Welcome to the freshwater algae site

The purpose of this site is to provide toxin data related to cyanobacteria blooms in Washington lakes, ponds and streams. Washington State Department of Ecology (Ecology) uses this site to share the data from their ongoing freshwater algae monitoring program.

Cyanobacteria (or blue-green algae) can produce toxins at levels that are harmful to humans, pets, domestic animals, and wildlife. There is no way to detect toxins in an algae bloom except through laboratory analysis. This website provides access to Ecology's results.

Find your lake

Find your lake

Use our database to locate a lake and find out the most recent testing.
Or find your lake >

See lakes with algae bloom

Find your lake

Examples of local lakes experiencing algae blooms.
View our gallery and descriptions.

Report a bloom

Find your lake

If you think that your lake has an algae bloom and you want to have the algae identified: Report a bloom.

Health risks

Find your lake

Learn about the potential health risks to people and pets exposed to algae blooms through swimming or consuming the water.

Current lakes with values above guidelines

LocationLast Sample Date
Cranberry Lake, Island08/26/2015
Ohop Lake, Pierce08/26/2015
Spanaway Lake, Pierce08/26/2015
Bay Lake, Pierce08/24/2015
Wapato Lake, Pierce08/24/2015
Lake Jeane, King08/23/2015
Lake Cassidy, Snohomish08/18/2015
Rufus Woods Lake, Douglas08/12/2015

Links to external sites do not constitute endorsements by King County. By visiting this and other King County web pages, you expressly agree to be bound by terms and conditions of the site. For questions on the Freshwater Algae Program please contact . For questions on the content or functionality of the site please contact .

© 2012 King County

King County Washington State Department of Ecology Washington State Dept. of Health