Further Studies on Fishway Slope and Its Effect on Rate of Passage of Salmonids
Bonneville Dam, chinook, Dalles Weir crest, fish passage, Oncorhynchus tshawytscha, pool, rate of passage, salmon, salmonids, slope, steelhead, trout, weir
Journal or Book Title
The rates of passage of chinook (Oncorhynchus tshawytscha) and sockeye (O. nerka) salmon and steelhead trout (Salmo gairdneri) were studied in 1:16- and 1:8-slope, pool-and-overfall fishways. In general, the passage of salmonids through the 1:8-slope fishway was a 1.0-foot rise between pools was as fast as, or faster than, in the 1:16-slope fishway with a 1.0-foot rise. When the rise between pools was increased to 1.5 feet in the 1:8-slope fishway, chinook and sockeye were slower. The 'Dallas-type' weir crests in a 1:16-slope fishway appeared to accelerate chinook passage. Chinook and sockeye displayed seasonal differences in times within species.