A 'Bubble Barrier' is trapping plastic waste before it can get into the sea

>It traps 86% of the trash that would otherwise flow to the River IJssel and further on to the North Sea, according to Philip Ehrhorn, co-founder and chief technology officer of The Great Bubble Barrier, the Dutch social enterprise behind the system.

>Commissioned by the municipality of Amsterdam and the region's water authority, the Bubble Barrier was installed in October 2019 in under five hours.

Another idea I’ve seen is a trash interceptor: https://en.wikipedia.org/wiki/Trash_interceptor