OK if you can get fish over the dam can the smolt get safely back down stream?
The answer is Yes!
THIS DOWNSTREAM SMOLT SYSTEM CAN GET SMOLT
OVER FOLSOM DAM ON THEIR RETURN TO THE PACIFIC OCEAN TO MATURE!
IT IS IN USE ON THE NORTH FORK OF THE CLACKAMUS RIVER NOW.
North Fork Development is located about 14 miles downstream of the Oak Grove powerhouse and is the most upstream of the three developments on the Clackamas River. The powerhouse is integral to the concrete arch North Fork dam. The North Fork Development includes the upstream terminus of the 1.9- mile-long North Fork fish ladder that contains an existing adult fish trap and sorting facility. It also includes a juvenile fish collection that screens and bypasses downstream migrating fish around the dam and powerhouse and into the North Fork fish ladder. The bypassed fish travel about 1.5 miles downstream through the fish ladder to a downstream separator where they are diverted into a holding tank, identified, and counted. Downstream migrants are then released into a 5.1-mile-long bypass pipe that carries them downstream to where they are released into the Clackamas River below River Mill Dam.
See the full report here for mor details: Clackamas Hydroelectric Project Final Report