My job is very stressful and morale is low. Management are in complete denial. I work in a niche department within a large company and there are only about 30 of us, and the staff satisfaction survey is only for our department. It is supposedly anonymous but once you've put in your location and other stuff etc it will be easy as anything to work out who's said what. For this reason I think a lot of my colleagues won't be honest. We all wory about reprisals. The departmental director is widely disliked and feared because he is a bully who has his favourites. And the survey has to be returned to him 
I am inclined to be completely honest (otherwise what is the point?), but hopefully in a constructive way, so rather than giving things a wholesale slagging off I am think of saying that more of x y z would be desirable etc. However it is going to be hard being completely honest without referring to individuals directly or indirectly because it is the behaviour of some individuals that makes the job so hard at times. Including the boss.
I am on holiday this week and it's really pissing me off how much this is getting to me.
Any advice appreciated.
PS I know I should be getting another job but not that easy in my line of work.