American eel, conducted with Pacific Northwest National Laboratory, Fall 2021

Study Overview
.55 m (1.8 ft) diameter RHT at 10 m (33 ft) head, 667 rpm
131 treatment, 43 control releases
American eel, 339-655 mm (13-26 in) length
100% immediate and 48h survival of turbine-passed fish

The American eel (Anguilla rostrata) passage testing we conducted with PNNL at our hydraulic test facility in Alameda, CA, in the fall of 2021, was designed to evaluate both the immediate and 48-hour survival rate of American eel passing through the RHT. We also looked at sublethal and behavioral effects of eel passage through the RHT operating under the most extreme conditions (maximum velocities, largest eel size relative to turbine).

We successfully captured high-speed video of 89% of passage events, which revealed an absence of pinching or laceration injury risk within the turbine. This work is summarized in a journal article published by the Transactions of the American Fisheries Society in August of 2022.