Portland, Oregon settlement provides $19.5M for Columbia Slough cleanup

The Oregon Department of Environmental Quality (DEQ) announced that it will receive $19.5 million over three years from a settlement with the City of Portland to help address stormwater discharges and sediment contamination in the Columbia Slough waterway.

“This up-front funding will help cleanup happen more holistically and move forward in a way that will better support shared remediation goals, protect public resources, and bring the community into the restoration process,” said DEQ project manager Sarah Miller.

DEQ held a public process for the settlement in November 2023 and Portland City Council voted to authorize the settlement agreement at a meeting on Jan. 24.

To complete cleanup project work more efficiently, DEQ and the city agreed to move forward with a settlement approach.

The settlement is part of DEQ’s Columbia Slough Sediment Project, established in 2005 to address contamination of the waterway.

The settlement from the city will include:

• Funding to design and construct cleanup actions in high priority sediment areas.
• One slough-wide sediment and fish tissue sampling event.
• Evaluation of all City-owned stormwater basins to prevent pollution from reaching the slough.
• Construction of 15 stormwater treatment projects at priority stormwater basins.
• Watershed habitat and health improvement projects, chosen in consultation with the community, with a focus on environmental justice opportunities.
  
  

The city will complete its work within the next 15 years. After completion, DEQ will release the city from liability for historical discharges to the slough.

A history of development along the banks of the Columbia Slough has led to an accumulation of contamination in the sediment and in fish, damaging the ecosystem. Since 2005, DEQ and the city have worked under a series of five-year agreements to evaluate different sources of contamination to the Columbia Slough that travel through city stormwater systems.

In 2008, DEQ created a settlement framework for parties to settle their liability for Columbia slough settlement contamination. Funds go to a state fund dedicated to sediment investigation and cleanup of priority areas within the Columbia Slough.

The City of Portland is one of many responsible parties, because contamination can travel through its stormwater infrastructure into the slough.