The most recent Natel/Pacific Northwest National Laboratory test of 186 large rainbow trout measuring up to 500 mm (19. 7 inches) in length, found no meaningful difference between the fish passed through Natel’s 1.9 meter (roughly 6 feet) in diameter turbine and the control group, indicating that the RHT allows safe passage of some of the largest fish ever successfully passed through a compact hydro turbine.
The NHA's Powerhouse published an insightful article by VP of Public Affairs Kate Stirr discussing the challenges and solutions to ensuring safe passage for eels through operating hydropower plants.