My father manages a trade association for title insurance companies (the
American Land Title Association). I asked him what he had to say about this, given as much info as could be gathered from your post, and here's his reply, whether it helps or not:
I gather from his post that this is some kind of condemnation procedure exercised by either the local county/city government or one of thousands of quasi-governmental bodies set up to provide public services but vested with condemnation powers. Presumably, the homeowners cannot have their land taken without "just compensation," which may not truly compensate them for the loss they suffer but is intended to quantify it ($) and get on with the construction. It's important to remember that significant public improvements, particularly in already-developed areas, can't proceed if they require every impacted homeowner to agree with everything done--particurarly if what's being done benefits others but not the impacted homeowners! That's why eminent domain (condemnation) is in every state constitution.
The only way they might not be recompensed is if all this is done pursuant to an outstanding easement which is part of their title already. In that case, all those trees are just gone, period. Just like the disruption to our lawn by Cox this summer. Nothing we could do about that either--although politically we can complain loudly and local politicians might put some pressure, etc. on Cox. Probably not the case here.