|This article is about an older version of DF.|
Dwarves, given time, will eventually get thirsty, as indicated by a blue down arrow blinking over the thirsty dwarf. If a dwarf fails to drink in time, the thirst will proceed to dehydration and eventually death. A dwarf needs to drink about once in three weeks.
A thirsty dwarf prefers to drink booze. If none is available, they will go to the nearest water source and drink. This is usually a well inside your fortress, but they will drink from a river or brook if there are no wells nearby, and have been observed to drink from murky pools if there are no other sources of water. A dwarf can live on water indefinitely if there is no booze to be had, but their speed and thus efficiency at work and in combat will suffer - dwarves are highly dependent on alcohol.
Dwarves seem to be capable of subsiding on vomit and slime in particularly dire times, though this is traumatizing and will quickly result in tantrums and insanity. This will usually only happen in cases of dwarves walling themselves in and being forgotten and in challenging embark locations.
A resting dwarf will not do anything on their own until they have recovered from recent injuries (preferably inside a hospital), and will depend on others to provide them with food and drink. They will not be given booze but receive water carried in buckets.