@PotomacBobI wonder what the English alternative for that would be, but in direct translation from Latvian, the ultimate drunkard would be our idiom of "to step/climb on a raft" or "to be/sit on a raft" with describe near-incoherent-state drunkenness that is maintained for a duration measured in days in a row, with acute or potential catastrophic consequences to one's work and/or social life. Or at least an acute drinking that has significant risk to develop into any such. But definitely not a general alcoholism as addiction if it's managed in way that not (yet) readily obvious.
I think even translated it's rather obvious as an idiom, describing drifting, being flushed downstream in an uncontrollable way.
Interestingly, the derivative from the above idiom use of the verb "rafting" as description of drinking in progress, points to the process of very heavy, unhinged drinking, but doesn't necessarily imply any duration for it.
Yes, this probably is a question.