The status of lakes containing blue-green algae blooms in East Jefferson County remained unchanged after the latest test results were received Friday, with all lakes open for recreation.
Anderson Lake, which is near Chimacum, remains open to fishing and other recreation, though it is posted with a “caution” sign because of a light bloom of algae species known to sometimes produce such toxins as anatoxin-a, a fast-acting nerve poison that can be fatal, and microcystin, which can damage the liver after longtime ingestion.
Anderson Lake was reopened Aug. 27 after having been closed since June 10 because of high levels of anatoxin-a, which can cause convulsions and death by respiratory paralysis.
Anderson Lake State Park, which is around the lake, has never been closed to recreation.
Lake samples are taken each Monday for testing by King County Environmental Labs, and results are received in Jefferson County each Friday.
A trace of toxin was found in the Anderson Lake sample, said Mike Dawson, Jefferson County environmental health specialist, but the amount remained below recreational guidelines.
Warning sign at Gibbs
Gibbs Lake south of Port Townsend is open for recreation but with a “warning” sign posted because of a heavy bloom, Dawson said.
Lake Leland north of Quilcene is posted with a caution sign because it contains algae of a type that can produce toxins. Otherwise, it’s “in pretty good shape,” Dawson said.
A slight bloom is visible, and a trace of microcystin was found in the latest test results.
Silent Lake on the Toandos Peninsula is posted with a “caution” sign because of algae in the lake.
Sandy Shore Lake south of Port Ludlow remains clear.
Conditions can change
Lake conditions can change rapidly, and lake status may have changed since the last sample was taken, health specialists said.
Regardless of the posted sign at a lake, if a green paint-like scum or bloom is visible, then users should follow the recommendations listed at the “warning” level.
The “warning” level means people should not swim in the lake or drink its water, that pets and livestock should be kept away from it, boaters should avoid scums and fish should be well-cleaned, with the guts discarded.
The “caution” recommendations are the same except swimming should be avoided only in areas of scum.
Blue-green algae growth itself is thought to be encouraged by warm, sunny weather when sufficient nutrients, such as phosphates, are present. But researchers don’t understand why some species of blue-green algae will begin to produce toxins, nor what fuels increases in the amount of toxins.
Shallow, aging lakes are more likely to become overgrown with algae and contain toxins.
Clallam County lakes, most of which are deep and relatively free of algae, are not tested for toxins.
To report algae blooms in Clallam County, phone 360-417-2258.
Information about Jefferson County lake quality is posted at http://tinyurl.com/6z64ofy.
To report blooms in Jefferson County, phone 360-385-9444.
________
Managing Editor/News Leah Leach can be reached at 360-417-3531 or leah.leach@peninsuladailynews.com.
