Fern Hill Forest Stream Restoration

Stability, habitat, and function are restored to an ephemeral stream in the Tualatin River Watershed, enhancing ecological connectivity in the Portland metropolitan region.

Spanning more than 262-acres within the Tualatin River Watershed, Fern Hill Forest is managed by the Metro Parks and Nature Department. In addition to oak woodlands and riparian and upland forest habitats, the site includes two ephemeral streams that flow to the Tualatin River and provide seasonal habitat for amphibians, mammals, and migrating birds. In converting an 88-acre hazelnut orchard on the property to an open meadow wildlife corridor, Metro sought to restore the landscape’s natural drainage patterns, improve wetland hydrology, and stabilize one of the ephemeral streams, which was actively eroding.

Biohabitats Construction implemented the restoration, which was designed by AKS Engineering & Forestry. This included removing and disposing of 2500 linear feet of agricultural drain tile, creating 1500 linear feet of new stream channel, and restoring 2000 linear feet of gravel access roads. In the new channel, Biohabitats Construction installed 12 beaver dam analogs, log jams on both streambanks, and a channel spanning log jam to enhance stream habitat, stability, natural hydrology, and ecological function. They also installed and maintained permanent erosion control measures.

The restoration helps Metro continue to enhance ecological connectivity, water quality, and habitat in the Tualatin River watershed.

TAGS

• Construction
• Ecological Restoration