A New Approach Didn’t Curb the Spread of a Toxic Algae Bloom Down the Willamette River

Toxic algae blooms in the center of the Willamette River have become one of Portland’s unwanted summer traditions. The blooms erupt in Ross Island Lagoon, a stagnant inlet left by gravel mining; by now, Portlanders are used to steering clear of the emerald-green water that materializes during warmer temperatures.

This year was supposed to be different. Thanks to legal action brought by environmental watchdogs, state regulators and the gravel mining company that owns much of the island crafted a plan to keep more of the algae contained inside the lagoon.

Conditions in the river over the past week raise questions about whether that stopgap measure is sufficient to protect public health.

As of Aug. 16, the Oregon Health Authority is advising people to avoid swimming and high-speed water ac