Indian Creek Floodplain Reset

Indian Creek is an important tributary to the Elwha River and was among the first sites colonized by anadromous salmon following the removal of Elwha Dam in 2012. Indian Creek has been colonized by chinook, coho, pink salmon, and steelhead. Through its monitoring programs, The Lower Elwha Tribe has documented a 0.5-mile reach of Indian Creek that had been channelized in the 1950s to support gravel extraction. Habitat conditions within the channelized reach are greatly simplified and were characterized as a plane-bed with no spawning habitat and minimal rearing habitat. Within a 0.2 section of the channelized reach, we conducted a floodplain reset or zero-stage restoration project to reconnect Indian Creek with its floodplain and restore natural processes. Using ground-based equipment the tribe removed standing trees from the push-up dike, placed those trees within the channel and active floodplain, removed the push up dike and utilized alluvium to equalize channel bed elevations allowing Indian Creek to naturally interact with its historic floodplain, and finally conduct floodplain revegetation. The Tribe is now in active planning to restore the downstream 0.3-mile untreated reach of Indian Creek.

This project will convert 0.5 miles of Indian Creek from a simplified plane-bed channel to multi-thread floodplain complex with high levels of in channel wood. This restoration will restore habitat forming processes and result in new spawning sites where there are currently none, as well as multiple pools for rearing where there are also currently none. The restored floodplain will have reduced hydraulic stress as peak velocities and bed shear will be reduced through the reach. Multiple species of salmon will use the restored reach including listed populations of chinook salmon, steelhead and bull trout.