The West Side Big Pipe Project

Construction is complete on the West Side CSO Tunnel, which is a 14-foot diameter, 3-1/2 mile long tunnel that will capture sewage and stormwater on the west side of the Willamette River.  The tunnel extends from SW Clay Street to Swan Island. 

Site restoration has happened at all five West Side Big Pipe tunnel shafts. The shafts connect the existing sewer system to the new tunnel and is being used for long term operations and maintenance access. 

Lewis and Clark, the tunnel boring machines (TBMs), began excavation from the Nicolai Shaft.  Lewis completed the journey north, under the river to the Confluent Shaft and then to the Swan Island Pump Station Shaft.  Clark completed its journey and broke through on July 29th, 2005 at the Clay Street Shaft. This work is complete and the tunnel became 100% operational in December 2006.

 West Side CSO Program - 24 min video