When most people think of a cache, they picture a piece of plastic sewer pipe, capped on each end, that has been buried in the ground. This option may work for some folks, in some locations, but is not the only way to set up a cache.
Remember, the word “cache” comes from the French verb “cacher”, which means “to hide”. Obviously a cache must be hidden, but what other things will you need to consider when thinking about hiding supplies?
Is the place you want to hide your supplies accessible year-round? Will snow or flooding cut off the routes to your cache? Weather is one of the reasons we prepare, so you'll need to take it into consideration when planning a cache. Mountain roads are hazardous in the winter even when maintained by government road crews, how do you think they'll be after TSHTF? Bridges are another possible problem, since a good portion of the bridges in the USA are old and in poor condition. Route planning is a separate issue, but something that needs to be looked at when planning a cache.
Who else has access to the location of your cache? Burying anything on public land leaves it vulnerable to discovery by anyone passing through the area. While using land that is not linked to you may have OPSEC (Operational Security) value, it lowers the chances of your being able to recover your cache intact.
Hollywood seems to like the idea of using a public storage unit for caching supplies- the theme pops up in several movies. While having a 10 x 15 space packed with emergency supplies sounds like a wonderful idea (if you can afford to fill it), it gets expensive to pay the monthly rent and you would have no control over the security of it. Most of the storage units that I have seen or helped empty were full of household items and didn't contain much of value, to the looting of public storage wouldn't be likely until well after TSHTF.
Caching things at a friend's place will provide some security and ease of recovery, but everyone in the friend's household as well as any guests will potentially have access to your supplies. Fire, theft, divorce, and other calamities could also destroy your supplies.
Can you retrieve or monitor your cache easily?
The first step in retrieving a cache is finding it. Do you remember exactly where you buried it? Did you draw a map (if you do, use a code or other way to encrypt the data) of its location? Landmarks change rapidly- buildings are torn down, trees are cut, fences are removed, bridges replaced or moved, etc. so you need to have several ways of locating your cache. Geo-caching as a hobby is a good way to practice locating a hidden cache, but you'll need encrypt your GPS coordinates in some manner to prevent others from finding it. GPS is satellite-based, and is subject to government shut-down in times of emergency, so learn how to read a topo map and get the maps that cover your areas.
I live in the upper Midwest, so I have to take climate into consideration any time I think about burying something. Around here the frost line goes down about three feet during an average winter. That means that the ground freezes solid for the first three feet of digging. A wet summer followed by a colder than normal winter can drive the frost four feet deep. Without the use of industrial excavating equipment, anything buried below the frost line is going to be a chore to recover. Anything buried in the frost zone will likely “float” to the surface as the frost comes and goes over a few years or get damaged from the pressure created by the freezing water. Frost heave is capable of lifting roads and cracking concrete, so a PVC pipe isn't going to withstand it.
What you put in your cache will have some bearing on where you hide it. Anything with a shelf-life will need to be rotated out so plan on retrieving and re-hiding your cache at scheduled times. In general, the more you mess with a cache the more likely it is to be discovered by someone else. Digging leaves disturbed soil that is easy for a trained/experienced person to spot. Visitors to remote areas are noticed by locals, whether the visitors know it or not. Frequent trips to a cache site will stir the curiosity of observers and may lead to the uncovering of your cache. The best bet would be to avoid anything with a shelf-life and never visit a cache site until you need the contents, but that would mean never being certain if it was intact until you needed it.
SizeA piece of PVC pipe will hold a few day's worth of food, basic shelter, some fire-starting tools, and maybe some clothing. Common sizes of PVC are from 8-14 inches in diameter, with the smaller ones being easier to transport to your hiding spot and much easier to dig a hole for. They are also harder to find when you try to retrieve your cache. One method of hiding PVC caches is to use the same size and color as your existing house plumbing to add on “extra” drains in your home. If you have access to your plumbing (not all hidden in walls or before the walls are finished) you could place a few “spare” drain lines that would pass a quick inspection. Not many burglars are going to be cracking open sewer lines looking for valuables, but government representatives might.
Plastic 55-gallon drums will hold a lot more than a piece of sewer pipe, but are harder to transport discretely and take considerable effort to hide successfully. Most plastic drums weigh about 25 pounds empty, so carrying one on your back as you trek into the forest to your cache site is going to be the first workout. Digging the hole will be the second, and carrying all of the contents will be the third. Something this size is a candidate for storage in a friend's basement or garage rather than burial.
These are the things that go through my head when considering a possible cache, and may or may not fit your local variables. Learning how to hide things is like learning any other art, it takes practice and planning. For OPSEC reasons, I will not ask for details about anyone elses cache sites or plans. This is a prepper site and I know there are unfriendly people who scan these sites looking for targets of opportunity (mostly wannabe warlords and couch commandos) so I won't feed them intel. If you have general ideas or suggestions that fit your location, feel free to leave a comment here or on our Facebook page.