PORT TOWNSEND — The amount of potentially toxic blue-green algae in three Jefferson County lakes remains dangerously high on the eve of a seasonal reduction in the frequency of water testing.
Anderson, Gibbs and Leland lakes remain too clogged with algae to recommend any recreational use, said Neil Harrington, Jefferson County’s water quality program manager, after receiving last week’s results of samples of lake water.
“There are still no significant changes,” Harrington said Friday. “We’re still recommending the same warnings that we’ve had for three weeks.”
Red warning signs remain posted at all three lakes.
That means that the lake is closed to recreational use, including fishing and swimming, because of the potential for ingesting liver toxins or neurotoxins from the algae.
No one should drink the water; boiling it or treating it will not destroy the toxin.
Both Gibbs Lake in Chimacum and Lake Leland, north of Quilcene and south of U.S. Highway 101, were found to contain more than 100,000 cells of algae per milliliter, while Anderson was up to 1.5 million cells per milliliter.
Blue-green algae is a common fresh-water scum that can, at times — for reasons researchers don’t understand — begin producing toxins that can damage human and animal livers or neurological systems.
Harrington surmised that continued warm weather may be the reason that algae blooms are so robust.
“It’s been pretty nice, not a lot of wind and plenty of sun,” he said. “I’m hoping that with cooler weather, the algae will die down.”
Although Anderson Lake is closed, the park around it — Anderson Lake State Park, near Port Hadlock — remains open to non-lake orientated recreation such as hiking, horseback riding and biking until the seasonal closure Nov. 1.
Tarboo, Crocker, Teal and Sandy Shores lakes have all tested as being clear of algae.
Water sampling
Monday will mark the last weekly water sampling of the season, Harrington said.
Instead, tests will be conducted monthly until next spring.
One reason for the cutback is the reduction in use commonly seen in the fall.
“In the summer, we get a lot of recreation use, and keep better track of it,” Harrington said. “Come October, there’s a lot less recreational use.”
Another reason is funding.
Although the county health department has sampled lake water since 2006, it received a $42,000 grant from the state Department of Ecology in October 2008 — augmented by some county funds — to fund data collection for a year-long study of why algae is growing in some lakes.
“The grant started in October, but we spent most of the winter going back and forth with Ecology to get the quality assurance and plan worked out,” Harrington said.
“We finally had that approved in April. We started sampling under the grant in April.”
The grant will be sufficient to fund the sampling for the full year with winter sampling cut to a monthly frequency.
Study results next spring
Harrington expects to announce results of the algae study in April or May.
“We’re looking at what’s driving it, to find what are the causative factors of the algae blooms,” Harrington said.
It was in 2006 that public health officials discovered the threat that blue-green algae represents.
Two dogs died after drinking water from Anderson Lake. The lake was closed to recreation for several months that year, and for increasingly long periods during the warmer months each subsequent year.
This year, the popular trout-fishing lake was closed earlier than ever before — on April 24, just before the opening of the season.
The Ecology-funded study is examining both the amount of algae in the lakes and the toxicity, as well as looking at potential causes of the blooms.
Warnings at lakes are posted in response to the amount of algae in the water, partially because it takes longer to get toxicity testing results than cell number counts.
“We know that certain cell numbers can lead to a certain toxicity, and it’s hard to know if any bloom will be toxic at any given time,” Harrington said.
The cause of algae blooms is considered to be high amounts of phosphorus.
Anderson Lake contains more phosphorus than Lake Leland, Leland has more than Gibbs Lake, and Gibbs’ phosphorus content is higher than Sandy Shore, Harrington has said.
The mystery is the origin of the phosphorus.
Phosphorus is an ingredient in fertilizers, and can be in septic-system effluent, but Anderson Lake, for instance, is within a state park where no fertilizing is done and where the septic system is sound, Harrington has said.
Phosphorus can get into lakes through the atmosphere or runoff, or it could be historical. Harrington has said he is checking records to see if a former use at Anderson Lake could have contributed to the present bloom.
Whatever the source, phosphorus tends to concentrate in lakes with no outlet, such as Anderson Lake. By comparison, Sandy Shore Lake — which is clear of algae — is the headwaters of Thorndyke Creek.
Jefferson County Public Health maintains an updated database of lake monitoring information at tinyurl.com/jeffcolakes. The department can be reached at 360-385-9400.
Lake samples are not tested in Clallam County, where health officers visually monitor lakes for signs of algae bloom. No cautions or warnings have been issued in Clallam County.
Algae blooms in Clallam County lakes should be reported to Clallam County Department of Health and Human Services environmental health division at 360-417-2258.
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Managing Editor/News Leah Leach can be reached at 360-417-3531 or leah.leach@peninsuladailynews.com.
