Back in the late Seventies some survivalist type came up with an idea for food and water storage in a PVC pipe. We just call them Bazooka's.
Just go to your local home improvement store and buy the largest diameter PCV pipe they sell 3 to 5 feet long, I normally use the six inch round tube. have it threaded on both ends. Take it home and figure out how many compartments you will need then cut six inch pieces of the thickest cardboard you can find, for as many compartments that you will need.
Seal one end of the pipe with an end cap, first use teflon tape to waterproof the seals.
Now figure out what your re-supply needs are. I have filled our Bazooka's with all kinds of stuff, food, water, those female hygiene things that have wings, clean clothes film ammo or any luxury items you may not want to carry. Separate each component with the cardboard circles, and seal the remaining cap waterproofing again.
Next we figure out which trail we project to be humping and use the weekends in between to plant our Bazooka's at various parts of the trail. If we enter a trailhead on the north end, we will spend a day or even a couple of nights seeding the south trailhead, you can also drive to the various towns along the trail some weekend and take a day hike to plant your Bazooka. The hiking and digging are good workouts in between trips. I try to dig my tube trench at least 16 to 18 inches deep to be below the frost line. I have had and currently have tubes I planted nearly two years ago NC SC GA. (the M.R.E can last five years or more in cool storage) They do not damage the environment, after digging up the tube you just fill the hole back in.
You might ask Pappy how do I find my Bazooka's at night. Well, fear not my friend aside from my map where they are planted, I break bike red reflectors into small pieces and drill a hole in them enough to drive a small tack nail through them, and tack them to the some of the trees we will be walking towards. I start at about a thousand yards from where I planted the tubes. My headlamp or flashlight will pick up the reflections, and I pull them out as I go.
I started using the Bazooka back in 95 during the start of the five year Carolina drought. In the Wharrie National Forest to store water as even in a good year its hard to find water in the Wharrie. If the water is older than three months iodine it first and re-aerate it by mixing it as old water can taste flat. It stays pretty cold if you keep it under the frost line. Have fun with it, they are easy to make and pack. Let the kids carry them, by the time they grow up they'll forget the hump anyway