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When Willie Levenson moved to Portland three decades ago, he very quickly learned how locals related to the river flowing through the middle of their town.
“I was indoctrinated with, ‘Welcome to Portland: it rains a lot, and never put your toe in the Willamette because your skin will flake off, you’ll grow horns, your skin will turn neon green,’” said Levenson, who formerly led the river advocacy group Human Access Project.
Back then, swimming in the Willamette was unthinkable. The river had been closed to the public for swimming since 1924 due to sewage pollution, and poking fun at the river’s degraded state was not merely acceptable, but almost a “point of pride,” Levenson said.
But beginning in 2011, when the city completed work on its $1.4 billion Big Pipe sewage overflow project, things began to change. Slowly but surely, thanks in large part to the work of Levenson’s Human Access Project, people started to view their relationship with the river differently.
The early driver of that change was, for many, the Big Float—a summer festival on the river in downtown Portland that Levenson organized, which he described as a “movement disguised as a party.” The Big Float ceased operations four years ago, leaving in its wake a network of beaches and piers that hum with activity throughout the summer.
These days, Portlanders are eager to swim in the Willamette. The biggest obstacle to river health and access now is not sewage or outdated public perception, but something else: algae blooms. The blooms, which are caused by increases in the amount of cyanobacteria in water, can cause rashes, indigestion, and even neurological issues.
Last August, as often occurs in late summer, the Oregon Health Authority issued an advisory for an algae bloom that emerged in the Ross Island lagoon and spread to other parts of the river. To Levenson and other advocates and scientists familiar with the river, the fact that the bloom originated in the Ross Island lagoon came as no surprise.
Algae blooms thrive in stagnant water, which is exactly what the Ross Island lagoon is. It was built by the Army Corps of Engineers in the early 1920s in order to block water flow and allow Ross Island Sand & Gravel to mine gravel from the Willamette, which it did until 2001. The lagoon currently has no fresh water flow.
Harmful algae blooms also become more frequent as the weather gets hotter, and the combination of warmer summers due to climate change and stagnant water threatens to keep people out of the river during the months most want to use it.
The issue is serious enough that, at this point, the fate of the Ross Island lagoon has become Human Access Project’s primary focus.
“With our mission to transform Portland’s relationship with the Willamette River, if there’s consistently a harmful algae bloom in the lagoon that impacts all of Portland, then everything we’re doing is frivolous,” Levenson said.
Desirée Tullos, a professor at Oregon State University who has spent years working on Ross Island, said that in the push to contain the harmful algae blooms, time is of the essence.
“If we don’t address it, the problem is going to continue and it’s going to get worse,” Tullos said. “We’ll continue to see the entire river turning green. My fear, bigger picture, is that people will start to turn their back on the river again.”
The Human Access Project has gotten behind a proposed solution of engineering a channel in the lagoon to allow fresh water to flow in.
Part of the problem? Opening up the lagoon won’t be cheap. It’s estimated to cost $14 million to open up a single channel in the lagoon for fresh water. A second channel raises the cost estimate to $26 million.
Perhaps more significantly, Tullos said, is the reality that no single party bears all of the responsibility for the algae bloom issue. It’s the result not just of the creation of the lagoon, but also of climate change and the concentration of nutrients in the watershed.
Progress towards funding the construction of channels into the lagoon has been slow. A bill proposing to allocate $1 million to project planning died in the state legislature last year.
In the meantime, another proposal for Ross Island has gained traction. A group of private interests involved in the Portland Harbor Superfund site proposed purchasing Ross Island from Robert Pamplin Jr., who also owns Ross Island Sand & Gravel, and filling the lagoon with materials from the Superfund site.
The alternative plan has a clear financial upside. State taxpayers are responsible for a significant portion of the cost to clean up the Superfund site. The original plan for Portland Harbor, which would involve shipping contaminated sediment to landfills in Central Oregon, has been previously estimated to cost as much as $4 billion.
The proposal to instead use some of the sediment to fill the hole at the bottom of the lagoon could significantly reduce the cost of cleaning up the Superfund site. The savings could potentially be used to ecologically restore Ross Island and even place it in public ownership.
Environmental advocates have urged Gov. Tina Kotek to consider the Superfund proposal in a “robust, transparent public process” with “rigorous science-based analysis led by neutral parties.”
Tullos, however, says the Superfund proposal would require delaying channel construction, and that in the meantime, it could actually exacerbate the algae bloom issue. She pointed out that during the time it would take to dredge and place the Superfund materials at Ross Island, it’s important to restrict water flow in and out of the lagoon in order to prevent the sediment from contaminating the rest of the river. This, however, would keep the water in the lagoon stagnant—ideal conditions for harmful algae formation.
“Filling the lagoon with sediment is not proposed as a means to address the bloom…. The reason it is being proposed is because they need a place to put the Superfund materials,” Tullos said. “There’s some conversation about this being an elegant solution, and I don’t think it’s quite as elegant as people are saying.”
There’s plenty on the line, not just from an ecological perspective, but also from an economic one. According to a recent study from consulting firm ECONorthwest, the river is responsible for hundreds of millions of dollars of economic activity in the region annually. More and more, people are seeing a healthy Willamette River as integral to Portland’s culture—which was Levenson’s goal from the start.
“I didn’t just do the Big Float to throw a party,” Levenson said. “The whole point was to develop a culture around caring for the river and viewing it as an asset.”
