News Flash

City of Snohomish - NewsFlash

Posted on: December 9, 2020

Toxic Bloom of Blue-Green Algae

Blue-Green Algae

Blackmans Lake is still experiencing a blue-green algae bloom with scum accumulating along the shoreline. The algae scum looks like green paint floating on the surface of the water.


The State sampling program for toxins has closed for the winter so no samples will be taken.


Please assume that toxins are present where there is scum in the absence of testing.. 


WARNING signs were posted at the public access sites at the boat launch and Hill Park. The signs provide guidance for lake recreation (see sign below). It is especially important to avoid areas of algae scum because this is where the toxin levels are the highest.


The WARNING signs advise the following:

  • Do not swim in the lake
  • Do not drink lake water
  • Keep pets away from the lake
  • Clean fish well and discard guts
  • Avoid areas of scum when boating


Toxic algae can cause serious illness in humans who drink or play in affected waters. Pets that drink the water are at particular risk. If you or your pet are exposed to a blue-green algae bloom and have unexplained sickness or signs of poisoning, call your health care provider or veterinarian. Find out more about toxic algae by visiting www.nwtoxicalgae.org.

Facebook Twitter Email

Other News in City of Snohomish - NewsFlash

Meeting Gavel

Upcoming City Council Workshop

Posted on: January 22, 2021
MPD Image

It’s Not Too Late to Participate

Posted on: January 21, 2021
Snohomish Community regarding COVID-19

COVID-19 Vaccine FAQ

Posted on: January 11, 2021
New Development App

New Development Application Received

Posted on: December 18, 2020
Council Audio

City Council Meeting Audio

Posted on: December 17, 2020