WRIA 31 Instream Habitat Assessment

Figure 5. Fish distribution within WRIA 31 from the WDFW SaSI Report (WDFW 2002,http://wdfw.wa.gov/fish/sasi/)‘ The Forest Service manual codes for the field forms were modified – the ForestService manual uses some difficult to remember coding; more memorable codeswere used for this project.‘ Walnut was added as a tree species potentially occurring in the project area (walnutis common in riparian areas of portions of Rock Creek and Chapman Creek).At each randomly selected segment, individual channel units were identified (a channelunit was defined as a pool, riffle, glide, braid, or dry segment; side channels weredocumented separately from main channel units). Data collected for each streamsegment and each channel unit included the GPS location for the top and bottom of thesegment, bankfull width, maximum bankfull depth, three separate estimates of averagebankfull depth (calculated as the average depth across a transect), width of the innerriparian zone (defined as extending from the stream to a point where vegetation changesto a more upslope character), dominant and subdominant plant species within the innerriparian zone, average overstory height, average understory height, canopy closure,stream gradient, and dominant and subdominant plant species in the outer riparian zone(defined as the area between the inner riparian zone and a point 75 feet from the bankfulllocation), and the presence or absence of unstable banks, hydromodifications, barriers,and factors affecting riparian condition (such as cattle or roads) (Table 1). Photos of eachtransect were taken to document sites.WRIA 31 Instream Habitat Assessment 9 Watershed Professionals Network