[cocoapuffs7]

If this is the main idea, move it further up on the page if it doesn't break your design goals. I skipped the initial text and went right to it.

https://thegreatbubblebarrier.com/wp-content/uploads/2018/03...

Great idea. Has it been tested?

[DoingIsLearning]

They claim they are working with Deltares which if you are not familiar is a reference research institute in the Netherlands for Waterway management.

On top of the principle you linked I think an important feature of their concept is that the bubble barrier is diagonal to the waterway so that the debrie is accumulated and guided to a single collection point on the river bank.

[maaaaattttt]

There is a video [0] on the "more info" page [1] that presents one working implementation in Amsterdam (video is in Dutch but with good subtitles)

[0] https://www.youtube.com/watch?v=n_KwF-gf0S0

[1] http://thegreatbubblebarrier.com/en/amsterdam-en/

[moooo99]

I know that big chemical manufacturing facilities with waterway connections use a similar approach to keep chemicals from entering the waterway in case of an accident. So when it works for liquids, I'd assume it'd also work for solid objects such as plastic waste. However, I doubt this is something fishes would pass, I couldn't find anything about that that proves this claim.