BPA, in collaboration with the Nez Perce Tribe, worked with FSP’s engineers to design and provide construction support services for an in-channel picket weir barrier, trap, and sorting facility for spring Chinook salmon and steelhead on the Lostine River. Key project elements included: alternative formulation; location siting; conceptual development; hydraulic/hydrologic analysis; final design; preparation of final construction documents; preparation of probable construction costs; environmental permitting and extensive agency coordination; fish salvage support during construction; bid support; contract management; and collaboration with fisheries resource managers such as NOAA and the Nez Perce Tribe.

The potential for flashy high flows along with concerns of adjacent property owners relative to inundation and streambank erosion potential presented special design challenges. The picket weir assembly was designed with a low concrete sill, control of picket weir panels using a hydraulic lifting mechanism, and overflow spillway for extreme hydrologic events. The weir design was also automated to react to a variety of emergency situations such as debris accumulation using integrated water level and pressure differential sensors.

The trapping facility design consists of a single vertical slot controlled fishway, fyke panel, and staging pool. Guide slots were provided for fykes, screen panels, and stop logs to customize the configuration and allow for separation and volitional release  of non-target fish species such as bull trout. All designs were coordinated with NOAA, USFWS, and ODFW regarding fish passage, trapping, and handling criteria.

Special features were incorporated into the design to facilitate handling of bull trout and steelhead. All long term and construction related impacts to the natural environment were mitigated on-site.

Proposed schedules were adjusted during the project, as necessary, to accommodate changes in the permitting strategy, as well as accommodate stakeholder reviews and agency reviews. The preliminary schedule milestones, with regard to delivery of the final project, were met so that compliance could be achieved.