Canals & River Cleaning
For years there have been many attempts to clean up the Chao Phraya River and Bangkok's 'khlongs' (canals) as well as those in the vicinity, but it remains a massive ongoing struggle.

A whole fleet of clean-up vessels can be seen anchored near Phra Phuttha Yodfa Memorial Bridge.

They look quite impressive!

Unfortunately I haven't really seen them in action.

I wonder how much garbage they can collect before reaching their capacity.

They reminded me a little of the Mississippi paddle boats from days gone by...

Goodbye to the Chao Phraya River and let's have a look at my area in Nonthaburi.

Here the water hyacinths on Khlong Mahasawad have gone ballistic...

A smaller clean-up boat.

Plastic garbage remains a serious issue.

Taking care of equipment can be problematic as well.

Not sure how functional this thing still is...

A lot of work awaiting you blue guy!
Postscript

Chao Phraya River Slum community
Authorities tend to blame illegal communities living on canal banks for most of the pollution but it's a complex issue. People have been living there for many years in most cases but lack official documentation which leaves them outside regular plumbing, electricity, and other services.
Some communities have taken initiatives to tackle the garbage problems which is a good start.
Anti-littering campaigns have been launched from time to time at schools and communities but it's a slow process, I remember this when I was living as a kid in Holland as well.

Khlong Saen Saeb canalside community
Here are some links providing more details:
https://www.bangkokpost.com/thailand/special-reports/665456/the-great-khlong-clean-up
https://www.nationthailand.com/in-focus/30403710
Tim Russell did a great piece on cleaning up the waterways for TerraCycle Thai Foundation
https://www.timrussellphotography.asia/cleaning-bangkok-canals/
As well as for Khiri Travel in a podcast!
https://khiri.com/khiri-pulse/cleaning-the-canals/
One Bangkok Khlong that has been amazingly cleaned up is Ong Ang of which I posted earlier this year:
https://www.art58koen.net/single-post/ong-ang-past-present
And recently I cycled through a khlong side community in my area:
https://www.art58koen.net/single-post/riding-along-the-khlong