Relative Passage Survival and Injury Mechanisms for Chinook Salmon Smolts within the Turbine Environment at McNary Lock and Dam, Columbia River
chinook, Columbia River, entrainment, injuries, juvenile, juvenile salmon, mechanisms, model studies, Oncorhynchus tshawytscha, salmon, smolt, survival, turbine passage, wicket gate, Army Corps of Engineers, releases
None supplied. From executive summary: As part of the Turbine Survival Program, survival probabilities (1 h and 48 h) of hatchery-reared chinook salmon, Oncorhynchus tshawytscha, (average total length about 1.54 mm) were estimated at McNary turbine Unit 9. The primary objectives of the study were to: (1) estimate survival rates of juvenile salmon introduced near the turbine hub, blade tip, and stay vane/wicket gate relative to those introduced near the mid-blade region, and (2) better understand the factors and mechanisms contributing to injury/mortality of turbine passed fish. The turbine passage tests were conducted with the unit operating at nearly constant blade angle (25.22º) and wicket gate setting and within 1% of maximum efficiency. The four release locations were chosen based on the results of a hydraulic model study at the U.S. Army Corps of Engineers Waterways Experiment Station which indicated that injury/mortality risks vary with fish entrainment locations within the turbine environment. The proportion of alive recaptured fish ranged from 0.919 for the blade tip release to 0.936 for the hub releases. The proportion of fish recaptured dead was lowest for the mid-blade region (0.016) and similar for all other release locations (0.030 to 0.032).