I have a fortress on a mixed Haunted tundra/Wilderness Taiga map. It's freezing. There's no aquifer, so no water. We are working on melting a pool with magma to create a cistern, but because of the slow speed of magma it'll take a long time for the well to be usable. So, short story, no water. We do have alcohol.
In autumn of the third year I get a rash of dwarves dying of thirst. They weren't wounded. They just stopped drinking alcohol and worked until they died. "Give water" tasks were created, and some of my other dwarves fetched buckets, but to no avail obviously.
The first few deaths seemed to be people who'd been working close to magma recently, and the magma forges are really far from the food stockpile. I wondered when it began if people were just taking too long to get to the stockpile for refreshment, and created a secondary drinks-only stockpile near the forges. However, as with the other times I've done this, only empty barrels turned up there (drinks-only stockpiles seem buggy).
In any case, as people started dying in the Dining hall, I abandoned this theory.
The deaths spanned the strata of dwarven usefulness. My second-best engraver, a good miner, and a furnace operator who was being groomed as an armourer were among the victims. So were a baby, a child, a peasant and an unemployed cheesemaker. All told we lost about ten dwarves to this. A heavy blow to a fortress that only had 57 population when it started. The losses in skills were even more severe.
Creepily, the deaths began about the time the yearly Dwarven caravan turned up, and stopped when it left.
We've had one previous case of this the previous spring, I'd been very annoyed at the time, but thought the victim must have been wounded and I'd simply missed it. Not so now. None of the dead gave any indication of trouble prior to the death notice, and only two died in their bedrooms.
It was extremely frustrating to have dwarves die on me in a random and inexplicable fashion. I almost abandoned in frustration. I've played through winter and into the next spring, and there's been no more incidents. But I don't know what's causing it and when it'll happen again.
Anyone had anything like this before?