I have seen other countries use netting at the end of canals to catch the litter from going into the river. Either partner with an organization to install such a net or do a demonstration over the course of several days/weeks to see how much trash it captures. We could also investigate the trash robot of a previous project and do cross-promotion of these canal cleaning efforts.
Canal Nets

Idea:
Benefit:
The canals and river are so beautiful and historic but hard to keep clean, these seem like a simple tool to help with this problem.
Location:
I love this idea!