Rainbow trout, 2020

Study Overview
Scientific partner:
Pacific Northwest National Laboratory
Rainbow trout
Fish length:
200-400 mm (8-16 in)
RHT runner:
1.9 m (6 ft) diameter
5 m (16 ft)
Rotational speed:
130 rpm
Turbine-passed fish:
Control fish:
100% immediate and 48h survival of turbine-passed fish

Rainbow trout (Oncorhynchus mykiss) are an important representative salmonid and are one of the most studied species with respect to the effects of hydropower and dams. The sea-run migratory variety, known as steelhead, is a critical species affected by hydropower development on the Pacific coast.

Rainbow trout have been an important species in the development of Natel's approach for fish-safe turbine design, too. We conducted our first fish-safety tests in collaboration with Alden Laboratory, to examine the effect of blade strikes on rainbow trout ("Improving Survival: Injury and Mortality of Fish Struck by Blades with Slanted, Blunt Leading Edges"). We have continued to work with the species through a series of turbine passage studies involving different-sized trout and turbines, and different turbine speeds, both in our laboratory in Alameda, CA, and in our field installation in Culver, OR.

The following video details a study conducted in the field at the Monroe Hydro Plant in Madras, OR, in collaboration with PNNL.