Fuel Cache

[nickt]

I've never needed a fuel cache before and I'm wondering if you've any tips on leaving fuel/water cache for my bike in Mauri.

I'm assuming that I'll drive out in the 110 a few months before and leave fuel and water at a waypointed and remote location. I plan to use metal jerries for fuel and plastic for water. Obviously, I hit "mark" on the GPS where I dig the hole! How deep do you reckon? I think 8-12 inches of sand above the top will be more than enough to prevent any bad weather moving that much sand in a few months.

Any other tips?

Cheers,
Nick.

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Nick Taylor
www.exerro.com
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Vehicle Specs

[LuckyStriker]

I don’t know why I’m replying since I have no answer for you – Its just such an interesting post that I had to add my name to this thread!!

How many months prior? Won’t the water get stale and corrupted with microscopic larvae after a prolonged period?
A large volume of fuel (20l) should be fine for a few months if sealed adequately. Thereafter it turns into snot or evaporates.

I wouldn’t bury it too deep if I were you – GPS positioning suffers greatly due to weather conditions and other factors. Accuracy can be out by as much as 5meters. You could be digging holes for an entire day!
Perhaps you should bury a second cache about a mile away in case one is discovered. Sand can be weird – it will either lie still for millennia or tons of it can shift during a single storm…(not a sand expert – saw it on discovery channel) I guess you have to check if the sand you bury it in is old and stable (shallow hole) or fresh and dynamic (deep hole). But you knew this already…

I love my GPS but realise that the US Dep. of Def. can switch it off in a second, leaving me high and dry if I don’t have alternative means of navigation. If this works, can we call you ‘San’ or ‘Bushman’ from then on?

Very hard-core

[htdb33]

Be very cautious about this sort of thing. Your planning MUST include what to do if the cache is gone when you get there. I've had this happen to me and ended up on very short rations for a few day. However food is not such a big deal, no fuel or water could kill you. The suggesion for multiple sites is a good. Be sure to hide it well, however a savy local will most likely notice it despite of your efforts if he happens by the area.

Do not count on just your GPS to find your supplies when you come back. It will get you back to the general area, but you could end up doing a lot of digging if you dont know exactly where you left them. I would suggest some written instruction based off a prominent landmark in the vicinity. Compass bearing, pace count that sort of thing. Think buired pirate treasure.

Good luck,

Yankee Dog

[Chris Scott]

"Compass bearing, pace count that sort of thing. Think buired pirate treasure."

In my experience that is not good enough in the Sahara. On the open plain you may not find it, though I agree relying solely on GPS is a big mistake.
I was with a guy who, out of curiosity rather than need, tried to locate some of his old stuff in this way a couple of years after - off one of the trans-Tenere balises (flat all around) without luck. X paces off the post we could not dig up anything.

Far better to simply go off piste and put it right next to a distinctive feature like some rocks (not a distant landmark) which you can locate from memory (get a photo).and maybe plonk a rock on top as a marker - not with pacing around, macro GPS, cross bearings or back up dumps.

This worked for us - no GPS needed (apart from getting there by another route) Like htdb says, "Your planning MUST include what to do if the cache is gone...". We took care that our most remote dump was on or before our PNR, so we could ride back if it went wrong..

Actually burying it is not that important if you are confident it is far enough off the beaten track (near nomads, we hid one unburied cache at night). But Mauritania has more nomad activity than most of our places (and burying - or northfacing - will also stop it getting sun baked)

Water, food and fuel lasted fine over 3 (winter) months

CS

[htdb33]

Originally posted by Chris Scott:

Far better to simply go off piste and put it right next to a distinctive feature like some rocks (not a distant landmark) which you can locate from memory (get a photo).and maybe plonk a rock on top as a marker - not with pacing around, macro GPS, cross bearings or back up dumps.

I wont argue with this. When I said landmark I didnt mean distant, just one that would be easy to find later. And the pace count shouldn't add up to more than 5 or 10. I would certainly agree that 1 is even better but sometimes the condition of the soil may prevent that.

