Lakes are a critical freshwater resource providing an array of recreational opportunities, valuable habitat for fish and wildlife, and tranquil beauty. Our geologic history has led this area to be rich in lakes with Snohomish County having over 400 lakes. While the majority are very small or located in the Cascade mountains, there are around 60 lakes located in the populated lowland areas.
Lakes experiencing toxic algae blooms are listed below and have been posted with WARNING signs. The WA State toxin testing program is closed for the winter, WARNING signs are posted when scum is present.
Updated 2/19/2021
BLACKMANS LAKE - intermittent blue-green algae blooms with green scum near the shoreline. Previous sample results show that Microcystin, a liver toxin, were detected at 22 ppb. This is above the WA state Recreational limits of 8 ppb. If you would like to sign up for alerts, please visit the City of Snohomish website and sign up for NewsFlash updates.
LAKE HOWARD - heavy blue-green algae bloom along the shoreline near the boat launch. Previous algae samples contained species known to produce liver toxins and neurotoxins.
LOST LAKE - heavy blue-green algae bloom at the south end of the lake. Previous algae samples contained species known to produce liver toxins.
LAKE SHOECRAFT- intermittent blue-green algae bloom along the shorelines. Previous algae samples contained species known to produce neurotoxins.