Habitat Enhancement

Some estimates show that natural systems have as much as 100 to 400 pieces of large woody debris per mile of stream.  Urban systems have virtually none.  When this project was completed, we had re-created a system much closer to the wild.  The planting of many trees along the stream assure that there is wood recruitment into the stream for many generations to come.

This project would not have been possible without the landowner who wanted to do something for salmon populations in her back yard.  We provided large woody debris structures as in-stream habitat. Each log was placed by an excavator to accommodate a variety of flow regimes.  Once placed, the logs were anchored into place using a variety of techniques.  Since North Creekís water levels rise rapidly after rain events (a common problem in urban watersheds), an added benefit created by these structures will be slower flows which will help prevent erosion.

Restoration in an Urban Watershed

Pre-project downstream view This stream corridor has good native vegetation on the left bank, but none on the right bank. The channel was a straight run.	Post-project upstream view The LWD manipulates the thalweg, creating diverse habitat in this 150 feet of stream. Pools and quiet edges began forming immediately.

Delivery of logs to be used in project Many of the logs used in this project were salvaged from old booms.	Excavator placing large woody debris	Placing earth anchors Earth anchors were driven 8 feet underground to stabilize the LWD structures. This is important in an urban watershed where downstream considerations include culverts and other road crossings.	Cabling of earth anchor

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