Health advisories recently issued for Pine Lake and Pigeon Lake have warned lake users that blue-green algae blooms have been found in parts of those lakes, and to avoid contact and consumption of the affected waters.
But no such advisory has been issued for Sylvan Lake, said Deena Hinshaw of Alberta Health Services, describing the conditions needed for algae blooms to form in the lake.
“Lakes at higher risk are those that have high nutrient levels,” she said. “Where there are fertilizers going into the lake or animals or human waste going into the lake, and combined with the depth and warmth of the water, all of those things together bring up the risk.”
She added there’s a “whole series of things to happen for algae blooms to occur … you need to have the high nutrient levels, the warm enough temperatures for growth, and a storm followed by calm is the final piece of that.”
Graeme Strathdee, president of the Sylvan Lake Watershed Stewardship Society, said Sylvan Lake remains “well below the concentration that would trigger chronic algae blooms,” but admitted ongoing development around the lake was a concern.
“The concern is that, with a lot of increased development, it will dump stuff from the land into the lake,” he said.
Blue-green algae isn’t an imminent problem for Sylvan Lake, he added; rather, it depends on nutrient levels in the lake.
“You never know what the lake will do next,” he said. “It depends on the weather and the precipitation, and how much runoff there is, and a whole bunch of other things.”
The advisories issued for Pigeon Lake and Pine Lake strongly suggest that lake users avoid the parts of those lakes with the algae blooms due to the toxins in the water, because direct contact will likely cause symptoms such as skin irritation, runny nose and sore throat and eyes.
If ingested, lake users can experience flu-like symptoms such as headaches, diarrhea, weakness, vomiting, muscle and joint pain, abdominal cramps and — depending on how much of the toxic water is consumed — even liver damage that can result in death.
In addition, people are advised to keep pets and animal livestock away from the lake areas containing the blooms, and it is advised to limit whole fish or fish trimming consumption with fish fillets deemed safe to eat.