When ever the government builds anything nice, it tends to stay that way because while people can add in to a mess that was already present their conscience does not allow them to be the first one to litter.
This would mean that if all the public places were clean, it would be able to stay that way with ease, the problem arises when people from a different place with dirty public places sees the clean place and get envious and ruin it.
The government also gives up eventually and that place also becomes a dystopian mess that would take a monumental effort to clean.