This is pretty neat. Perhaps a little enviro-gimmicky but still cool.
https://www.youtube.com/watch?v=v5l7s6wC50g
https://www.youtube.com/watch?v=v5l7s6wC50g
Seems amazingly complex for no reason. A post in the waterway with a floating line across the top of the waterway would do the same thing (skim the top of the water). Angled off to the side, the current should drag all the objects right into a collection area.
Well it does have a bit of a rube goldberg feel to it.