I wouldnt however count on locating anything from memory, at least not mine. A drawing or photo or both is your best bet. The rock on top is a good bet, just dont make is so obvious that it makes the locals curious.

yankee dog

[Roman]

Hello all,

This discussion touches on an interesting issue: is the general distrust in GPS's accuracy and usefulness backed by a body of evidence and real life experience(the more recent, the more relevant, of course), or is it an expresion of the "old school" approach, of the "too early to say" sort?

[htdb33]

I wouldnt say that I distrust the accuracy of a GPS. Its just that for this application they are just not accurate enough. On a good day the best I believe they are capable of is 3 meter accuracy. On a bad day 100. Both of these are generally good enough to get me where I am going on a trip.

The problem is that when you are looking for a cache, a circle with a 3 meter radius is a lot of dirt to dig up. Combined with a possible 3 meter error when you installed the cache and you could really be in for a lot of work.

yankee dog

[Roman]

Originally posted by htdb33:

...a circle with a 3 meter radius is a lot of dirt to dig up. Combined with a possible 3 meter error when you installed the cache and you could really be in for a lot of work.

Hello,

Maybe a simple metal detector would solve this problem? ;-)

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Roman (UK)
www.overlandcruiser.info

[Chris Scott]

.. or a bigger fuel tank ;-)

[Runner]

Ive been using caches of food, water, kit and firewood for the last 4 years in the Egyptian and Jordanian deserts and the key is a landmark - usually a big rock. Sand moves and GPS just isnt accurate enough. Ive never left water for more than two months and always used long life food (Army ration packs) so cant comment on how long they last etc.

Plot the landmark on the GPS and then go from there - either keep a 'Dump Book' in the way the old LRDG did, with a list of 'what is where' (which is what we have ended up doing) - with this idea you can keep updated lists of what you add or take from caches, or makes notes or descriptive names on each GPS point.

[nickt]

Thanks, lots of good info there.

If the LRDG were doing it, it's probably smart. I'll do a bit of a recce first, after all, I'll be in the 110 and see how it goes.

I'll let you know how, but not where, I get on!

Cheers,
Nick.

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Nick Taylor
www.exerro.com
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Vehicle Specs

[ctc]

Re storing water the UK plastic army surplus jerry cans are exceptionally watertight and its no accident that they are black - cuts out light and inhibits organic growth. You can also get large puritabs which do a whole jerry can.

I would also highlight a previous post which mentions locals locating your stash. I think this is highly probable if you are doing Atar to Nema route via Tidjikja.

Locals notice things which we just don't see.

[Sam Rutherford]

This is the way to do it, but could be considered overkill! You need two landmarks. Ideally several (many) kilometres apart. Stand at first one (bush (cut small notch out of a trunk for confirmation later/balise (scratch X)/big rock(scratch X)) etc. Take a piece of non-stretch string (50-100m long) and walk out towards your distant point (mountain-top). When you get to end of string, ensure that your string is taught, and makes the direct line to your mountain from your start point.

Decide on size of hole, and remove top-soil inch from that area (put in bag). Dig hole, putting dirt in second, larger, bag. Put stuff in hole, fill to almost level from big bag, then replace top-soil from little bag.

Chuck excess dirt away a few kms down the road as you are driving.

Come back X years later - with the same piece of string! (Or measure your string before-hand so that you can bring another piece if you have used it to make a hammock in the intervening period!). Make notes of your points - you'll be surprised how much different it will look when you return.

Take care to hide your footsteps outbound - locals will spot them, and then the freshly moved earth, otherwise.

[NeilT]

Don't think pirate think mountain rescue and avalanches! Stiff thin rod to poke into the sand to locate the stash before you need to start digging all over the place, might make GPS workable, let us know!

[gary -d90]

Hi there everyone

just joined this forum and this is the first thread i've checked out............

and very informative I have found it to be, so I would like to add my name to this thread & follow it with interest.

Regards, Gary