My glacier fort lived off nothing but cavern water for two years without a well, so as long as you designate a spot to be the drinky place, they'll go there.
Booze is the reason I like humans. They won't slowdown unless they're alcoholics, which I noted seems to be at a higher ratio among my soldiers, and as opposed to dwarves who need to be told where to drink if no well is available until nearly dead, humans readily go to the nearest source of water (if there's no river, they'll go to any old murky pool) for a drink.The only downside is they bitch about there not being a well and the water tasting like fly shit.
Dorfs on the other hand, as you know suffer that work slowdown.
So, a miner in glacialhell met his end in an accident today. Shame too. He was my best engraver and had the highest killcount. Long story short, I forgot to put in a support for my attempt to see if the ice cave in trick still worked. He landed headfirst. Good thing I have a bunch of fishery workers with no purpose to train up to replace him.
Seriously, if the guys from the caravan said "frozen wasteland" why the hell did all the fishery workers think that'd be a good place to move to? Hell most of them are basically waiting for enough hammers and maces to be made (I got a rediculous number of mace and hammerdorf veterans) so they can begin thier career change.