This... I actually would think it would be pretty cool to fill up jerry cans with water and leave them at your camp. Or you could go a step further and make it to where if you set an empty jerry can out in the rain then after a certain amount of time it will fill up with drinking water. Granted all of this would make us less dependent on drinking water, so to counter it I would make it so the only clean water you get is from collecting rain with jerry cans, and from pumps/wells. water from ponds and lakes would have to be boiled over a fire, or purified using tablets.