For some reason, my dupes, who seemed to have a way out, became trapped in an area with no oxygen. I tried to get them to build a ladder to air, but there were little to no resources available. I had them dig for some, they still wouldn't build or move.
Was also strange that there was a food shortage, but you can see in the screen shot an almost full food chest
Steps to Reproduce
Dupes partially standing in water? Nothing special... no background programs running except Steam
This issue has not been confirmed by a developer yet.