Refillable canteens don't work for various reasons which i can drone on about for 5 paragraphs and have done already, so in the next update i have added water butts instead, which are like micro versions of the water towers which can be minified and taken on trips, the water is used during travel for hygiene and thirst if enabled, unless the tile has a high chance of containing water based on rainfall or rivers, and then it can be placed when you set up a camp and used like a well until it runs out, they can also be sold for a small profit based on how filled they are.