Fish Habitat Improvement
Before Large Woody Debris (LWD) Installed
One of the techniques used to restore salmon habitat is the installation of large woody debris (LWD). Streams need a variety of habitats to support rich biodiversity.
Many streams in the Tualatin Watershed lack this structure because of the lack of LWD. The LWD would normally be provided by intact stream-side forests. However when the forests were harvested, the LWD disappeared.
After Large Woody Debris (LWD) Installed
Large woody debris stabilizes steam channels by reducing water velocity, creating pools, and reducing bank erosion.
It provides cover, resting, and feeding areas for juvenile fish. It traps gravel and nutrients and sorts fine and coarse sediments. This results in better spawning opportunities.
Two culverts and road fill were removed to allow fish passage to upstream habitat. In addition 208 logs were placed in the streams by helicopter to produce additional fish habitat. Native plants were planted on both sides of the stream and on a upland site following the in steam work. Continue reading
This project along Gales Creek decommissioned a farm road, added large woody debris to improve fish habitat, planted native plants in the newly created riparian and flood plain areas. It also created several depressions for amphibians along the stream corridor. Continue reading
One hundred logs were placed in the stream in groups of 3 to 8 to produce in-stream habitat for native winter steel-head and cutthroat trout and non-native Coho salmon. Continue reading
Over 170 whole trees were placed in selected areas to create pools and smaller additional channels. These will provide refugia areas for native fish and help retain gravels in this area of the stream system. Continue reading