A cyanobacterial bloom has been detected in Half Moon Lake, stirring concern across Sherwood Park and its lakeside communities.

Locals have reported that the blue green algae are especially visible in warmer weather, turning the lake’s surface into swirling streaks of green, blue, or even brown patches.

This latest bloom has prompted an official lake water advisory, warning both residents and visitors to exercise caution.

The advisory specifically urges everyone to avoid swimming or wading in any areas where the bloom appears, emphasizing that visible algae can be deceptive and hazardous on the skin.

Contact with cyanobacterial blooms can cause a rash, sore throat, nausea, and other uncomfortable symptoms that often strike within hours.

According to recent reports, pets remain especially vulnerable. Exposure to toxins in the water can be fatal for dogs and other animals, making it crucial to keep them well away from the shore.

The advisory also reinforces that boiling lake water does not eliminate the toxins produced by cyanobacteria.

Residents are urged to never drink or cook with untreated lake water, even if the algae are not visible in a specific area.

Many in Sherwood Park recall past summers when the excitement of weekends at Half Moon Lake was dampened by visible blooms and urgent public health warnings.

The sight of what looks like grass clippings, fuzzy mats, or paint on the water’s surface is also accompanied by an unmistakable musty odor—prompting concern and, at times, frustration among local families who depend on the lake for recreation.

Those fishing nearby are reminded that toxins may accumulate in fish organs, so only fillets are considered safer to eat, and fish trimmings should never be fed to pets.

Shifting winds and changing weather mean that the cyanobacterial bloom can move rapidly across Half Moon Lake, making the situation unpredictable.

Crowds may still enjoy parts of the lake where the bloom is not present, but caution remains the watchword for the entire community.

Officials remind all visitors to stay updated on lake water advisory developments as conditions evolve.