Upper Clackamas River Habitat Restoration

The project experienced delays and changes due to the Labor Day fires of 2020. Working with the Mt Hood NF, ODFW, PGE and the Clackamas Partnership, the project was altered to focus on the lower 1/3 mile of the South Fork Clackamas River, a hotspot for Chinook and coho salmon spawning.

Using an excavator, 45 very large fire-killed conifers, predominantly Douglas firs, were tipped into the South Fork. The largest tree tipped was over 60 inches diameter and nearly 200 feet tall and all trees tipped were over 24 inches in diameter and over 100 feet tall. One large apex jam comprised of 12 trees was created at the lower end of the project on a nascent island in the SFK Clackamas to promote a branching channel. The other tipped trees were spaced along the river where the excavator could safely reach and tip the trees. 18 acres were treated for invasive weeds, which was not part of the proposed project but was ultimately included as the scope of the project changed in response to fire.

Clackamas River basin ESA-listed fish species, including Upper Willamette River Chinook, Lower-Columbia River Coho and Lower Columbia River steelhead are negatively impacted by loss of habitat, impaired water quality and lack of access to historic spawning areas, such as side channels. This project will restore habitat elements believed to be most limiting to these populations of salmon and steelhead as identified in local and regional assessments referenced above and in this application.

Lack of Large Wood: Limited pieces of large wood were noted by surveyors within the active channel area of the project reach. A lack of mature conifers within the riparian and upland areas limits future recruitment of large wood from those areas and it is likely there is little recruitment from upstream reaches given that the highway continues as you travel upstream of the project area. Large wood, especially key pieces are an important component of creating and maintaining physical habitat diversity for the ESA-listed fish. Significantly increasing the density of large wood in the project area would greatly enhance biological conditions for these fish. Large wood creates hydraulic roughness along the channel and, in turn, recruits gravels needed for spawning fish. Spawning fish depend on appropriately sized gravel and cobble that are not always found in a river devoid of the roughness provided by instream wood. Rearing salmonids also depend on in-stream and overhead cover for refuge from predators, Large wood provides refuge for juvenile salmonids, as well as a substrate where food resources tend to accumulate, in the form of macroinvertebrates.