The design approach involved removing the plug that blocked flow into the secondary channel and installation of channel-spanning log weirs on the main channel. These treatments resulted in reduced velocities and shears on the mainstem and aggradation of coarse bedload on the main channel, allowing for restoration of a more natural pool-riffle morphology. The project was constructed in September 2009. Monitoring of the site since 2009 has shown a steady improvement in the bed morphology of the channel as the supplied coarse bedload is deposited through the project reach. Wetland habitat is also developing in the side channel as the water table increases due to aggradation on the main channel.
Gooseneck Creek Restoration
Client: Yamhill Basin Council
Gooseneck Creek, tributary to Mill Creek and the South Yamhill River, is an important tributary for steelhead/coho salmon spawning and rearing. The project area is located above the confluence with Mill Creek in a portion of the channel that was historically impacted by aggregate mining. Waterways was contracted by the Greater Yamhill Basin Council to develop a restoration design for approximately 2,000 feet of Gooseneck Creek that was incised down to bedrock due to past mining activities and historic plugging of a secondary channel. Confinement of the channel, in-channel mining activities, and loss of secondary channels had all but eliminated the natural pool-riffle morphology with a consequent loss of aquatic and riparian habitat.