Twelvemile Creek is located on Prince of Wales Island, approximately nine air miles southwest of Hollis and eight air miles northeast of Hydaburg, AK (Figure 1). Historically, Twelvemile Creek has provided high quality spawning and rearing habitat for coho (Onchorhynchus kisutch), pink (O. gorbuscha) and chum (O. keta) salmon, as well as steelhead (O. mykiss), cutthroat trout (O. clarki), and Dolly Varden char (Salvelinus malma).
Stream channel restoration, including large wood additions, occurred in Twelvemile Creek to accelerate the recovery of watershed processes, stream channel conditions and salmon, steelhead and cutthroat trout productivity. The restoration was conducted in the summers of 2012 and 2013. During the winter of 2014, two peak flow events occurred in Twelvemile Creek resulting in stream channel adjustment and habitat changes. Large volumes of wood and sediment moved during these events as the new addition of wood adjusted to the high flows. This report discusses the restoration design, the flood event, the channel response to that event, and lessons learned. This report will only briefly refer to habitat data that’s been measured. For a full summary of habitat survey data collected to date, please refer to the Twelvemile Creek Mainstem Instream Restoration Monitoring Summary (USFS 2015).