Wow, that's terrible. I wish I knew a place or some sort of oddjobs to help him out.
I understand it is state property and he was trespassing, but you would think someone would at least have the heart to leave a note on his tent, stating he had 2 days or so to pack up and move on. If he doesn't comply, go ahead and pack up his stuff, store it at the DOT for a month, if he doesn't claim it, then trash it. IMO that is how it should have been handled.
As far as his stuff being taken, around here we have dealt with the DOT removing signs we had put up for Church events because someone called and complained. We were able to call, and go pick up our signs at the DOT office without any trouble. The people at the DOT's advice on that subject, go put it back up, as long as it's not obstructing the view, we won't remove it until someone complains, then come pick it up and do it again. After about 2-3 times of doing this, I guess whoever had issues with it finally gave up. Not that this helps the situation, just stating that in some areas they do actually give some consideration to others.