Lost Creek Lake likely won't get a clean bill of health until mid-November now that a stubborn blue-green algae bloom seems to have rejuvenated in recent days, authorities said.

Lost Creek Lake likely won't get a clean bill of health until mid-November now that a stubborn blue-green algae bloom seems to have rejuvenated in recent days, authorities said.

After appearing to be subsiding through much of last week, blooms of Anabeana flos-aque resurfaced over the weekend and led health officials to extend a no-water-contact advisory that has been in place since Sept. 16.

"It gave a false appearance that it was going away, but it resurfaced," said Eric Amerson, a park ranger for the U.S. Army Corps of Engineers, which manages the lake. "It's about as bad as I've seen it.

"It's pretty brutal," he said.

Corps officials had hoped Monday to begin the two-week waiting period to allow any toxins produced by the dying algae to dissipate naturally.

That waiting period, which follows Oregon Department of Human Services guidelines, would have allowed the health advisories to end Nov. 10 had the lake water looked good Monday.

But after a warm weekend, Amerson's view of the largest water body in Jackson County showed large clumps of the green-brown algae, he said.

The countdown "won't begin today and it won't be for the rest of the week," Amerson said Monday. "The algae looks thick out there. It's pretty ugly. "

The advisory includes a recommendation that anglers practice catch-and-release fishing until the advisory is lifted. The restrictions are not mandatory.

Swallowing or inhaling water droplets should be avoided, as well as skin contact with water by humans or animals. The toxins cannot be removed by boiling, filtering or treating water.

If people choose to eat fish from the reservoir, they should remove all fat, skin and organs before cooking since toxins are more likely to collect in these tissues, the advisory states.

Despite the warnings, a few anglers' boats have been seen at the lake daily this month, and the Corps has fielded telephone calls from an inquiring public, said Jim Buck, the Corps' project manager.

"There certainly is an awareness that the health advisory remains listed," Buck said.

This algae strain, which is actually a form of bacteria, releases neurotoxins that can cause everything from a skin rash and dizziness to rapid death, though documented reactions were extremely rare in Oregon.

It is most threatening to children and pets, and it congregates mostly in shallow, stagnant coves and along shorelines.

Algae outbreaks have plagued a number of Oregon reservoirs this decade. Advisories also remained in effect Friday at Wickiup Reservoir in Deschutes County, Willow Creek Reservoir in Morrow County and Devil's Lake in Lincoln County.

An advisory for Dexter Reservoir in Lane County was lifted Wednesday, health officials said.

Reach reporter Mark Freeman at 776-4470, or e-mail mfreeman@mailtribune.com.