I had a standard water well that was happily producing ~1300l/day for 3 years that suddenly went to zero. https://i.imgur.com/7ePiSsg.png
It was previously on a biiiig blue blob but that is now completely empty, like the groundwater has run dry!

At the time I was suffering a particularly harsh volcanic winter so I thought it might have something to do with the new icing mechanics freezing the well, so I enclosed and heated it for a few days but no change.

Is this a bug or feature? I have played with this mod for a long time and had no idea if this was a feature, but I also can't find any references to it elsewhere.