Water is required to quench thirst and is utilized for many other activities, including hideworking, cooking and physician. It can be put in containers by pushing A (apply), select the container and F (fill) while standing next to a water tile.
An easy way to break through thick ice is to have enough animals standing on one tile, this always happens when you enter the terrain map. The animals/pets/companions will always stand on the tile east of you upon entering the terrain map, this is really convenient when you need to fish and especially when you need to retrieve your nets that are on frozen tile/s.
In some cases you will need to wait a few turns for animal/s to crack and finally break through the ice.
Type and quantity of animals needed to fall/break through thick ice:
1 Big Bull
Note: containers with water in them cannot be traded.Verify