Do you mean "what should a better society do?" or "what would capitalist America do?"
For the former, my feeling is that the current homeowners can afford to take the loss. It's a wealthy town, and wealthy landowners can afford to go bankrupt.
I'm not American so I can't speak authoritatively for the latter; I suspect that the country that left Flint to deal with its water crisis on its own might not be as callous when it comes to the residential land investments of wealthier and Whiter people.