Instream Restoration

Instream restoration projects help to improve North Coast streams by adding structures that mimic nature. Made primarily of wood and rock, these structures add complexity to the stream channel, provide shelter for both juvenile and adult salmonids, reduce water temperatures, and help to prevent stream bank erosion.

Constructing an Instream Structure

Instream structures create localized change in channel morphology, and provide habitat in streams where it is otherwise lacking. They prevent stream bank erosion by redirecting the force of the water towards the center of the stream and create habitat in the form of pools and instream cover.

An excavator places rocks and logs to form the structure.     Rocks structures are drilled in preparation for anchoring.     The rocks are anchored together with cable to withstand high winter flows.   A CCC crew anchoring a deflector on Yager Creek.   Logs are anchored to the rock structure with cable and re-bar.   Close up of a completed deflector.   A series of deflectors during winter flows.
Bull Creek Restoration Project 1999-2004
From 1999-2004 ERWIG has spent part of each summer working with the Humboldt Redwoods State Park implementing restoration projects in Bull Creek. Over thirty instream structures and riparian planting projects have been implemented along a four mile stretch of Bull Creek. These projects have increased boulder, log, and deep-water cover available to migrating adult and rearing juvenile salmonids; enhanced spawning gravels, improved water quality by protecting eroding stream banks; and lowered water temperatures through the development of a healthy riparian corridor.
	Vertical banks have been re-contoured to a more natural slope, and exposed, barren riparian areas have been planted with willow, alder, and conifer trees. Willow sprigs were planted, beginning at the normal bankfull height of the stream, followed by alder seedlings, and conifers on the floodplain terraces.
Approximately 1,500 native fir trees were planted throughout the project reach. Due to harsh site conditions, protective mulch and prepared topsoil were used when planting the conifers.