A suspected blue-green algae bloom at Alice Lake has prompted Vancouver Coastal Health to label the popular destination not suitable for swimming.
The health authority posted the water quality advisory to its website this week, saying the water isn’t safe to swim.
The site typically posts E. coli levels for popular swim spots in Metro Vancouver and the Sea to Sky region. The only other beach closed for swimming is Trout Lake in Vancouver due to elevated E. coli levels.
Blue-green algae is a commonly used name for cyanobacteria. The single-cell organisms tend to grow in water that’s shallow and still, including ponds and freshwater lakes.
The BC government says on its website that large blooms of cyanobacteria produce toxins that can be harmful to humans, pets, and livestock.
“When the amount of cyanobacteria in a water body increases, a dense mass called a bloom will form. Cyanobacteria blooms are natural. However, some human activities (such as agriculture or a poorly functioning septic system) can make blooms more likely,” the BC government’s site says.
Blooms often cause lake water to smell bad and look different.
Swimming in water with a cyanobacterial bloom could cause skin rashes and irritation around the ears and eyes. These symptoms are typically visible shortly after contact with the water, and authorities recommend rinsing with clean water immediately after exposure.
Symptoms from drinking water with cyanobacterial toxins include headaches, nausea, fever, sore throat, dizziness, stomach cramps, diarrhea, abdominal pain, vomiting, muscle aches, and ulcers or blisters in and around the mouth.
Anyone experiencing symptoms from suspected contact with cyanobacterial toxins is advised to seek medical attention.