Regarding caching food,
I'd cache things like grits, oatmeal, rice, …, in soft drink bottles. This will hide the scent pretty good, are hard to chew through and are reusable.
Peanut butter and other hard plastic jars also work better than you typical food container.
Plastic bags, cookie tins, and many other containers can leak scent attracting critters.
Regarding water,
Those typical plastic gallon bottles that you get at supermarkets in the US will not last at all when exposed to cold, heat and especially UV.
Soft drink bottles are far more durable.
Supermarkets in the US often have inexpensive one and two liters of seltzer for cheap. The bottles are durable and can be reused. They don't seem to deteriorate under any conditions.
They are strong enough to hold up when buried under rocks.