look gross enough to make you rethink your swimming plans anyway.
2.) The water smells bad.
According to a California Water Guide, dangerous algae blooms emit a distinctive, often fishy smell that has been compared to septic, gasoline, and rotten eggs. The human nose is especially sensitive to a gas called hydrogen sulfide, which smells like rotten eggs and is released during decomposition. Exposure to this gas can lead to irritation of the eyes and respiratory system. In severe cases or through prolonged exposure, it can cause apnea, coma, convulsions, dizziness, headache, weakness, irritability, insomnia, and stomach upset.
The key takeaway: If the water smells bad, don’t swim in it.
3.) There are pipes draining into the water or you see clear signs of surface runoff.
Aside from algae, water might smell bad if it has been contaminated by sewage. Look out for pipes or signs of clear surface runoff that could be washing sewage or human and animal waste into swimming areas. Sometimes, sewage pipes drain into bodies of water. This is a problem because stomach bugs like norovirus and rotavirus are shed in human stool and can spread in contaminated water.
In other cases, heavy rainfall increases the risk that sewage spills over before it is properly treated, or that farm animal manure ends up in bodies of water because of surface runoff. If you think the water has been contaminated with sewage, make sure to contact the appropriate authorities so they can investigate and fix it if this is the case.
4.) There are dead animals or fish washing up on shore or in the water.
Unfortunately, it is part of the circle of life that fish and animals pass away. Finding a single fish or animal once in a while might not necessarily be abnormal. But if you are seeing lots of dead fish or animals floating in the water or washing up on shore, there is probably something wrong.
5.) Signs tell you not to go in.
If your local health department knows of an issue, they will likely put out signs warning against swimming in the water. If you see any warning signs, make sure to listen to them and avoid going in. Even if the signs are old or you haven’t heard about any problems elsewhere, they may be there to protect you from germs or toxins that make it unsafe to swim.
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