GSI Outdoors Water Cube

A cost- and weight-effective way to carry a lot of H2O, works well enough, but there is room for improvement.

A few days ago my wife and I ran into a not-so-little problem. We were on the road and had pulled out of a long-planned hiking trip in the Colorado Rockies due to a nasty weather forecast. So we decided to divert to Canyonlands and see if we could put together a nice hike there. We went online to check availability of backcountry campsites in the Needles sector of the NP and, it being prime time in canyon country, found that they were mostly booked up but there were a few available, so without further research or ado we booked ourselves into a three-night trip with mostly short days so there would be time for side trips.

Then we thought about water.

We called the NP and talked to a local in Moab and both said you can’t assume you’ll find good water out there—you should carry all you need, with the general recommendation of a gallon per person per day.

Ooops. That’s doable enough for a one nighter, but three? I suppose we could have modified our plans but we were both looking forward to getting away from cars and cell towers for three full days and our first day was only a couple miles in, so we decided to give it a shot. But how do you carry three full gallons of water in a 50L pack? Since we were originally planning on hiking in Colorado, not the desert, we had left all our spare water reservoirs at home, and so had just 3 and 2.5 liter bladders and a 1 liter bottle with us.

We could have spent a small fortune on more bladders at the Moab retailer, and we talked about somehow trying to fit supermarket gallon water jugs in our packs, but we looked around a bit more and stumbled across the GSI 10L water cube, at a very favorable price- and weight- to volume ratio. We bought two and figured we would make them work somehow.
Yep—these were all full when we set out, an estimated 26.5 kilos / 58.4 lbs of water

They worked, if not beautifully then quite well. Filled to capacity they slid right into our 50L Osprey Atmos/Aura packs, with a little room to stuff a few soft items around the sides.
You can do this.

They are one-piece molded out of low density polyethylene, which gives them some flexibility to mold around a water bladder and generally conform to the shape of the pack—more so after the first liter or so has been drawn out of them. They deflate as you use up the contents, and, except for the handle and spigot, they fold fairly flat when empty. 
They come with a hanging loop that is plenty strong enough for hanging 10 kilos of water from a tree branch.

Fill 'er up!

But there is room for improvement, at least from a backpacker's perspective. The valve and spigot work well enough, but the flow is a little slow so that squeezing helps speed things up. When hung from a tree the spigot hangs at an odd angle, easy enough to work with but it could be positioned better.

I also think the valve is vulnerable to damage or accidental opening in the pack or around the campsite, and can be a little awkward to pack around. I can envision something more like the valve on a wine box bladder, not recessed but a simple disk on the surface, but with a better flow capacity, and maybe a protective safety cover.

I’m not sure if the threads on the cap are compatible with gravity flow or other filter systems, but that would also be a good idea. They could also replace the molded handle with some kind of carrying loop that takes up a bit less space.

To be fair, GSI says that this item is good for “Car Camping, Destination Camping”—I’m not really sure what the latter is, but I don’t think they really had Gunga Din-type missions in mind. But I can heartily recommend these to anyone else who is foolhardy enough to head off into the desert for a multiday trip without knowing where the water is.

I haven’t yet verified the weight and volume, but according to GSI the 10 L water cube weighs in at 6 oz / 170 grams and will hold, of course, 10L / 2.6 gallons. I will edit this review when we get home to verify this. We paid $9.95 for each of the two that we bought.

P.S. The trip went well enough: tired legs and sore shoulders especially on day two, but beautiful scenery and nice campsites all the way. It was cool enough where our water demand while hiking wasn’t too high so that we actually had too much water and started luxury consuming (but not enough to bathe). As it turned out, there was treatable water here and there, but the Park Service couldn’t really verify where and how good so we took no chances. And we were walking on air on our last day, with only a couple of liters each.

Addendum, October 3rd 2017

The two that we bought both weigh in at 175 g = 6.17 oz. I filled one about as full as practical and estimated volume by the weight of the water, which turned out to be about 10.6 kg / liters. So the manufacturer's specs are pretty much on target.

I have also noticed that the eight corners of the cube get strongly creased when folding the cube flat, and because they are made of soft PE I think they could crack after repeated folding. I guess I can prevent this by not folding flat along the same lines every time, but even just rolling it up tends to crease the corners in the same way. I suppose there may be a tougher plastic for the job than LDPE, but that would probably jack the price up.

We may have a few more desert trips ahead and there's always car camping, so they may receive more use, we'll see how they hold up.