PORT TOWNSEND — Fall blooms of cyanobacteria, also known as blue-green algae, have resulted in rising toxin levels at two Jefferson County lakes, according to Jefferson County Community Health.
A water sample from Lake Leland collected on Monday was found to have 14 micrograms of microcystin per liter, above the Washington state guidance level of 8, reported Michael Dawson, water quality manager, Friday.
Microcystin is a liver toxin that can harm people and pets. Warning signs have been posted by Jefferson County Public Health at the boat ramp and fishing pier.
Anderson Lake continues to have a toxic bloom, although the toxins have changed since the beginning of the year, Dawson said.
The microcystin level at Anderson Lake reached 2,776 micrograms on Oct. 4. The lake has been posted with Danger — Lake Closed signs since May, when high levels of the potent nerve toxin anatoxin-a, which acts very quickly and can cause death, were measured.
Blooms of cyanobacteria were observed in Gibbs Lake and Crocker Lake last summer but toxin levels have declined and both lakes have been free of visible blooms in recent weeks, Dawson said.
Informational signs about toxic algae are posted at both lakes.
Lake conditions can change rapidly and lake status can change between samples, he warned.
The county health department urges recreationists to avoid contact with heavy blooms or scums.
Anyone who sees a bloom in a Jefferson County lake is urged to report it at 360-385-9444.
Blooms have not been seen in Clallam County lakes.
To check the status of Jefferson County lakes and learn more about toxic cyanobacteria monitoring, see www.jeffersoncounty publichealth.org/723/Lake- Status.
For fishing seasons and regulations see the state Department of Fish and Wildlife website at www.wdfw.wa.gov/fishing.
