Summary: Lost Creek, a tributary to the North Fork Nehalem, had several problems related to fish passage, in-stream complexity, and riparian condition that were limiting salmon production.
A collapsed log stringer bridge prevented adult and juvenile coho, steelhead, cutthroat, pacific lamprey, and brook lamprey access to the upper 1.8 miles of habitat. Cabled remnants of a splash dam 420’ above the mouth had created a jam that was preventing juvenile and lamprey passage. Past use of splash dams created alder dominated flat terraces and limited in-stream complexity. The riparian area was conifer deficient for shade and future large wood recruitment.
The Lost Creek basin is adjacent to the God’s Valley basin, a highly productive coho area where several habitat restoration and enhancement projects have occurred.
For the stringer bridge removal, log and boulder structures were installed downstream of the bridge site to capture released bedload material. Logs from the bridge itself were used in some of the structures. This work was done using two excavators in tandem, increasing efficiency. After the bridge was removed, the banks were “pulled back” or slightly graded, and straw was spread over any exposed soil for erosion control. Concurrent with the bridge removal, large wood placement took place in the lower reaches of Lost Creek.
A steep, V shaped valley form prevented equipment access to the stream in this area, so a yoader (combination yarder/ loader) and cable system was used to yard the logs into the stream. Once the stringer bridge portion of the project was complete, log structures were placed using the excavators in areas where the equipment could reach the streambank.
In all, 40 structures were installed consisting of 110 key pieces plus additional smaller material. Riparian planting followed the winter after the in-stream work was completed. Both sides of the stream were planted along the project area, according to the site-specific conditions and plantability of the site. Equipment corridors were planted as well. In total, 500 Western hemlock, 1500 Sitka spruce, and 2000 Western red cedar were planted at Lost Creek.
Status: Completed April, 2009
Partners: Longview Timber, Oregon Dept. of Fish and Wildlife, Oregon Dept. of Forestry, Oregon Watershed Enhancement Board, US Fish and Wildlife Service, Native Plant Coop