Article Courtesy of Kristian Foden-Vencil|KUOW.ORG|September 17, 2014| Shared as Educational Material
State officials are testing water from a stretch of the Willamette River near downtown Portland. The tests come after a trail of scum appeared in the river between Ross Island and the Fremont Bridge.
The water is being checked to see what species of blue-green algae is involved. That’ll give health experts an idea of the level of toxins and whether the bloom might be harmful to people.
Rebecca Hillwig with the Oregon Health Authority says it’s unusual to have an algae bloom in such a large, relatively fast-flowing river.
Willwig explained, “It is the first time that I know of, and that most of the people I’ve talked to, know of there being a bloom in the Willamette specifically. We have I guess in the past had an advisory for the Tualatin River. But you know if you were to look at the Willamette in the area where the bloom has been identified, you know that’s a channel that is pretty calm.”
The state is warning people not to swim-in, or drink out of, the Willamette River.
Exposure to toxins from blue-green algae can produce symptoms of numbness, tingling and dizziness that can lead to difficulty breathing or heart problems. Public health officials say the toxins can’t be removed by boiling or treating the water with camping-style filters.
Test results are expected Wednesday or Thursday.
Wilsonville takes its drinking water out of the Willamette. Health officials say public drinking water systems can reduce algae toxins through proper filtration, but toxins can’t be removed by boiling or treating the water with camping-style filters.
Hillwig says our warm weather this summer may be partly to blame for the bloom.
“The environmental triggers just happen to be right. The water is lower, it’s been very hot this summer, so the water is warmer than normal. It’s calm in that area and they are obviously getting the nutrients they need, which is phosphorous and nitrogen.” she said.
This was first reported for OPB.