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caption: Marisa Burghdoff of Snohomish County tests an algae bloom at Lake Ketchum in the county's northwestern corner.
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Marisa Burghdoff of Snohomish County tests an algae bloom at Lake Ketchum in the county's northwestern corner.
Credit: Washington State Department of Ecology Photo

Lake gunk a 'local impact of climate change' in Washington state

If you’ve been to a lake or pond lately, you might have noticed a rust colored, oily layer on the water. It could be a toxic algae bloom. The state’s Department of Ecology says it’s testing samples from at least 20 lakes across Washington right now for the algae.

Here in King County, Hicklin Lake and Lake Marcel are closed to the public after water samples contained potentially harmful levels of cyanobacteria, better known as blue-green algae.

Colleen Keltz, a spokesperson with the Washington State Department of Ecology, says the warmer temperatures western Washington has experienced this spring and summer during the "heat dome" creates ideal conditions for the bacteria behind algae bloom to grow.

"We could say it's a local impact of climate change," Keltz said. "These blooms are starting sooner, and they're lasting longer."

Humans and animals can also fuel algae bloom growth.

"Maybe a lake is getting a lot more recreation around it, and maybe pet waste isn't being cleaned up," Keltz said. "Folks are using more fertilizers and pesticides that are running into the lake."

The state is currently monitoring six other bodies of water after their toxin data came back above state guidelines, according to the department of ecology's algae bloom monitoring program.

Swimming in a lake with toxic algae bloom can make humans sick and experience a range of symptoms like headaches, skin irritation, and vomiting. It can also be deadly to pets.

Keltz said the state collects data only on the water samples that have been sent to them, and that it's difficult to determine whether warmer temperatures are causing more cases of toxic algae bloom across Washington compared to years past, or the impact it's having on ecosystems in the long term.

For now, the Department of Ecology asks that people keep an eye out for algae bloom before they go for a dip in a lake. If you see a splash of blue-green or red with the texture of pea soup or oil on top of the lake, Keltz says to take a picture and report it to the Department of Ecology's website.