The Mason Creek watershed supports populations of Chinook, Winter and Summer Steelhead, Coho, Chum, Pacific Lamprey, and Cutthroat Trout, which are limited by degraded spawning and rearing habitat conditions. This is due to a variety of factors, but most notably the historic removal of instream and riparian wood and trees, loss of willow communities due to timber herbicide runoff, the trapping of beaver, and invasive non-native riparian plants (primarily reed canary grass). These factors limit instream complexity, frequency of overbank flow/floodplain connectivity, and health of riparian areas, all of which limit production and productivity for the impacted populations. These factors have also accelerated the drainage efficiency of the system, exacerbating low summer flows and the likelihood for the creek to run dry during the summer. For all species, the increasing seasonality of the creek is a huge limiting factor. This area was well known as a prolific beaver region and contained several extensive beaver complexes spanning several miles. These areas stored enormous volumes of water and provided essential rearing habitat for juvenile salmonids. The dams protected spawning gravel downstream by retaining fine sediments, which made perfect spawning habitats behind the dams for pacific lamprey. The lamprey ammocoetes, in turn, served as a key food supply for the salmonids. Today these beaver ponds are largely abandoned due to a loss of willow and possible trapping. However, they persist as some of the only areas that remain wet during peak droughts despite massive reductions in storage capacity. While other changes in land use practices have undoubtedly played a role in the creek’s shift in seasonality, the loss of beaver was likely a major contributor. Outside of the beaver areas, the creek struggles with structural starvation, channel incision, floodplain disconnection, and simplified riparian habitats. This project will address these limiting factors by increasing in-stream structure and habitat complexity, restoring the beaver ponds, management of invasive reed canary grass, and enhancement of riparian communities. These actions will improve sediment sorting, increase habitat complexity with greater pool and bar frequency, increase floodplain and side channel connectivity, expand juvenile rearing habitat, and improve spawning habitat.