Adam Spencer, The Triplicate

Toxic blue-green algal blooms have reappeared in the Lower Klamath River, prompting officials from Del Norte County, the Yurok Tribe and the state's water quality department to warn the public to avoid contact with algae this summer.

At Klamath River access points from Iron Gate Dam to the estuary, public health advisories were posted this week warning against human and animal contact with the water. Contact with blue-green algae blooms can cause eye irritation, allergic skin rash, mouth ulcers, vomiting, diarrhea and cold and flu-like symptoms.

"These conditions in the Klamath River and reservoirs today are very concerning. Blue-green algae can pose health risks, particularly to children and pets," said MattSt. John, Executive Officer of the North Coast Regional Water Quality Control Board.

"We urge people and their pets to avoid contact with water in locations with blooms, and particularly avoid swallowing or inhaling of water spray in an algal bloom area."

The toxic blooms appear as green, blue-green, white or brown scum, foam or mats floating on the water. Since it can be difficult to determine the difference between toxic blue-green algae and harmless green algae, fresh water users are urged to avoid all algal blooms.

Although there is a large amount of harmless algae present in the Smith River this year due to low flows, Forest Service officials said that blue-green algae is not yet an issue in the Smith River, where coastal influences keep water temps down.

Toxic blue-green algae (cyanobacteria) is actually a bit of a misnomer since it is not related to any other type of algae, but it is a type of aquatic bacteria capable of photosynthesis.

The bacteria can produce a liver toxin that - in rare situations - has caused liver failure, nerve damage and death where large amounts of contaminated water were directly ingested, according to the Water Quality Control Board.

Current status of cyanobacteria blooms can be found at the website of the Klamath Basin Monitoring Program ( by clicking the "Blue-Green Algae Map."

Questions about blue-green algae can be directed to the Del Norte County Public Health Branch at464-3191 ext. 2824, the Del Norte County Environmental Health Department at 465-0426 or the Yurok Tribe Environmental Program at 482-1822 ext. 1013.

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