For thousands of years the north reach of the Willamette River, near its confluence with the Columbia, was a braided river of shallow channels and islands rich in biodiversity. That was until European settlers came to the Pacific Northwest and displaced the Indigenous people who had made this place their home since time immemorial. With industrial development, channels were filled, or dredged to create shipping lanes. Banks were hardened. Industries contaminated the water and land along the river, destroying salmon runs and reducing wildlife populations that had thrived alongside indigenous communities.

Today the area is designated an industrial sanctuary, but the communities that were displaced or damaged by this so-called sanctuary see it as an industrial sacrifice zone. Once a Braided River tells the story of the river before it was transformed into a Superfund Site and features community groups and activists working to replace the current Industrial Sanctuary with a green working waterfront defined by good jobs, clean energy, and healthy ecosystems. The documentary explores their vision to reclaim this stretch of river as a place where people and wildlife who depend upon the river for their homes, jobs and migration routes can thrive.