Low Willamette River flow, high heat driving large toxic algae bloom, OHA says

PORTLAND, Ore. (KOIN) – The Oregon Health Authority is expanding its advisory for a harmful algae bloom on the Willamette River.

Officials are warning about a cyanobacteria bloom. Now they are testing the water to see if they can lift the recreational safety advisory. The OHA said this is the first time in about ten years they have had an advisory this size. It now stretches from Ross Island Lagoon and Bridge all the way to Wapato Bridge and Kelley Point Park near Sauvie Island.

If exposed to cyanotoxins, the OHA warns you could feel a range of symptoms from nausea and stomach cramping to dizziness or shortness of breath. They said exposed dogs could even die.

While the OHA has seen advisories cover large parts of the river before, they want to make sure people still take them seriously.

“We suggest that people do not wade or swim in the river or do other things that could cause them to ingest water,” Linda Novitski with the Oregon Health Authority said. “We recommend that people do not do power boating. Where there’s spray, they can go into their faces or they could be inhaling water. This includes things like, water skiing where you might be, getting a lot of water into your face.”

Novitski said if people want to get out on the river still, they should try canoeing or kayaking. The point is to avoid getting water in your face or mouth, because that is when you have the highest chance to expose yourself to toxins.

Desiree Tullos is a Water Resources Engineer at Oregon State University. She said the low water year we are having is partially to blame for the large bloom.

“So flows in the river are lower than they have been other than median flows,” she said. “And what occurs on a regular basis. And the river’s hot. And so those are two conditions in particular that really drive the stagnant hot conditions that blooms thrive in.”

Before anything changes OHA officials need to know the toxin levels of the water. Right now they are noting there is a bloom, they have samples, but they need the results.

“When we receive the cyanotoxin information, if the values are above OHA’s recreational use values that are for human health, then we continue with the advisory,” Novitski said. “If they fall below our recreational use values, then we would likely lift the advisory.”

Until the OHA gets those test results, Novitski said people just have to wait it out. But she said they should know by next week.

Novitski encourages people to report blooms or human or animal illnesses to the OHA here.