It's complete and working in that water passes through it. Unfortunately, we won;t know if eels are using it simply because we don't have a trap (was impossible due to the structure of the weir) fixed at the head to do eel counts. There is a camera, forget what it's called, that can view eels passing through as white streaks, but they cost, I'm told, around £50,000 so that's not practical even.
The only thing we could do is put signs in the water pointing them to the entrance. :wh OR - there are some tiles we could put on the river bed that eels love to sit in until they decide to ascend the tube. They're about £25 each so we'll see if if can get some volunteers and the EA to help install them.
PS: You've reminded me, I have to progress with another one now, but will see about installing some tiles.