“Fish are attracted to the lift because we use attraction water from the headpond and also the exit flume.  The headpond provides the bulk of attraction water.  The flume also adds attraction water but not so much for attraction at the entrance but to provide flow within the flume so the fish know which way is upstream.  You’ll recall that there are two massive 24” pipes that feed the diffusion chamber (where the super energy is sucked out of the water) one of these pipes runs the full length of the flume to the headpond where there is a valve we can control the flow from.  We also control the flow from the exit flume.  So, if by bubbling water, you mean the flow out of the entrance weir (where the fish come in to the collection chamber) they are attracted there because they seek a way upstream to their spawning grounds.

Nate Gray

So here we are at the base of the dam being drawn to the lift by bubbling water indicating the way upstream to the fish. How they negotiate this is an important part of their success in spawning. The goal to get the fish past the falls in good shape and ready to swim the rest of the miles to their spawning grounds.