It’s now safe to swim and boat in the North Portland area of the Willamette River, according to Oregon health officials.
On Monday, the Oregon Health Authority lifted its recreational use advisory for Willamette Cove, which has been in place since July because of cyanobacteria blooms. An advisory is still in place farther south for the Ross Island Lagoon, as well as six other bodies of water across the state.
Cyanobacteria, also known as blue-green algae, thrive in warm, slow-moving water that are rich in nutrients, such as fertilizer or sewage. Cyanobacteria can be harmful to people and pets when inhaled or absorbed through the skin.
Oregon Health Authority officials on Monday said cyanobacteria blooms can develop and disappear in any body of water at any time, and only a fraction of the state’s waters are monitored for blooms and toxins.
Though cyanobacteria isn’t always visible, officials recommend people avoid water that is scummy or green, or if there are brownish-red mats or bright green clumps suspended in the water. If you see those signs, avoid activities that could cause you to swallow water or inhale droplets, like swimming or high-speed boating, and keep pets out of the area.
A tug sails through a harmful algae bloom in downtown Portland. Aug. 16, 2023
Courtesy Willie Levenson/Human Access Project
