How big can a fish be and still pass through the Restoration Hydro Turbine (RHT) safely? Pretty big! This passage test of 186 rainbow trout measuring up to 500 mm (~19.7 in) in length found no meaningful difference between the fish passed through a 1.9 m (~ 6.2 ft) diameter RHT and the control group, who were not passed through any turbine.
This fish passage test was conducted jointly by Natel Energy and Pacific Northwest National Laboratory (@PNNL) in the spring of 2022, at Natel's Monroe hydropower plant in Culver, Oregon.
For more info about Natel's fish passage testing and peer-reviewed papers, visit our fish passage page.
Read Abe Schneider's opinion piece in The Ontario Waterpower Association's 2022 Year in Review about why Canada needs hydro turbines that are safe for fish to pass through.