Seems like a good opportunity to design and distribute plastic bags specifically for people poops (sort of like the bags for dog poops).
Also, fix the homeless problem. - https://imgs.xkcd.com/comics/tasks.png
For a variety of reasons - fear of government control, previous negative experience, fear of harassment or violence, conspiracies conjured up by someone with a mental condition - many homeless refuse "the system" and prefer the riverbank.
Hence "wealth distribution" problem, not "not having enough wealth" problem.