According to city of Maple Valley officials samples taken from the beach at Lake Wilderness Oct. 3 have measured very high for microcystin from blue-green toxic algae, which is known to cause liver damage.

Officials urge people and pets to say out of any visible scum. Following state guidelines, the Lake Wilderness Park shoreline will continue to be posted with warning signs to let the public know that toxins are present.

Lake Wilderness developed a toxic bloom the last week of August, however, samples through the month of September indicated the toxins had decreased to trace levels.

Every other week algae sampling will continue through Oct. 18 and updates will be posted on the city Web site, www.ci.maple-valley.wa.us.

The Center of Disease and Prevention issued a grant for a multicounty study to learn more about the blue-green toxic algae and what causes it to develop toxins. The species identified in Lake Wilderness is Anabaena flos-aquae and is know to thrive in lakes until winter when cold weather and rains decrease the population.

Algae blooms are usually caused by climate conditions and nutrient enrichment, in particular phosphorus, but officials hope to learn more about toxic blooms through the algae grant program.

The state Department of Ecology maintains a toxic algae data base where users can look at sampling results by individual lakes at https://fortress.wa.gov/ecy/toxicalgae/InternetDefault.aspx

For more information contact Sally Abella, science and technical support, King County Water and Land Resources Division at 206-296-8382 or sally.abella@kingcounty.gov.