The Challenges and Returns of Rehabilitating Stream Habitat within the Human-Modified Environment - A Case Study from Chico Creek, Kitsap County, Washington

Chico Creek discharges into Dyes Inlet on the eastern side of the Kitsap Peninsula in Kitsap County, Washington. Perhaps the most productive salmon watershed in the Kitsap Peninsula, Chico Creek supports regional populations of four salmon species, including chum, coho, steelhead, and cutthroat trout.  Thus the watershed also plays an important role in nutrient cycling, commercial and recreational fishing, as well as the diet of the ESA-listed Puget Sound orca.  Yet, the salmon in Chico Creek face many challenges for upstream passage, spawning, and rearing caused by hydromodifications and land use changes in the watershed. As a result, several channel reaches have become characterized by confinement, incision, high flood volumes and velocities, lack of large wood for habitat, lack of rearing and resting areas, and even failed restoration efforts. 

 In 2005, Kitsap County began working with Herrera to implement a multi-stakeholder approach to a number of projects in the vicinity of a quarter-mile-long reach of Chico Creek that runs through the Kitsap Golf and Country Club (KGCC). Historic channelization and armoring of this reach had contributed to severe degradation of salmon habitat, isolation of the channel from its floodplain, and conditions which inhibited salmon access to productive habitat upstream.

 Working in cooperation with Kitsap County, the KGCC, the Suquamish Tribe, the Kitsap and Mason Conservation Districts, and Washington Department of Fish and Wildlife, Herrera developed a design that could sustainably improve fish passage and habitat, improve the aesthetics and playability of the golf course, and reduce the flood and erosion hazards associated with pre-project conditions. Achieving these seemingly competing objectives involved close stakeholder collaboration to establish the design constraints. The channel needed to be self-maintaining so that incision or aggradation and the associated bank erosion or lateral migration did not produce a high maintenance channel that decreased golf course playability, compromised infrastructure, or decreased aquatic function. These constraints required redundancy in design, and robustness to account for unquantifiable factors such as the potential for an increased frequency of intense rain events.

 Phases 1 and 2 of the project were constructed between 2008 and 2010, resulting in an additional 580ft of side-channel habitat, the replacement of approximately 315ft of armored bank with vegetated coir slopes, and improved fish access to an additional 15 miles of stream. Although challenging to implement, the Chico rehabilitation efforts in the KGCC reach have ultimately promoted a feeling of ownership and stewardship for the surrounding community.