Willamette River CSO Projects


Portland, Oregon 


Portland Bureau of Environmental Servicees 

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Winterbrook served as consultant lead for land use, environmental, and greenway planning and permitting on a series of BES projects designed to remove Combined Sewer Overflows (CSOs) from the Willamette River. This is also known as the Big Pipe Project. Two of these projects are highlighted below; they are among the largest public works projects in Oregon.

East Side CSO Tunnel, Shafts and Pipelines

This project extends 5.5 miles along the east side of the Willamette River.  Winterbrook coordinated closely with local, regional, state and federal agencies to ensure that permits were acquired in a timely and systematic fashion.  Key permitting agencies included: Union Pacific and private railroads, US Army Corps of Engineers, US Fish & Wildlife Service, DSL, DEQ, ODFW, ODOT, Metro, PBOT, BES, PWB, PP&R, and BDS.  Winterbrook also prepared and obtained approval for a comprehensive land use review package.  Winterbrook provided technical support for permit compliance and landscape plan implementation through completion of construction in 2011.

West Side CSO Tunnel, Pipelines and Pump Station

This tunnel extends 7 miles along and under the river, terminating at the Swan Island Pump Station.  Winterbrook provided agency liaison services, coordinated local, state and federal planning and permit strategies, and prepared environmental, land use and other required permits for the project. The permit team successfully avoided major land use permits (e.g., Conditional Use) and obtained expedited permit approvals from the City for the entire facility. Winterbrook also completed the Greenway Permit application and supporting documentation, and obtained permit approval for the Swan Island Pump Station.

See the City’s project website here.