Cispus River-Yellowjacket Creek Restoration Project
Partnership and collaboration are key to improving watershed function on the Gifford Pinchot National Forest. The Forest is currently partnering with The Cowlitz Indian Tribe to improve salmon and steelhead habitat for Threatened coho, Chinook and steelhead in the Cispus River and Yellowjacket Creek, tributaries to the Cowlitz River.
Minimal high quality side channel spawning and rearing habitat exists in the Cispus River and Yellowjacket Creek. The project area falls short of its natural fish production potential due to natural, and human-caused disturbance. Major natural events have affected the Cispus River watershed, including ash from the 1980 eruption of Mount St. Helens, widespread turn-of-the-century fire, and multiple flood events. Past land management practices focused on timber production as it harvested much of the available standing large trees up to river’s edge and removed wood from stream channels.
Cispus River-Yellowjacket Creek Restoration Project, Phase I
The Cispus River-Yellowjacket Creek Restoration Project, Phase I is the first of a series of planned stream restoration projects in the Camp Creek-Cispus River and Yellowjacket Creek priority subwatersheds. Phase I restored a half mile section by adding 18 large complex wood structures at the confluence of the Cispus River and Yellowjacket Creek. The engineered log jams are embedded 20 feet into the riverbed and rise another 10 feet above the water surface as layers of large wood and slash.
Much like a naturally formed log complex, the structure is backfilled with river substrate. It was then planted over with native trees by Cascade Forest Conservancy volunteers, to help hold the structures in place.
This construction sequence is meant to mimic the decades of natural channel evolution that occurs when debris and sediment to collect around a giant fallen log, resulting in healthy, functioning floodplains and riparian forests. Some short-term response of engineered log jams will shift the river channel slightly, re-establish side channels, and create pools of deeper, cooler water where fish can survive and find refuge during periods of warming or floods.
Over time the project will provide quality spawning, summer rearing and overwintering habitat. Engineered log jams also provide high-quality hiding cover and increased residual pool depths in the main stems and re-activated side channels. Habitat in this reach can be utilized by Chinook, Coho, and Steelhead.
In addition, the project will improve water storage and hyporheic exchange, lower summer stream temperatures, and build resiliency to impacts of climate change, including increased magnitude of flood events, lower summer flows, and increased thermal pressure.
Large log jams are necessary for structures to stay in place, with yearly discharge in the Cispus River above the Yellowjacket confluence reaching about 15,000 cfs; with 28,000 cfs the current gaged maximum.
Approximately 18 log jams (90-150 logs each, 1,200 logs with root wads total) were added to the stream channel, side channels, and associated floodplain of the Cispus River and confluence with Yellowjacket Creek.
Project implementation took place during summer of 2020 and 2021 and project cost was well over $2,000,000. Funding was primarily from the Lower Columbia River Salmon Recovery Fund, with the Forest Service contributing retained receipts funding and trees for the project.