I had a reliable friend that happened to several times. Since then I have decided to be smart about it. If you check before you just jump in, or wade in and immediately STOP and LOOK you can see if it is a dead end or a real passage. At least with the circlet it is easy to see. If it is a dead end turn right around and get out. Not tried it with a torch but you should still be able to see.

tldr: Look before you leap. Always a good idea in this game. So many issues on this forum are cautionary tales of peeps that just aren't paying attention. Welcome to Valheim, a game that rewards the cautious and well prepared. Since that particular issue has been going on forever, it may well be on purpose and not a glitch at all. Who knows...