What will it take?

[Oldfellah]

Its a difficult one really - go in too heavy handed & that's going to cause problems (no one wants to see a repeat of Red squad) but doing nothing very much isn't getting them to move.
They perhaps need an incentive - a week's worth of heavy rain & strong wind might do the trick, but that's unlikely to happen.

A months worth of stopping their dole and benefit might do something.