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This study was conducted to provide a baseline and preliminary understanding of the food web and physical habitat of Rufus Woods Lake (RWL), a run-of-the-river hydropower reservoir located downstream of Grand Coulee Dam, so that the rainbow trout fishery can be more efficiently managed or enhanced. A laudable goal for RWL is to create a sustainable fishery. However, a myriad of information is needed to fully understand a complex and rapidly changing reservoir such as Rufus Woods Lake. Commercial net pens are used in RWL within Colville Confederated Tribal jurisdiction to rear and in some cases intentionally release sterile rainbow trout (RBT). Determination of possible net pen effects was not the primary goal of this study, although positioning of sampling locations was performed throughout the reservoir with consideration to net pen location. Generally conditions for rearing RBT in net pens are good in RWL. However, high river flow years and operating practices of Grand Coulee Dam have resulted in supersaturated dissolved gas, gas bubble disease of aquatic organisms and severe mortality of the pen fish used for enhancing the fishery and for commercial fish farm production. As most of the fish caught in the RWL fishery are from net pen origin, the net pens are considered an important tool for managing the RBT fishery. Presently, relatively large size RBT released by the CCT into RWL are purchased from net pen grower