American Lake algae bloom has disappeared, officials say

By Rachel Young, Northwest Guardian

Fort Lewis officials identified a toxic, blue-green, algae bloom in the south end of American Lake June 20.

The bloom, which has since disappeared, was identified by the Tacoma Pierce County Health Department as anabaena, a cyanobacteria that can produce neurotoxins.

Neurotoxins can cause muscle cramping, twitching and paralysis, according to Maj. Jennifer McDannald, chief of environmental health at Madigan Army Medical Center.

“But blue-green algae, if you come in contact with this, you’re going to notice things like tingling in your fingers and toes, dizziness or numbness of the lips in a human,” McDannald said. “It’s actually more of a threat to small animals or fish, waterfowl, than it is to humans.”

However, if a human does come into contact with it, through ingestion, inhalation or through skin contact, that person needs to seek medical care immediately. And if a pet comes in contact with the algae, seek veterinary care immediately, she said. The blooms are caused by a number of factors, like the amounts of nitrogen and phosphorous in the water, light, temperature and percentage of oxygen saturation, according to Joyce Chavez, water program manager for Fort Lewis Directorate of Public Works. The blooms generally die off on their own in a matter of weeks, but if conditions remain ideal, another may appear.

American Lake is particularly susceptible to toxic algae blooms because the sediment tends to be nitrogen and phosphorous rich.

This is not the first time a toxic bloom has appeared in American Lake, but they usually spring up in the winter, Chavez said.

“Summer is a little more rare than the winter time, but it’s usually shorter-lived,” she said. “Usually when they find these places, they try to post signs around the shoreline to let the public know.”

Users of American Lake are asked to be on the lookout for blooms. They look like pea soup, or green paint, in the water, Chavez said. To help reduce the risk of toxic algae blooms, residents can pick up after their pets regularly, reducing the amount of nitrogen in the environment. Also, when fertilizing, try not to have any runoff.

“Fertilizers have a lot of nitrogen and phosphorus,” Chavez said.

If you see what you think is a toxic algae bloom, stay away from it, keep children and pets out of the water, and call Tacoma Pierce County Health Department at 798-6470 or Chavez at 967-2837.