Volunteers for the Oregon Health Authority have put up warning signs in Willamette, Sellwood, Waterfront, and East Bank Esplanade parks. These signs caution river users against drinking or cooking with the water due to blue-green algae bloom scum that can produce harmful toxins.

(Adrianna Rodriguez)

More than a week after the discovery of toxic blue-green algae in the Willamette River, users are getting frustrated with the fact that they still have to stay away from the water.

An advisory, expanded Friday by the Oregon Health Advisory Board, pertains to the waters from Ross Island in Portland to the south end of Sauvie Island.

"It's not timely," said Rick McLaughlin, coach of the Golden Dragons paddling team.

The Golden Dragons is a team of senior citizens, 50 and older, who compete in various races paddling their colorful dragon boats. Normally, for three days a week, the team meets at the Little River Café at Southeast Water Avenue and Clay Street and practices for an hour on the river.

This week, the Dragons have not seen a single practice. McLaughlin said the team especially needed practice for a race on Sunday called Row for the Cure, an event to raise funds for breast cancer screening, support and research. A message on their website notifies members that there will be no paddling until further notice due to the bloom.

David Farrer, toxicologist with the Oregon Health Authority, said swallowing water containing the toxins produces symptoms similar to a flu such as numbness, tingling, dizziness, weakness, diarrhea, nausea, cramps and fainting. The OHA website also said inhalation of water droplets can lead to breathing problems, sneezing, coughing or a runny nose, while skin contact can cause skin irritation. Symptoms may appear in less than 24 hours.

Children and pets are at a greater risk due to the probability of ingesting higher doses of the toxins. However, dogs in particular like the taste of blue-green algae, said Farrer. They can quickly experience the symptoms and even die within the hour.

"An increased dose can lead to paralysis," said Farrer. "This paralyzes the diaphragm, which affects your breathing." Once you realize what's going on, it's usually too late.

Severe dehydration as a result of other symptoms, such as vomiting and diarrhea, can also lead to death.

There is no antidote if exposed to the toxins. The best way to deal with exposure is to treat the symptoms and let them pass through one's system.

Shawna Harch, spokeswoman at DoveLewis Emergency Animal Hospital, said the hospital saw two patients that were exposed to the toxins. Both were dogs and neither died.

"Mostly based on interviews that our veterinarians have done, most of the time it's when the water is actually ingested," said Harch.

Harch said the hospital advises that pets be washed with clean water immediately after exposure.

Signs have been placed by the OHA in parks such as Willamette, Sellwood, Waterfront, and East Bank Espanade advising the public to keep their children and pets away from the water. However, many of the signs put up by OHA volunteers have been torn down. The OHA is aware of this fact.

"It is unusual for sure," said Farrer of the algae's appearance. He said the OHA has never seen a bloom in the Willamette River since they started monitoring in 2005.

Peter Edwards, race director for the event Sunday, said he has been coaching on the Willamette for 25 years and has never heard of a bloom of blue-green algae on the river.

But he added that the river has been "behaving more like a lake or a reservoir right now, so it doesn't surprise me that we got it," said Edwards.

Conditions for algae growth were ideal. Although constantly moving, the Willamette's current was slow enough to allow the bloom to occur. Other contributing factors also include higher temperatures and lower water levels.

Travis Williams, executive director with Willamette Riverkeeper, said nutrients also played a factor in the bloom. Although a natural occurrence, this bloom could also be caused by excess nitrogen and phosphorus, nutrients that feed the toxic algae.

"You can't see as much algae of significant degree," said Williams. "Even if you don't see it on the surface, it might still run 10 to 12 feet deep."

He said the blue-green algae blooms are a part of the natural river world. Williams expects the algae should die off with cooler temperatures and rain.

However, Farrer said temperatures are a key factor in the algae's future. There is a chance that the coming rain could result in another flare of sun and warmer temperatures follow.

"The rain can cause a runoff of nutrients from land," said Farrer. "With the new nutrients in the water and if it turns hot again, then the algae can use these nutrients and flare up into a bigger bloom."

Golden Dragons coach McLaughlin hopes this isn't the case.

"I'm hoping that the rain coming in Wednesday will raise the water level and clear it out," said McLaughlin.

Edwards said race coordinators will decide by noon on Friday if the event will proceed as scheduled.

-- Adrianna Rodriguez