Backpacking is an excellent outdoor activity that has tons of benefits for the human body and mind.
However it is important to consider the impact that such activity causes on the environment. I always recommend taking the Awareness Course of the Leave No Trace organisation.

In every country most of the famous backpacking places also have regulations to preserve the environment. Those regulations are usually easy to follow and don't require specific equipment.

I recently went to a backpacking trip at El Pinacate and Gran Desierto de Altar Biosphere Reserve in Sonora, Mexico. This is a UNESCO World Heritage site. As it always should be the Leave No Trace rules apply and particularly about trash and human waste: it is forbidden to leave trash and it is not allowed to bury it, even if it is organic. This means: don't bury your poop!

So the big question is: how do you comfortably transport your human waste during a 3-days backpacking trip?

I did some research on the Internet and got inspired by the technique used for big wall climbing.

In this Instructable I will show you how to build my version of the human waste container that I called the Poop Tube.

During the design of this device, the main characteristics that I've been looking for are:

No odour escaping from the container
Easy to use
Compact
Lightweight
Inexpensive
Built using as much recycled material as possible

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Step 1: Material List

To build your own Poop Tube you will need:

One large plastic container with large mouth and air-tight lid. I choose to recycle a large pickles container (about 1gal) (restaurants throw them away).
One black plastic bag: a groceries bag is perfect!
One roll of biodegradable toilet paper. You can take the length you think necessary to reduce volume and weight.
Small size trash bags. The quantity depends on how many days you are going to travel, you are going to use one each time you will go to the toilet. The rule of thumb is one per day + two spares.
Medium size ziplock bags. You will need as many ziplock bags as trash bags.
Biodegradable laundry detergent.
Hygienic body wipes. Try to buy some environmental-friendly ones.

The detergent is used to reduce the odours, as the ziplock and the air-tight container.
The trash bags are needed to easily collect human waste.
The body wipes and toilet paper are there so you can keep good hygiene.
The groceries bag is used to hide (in the case you are using a transparent container) and extract easily everything.

Step 2: Build It

Each time and before you go backpacking you need to prepare your Poop Tube:

Insert two spoons of detergent in each ziplock bag.
Close tight the ziplock bag removing the air as much as possible.
Put all the ziplock bags and the trash bags in the groceries bag.
Stuff the groceries bag into the container.
Insert the toilet paper in the container and, when possible, the wipes too.
Close tight the container lid.
Write your name or a distinctive sign on the lid.

If you are planning to transport your Poop Tube outside of your backpack I suggest you stick a rope loop with duct tape to the container so you can hang it with a carabiner for example. Don't make holes on the lid or the container as you will lose the odour-tightness of it.

The name/sign on the lid is there so you won't use someone else's Poop Tube ... nobody would want that ;)

Step 3: How to Use It During Your Backpacking Trip

To use your Poop Tube follow the steps:

Find a flat and hidden spot.
Open the container and extract the wipes, the toilet paper and the groceries bag.
Take one trash bag, open it and flatten it wide open on the ground. Use small stones to maintain it there so the wind won't blow it away.
Do your thing aiming at the center of the trash bag.
Clean yourself and leave the used toilet paper and wipes in the trash bag.
Close the trash bag: bring up the neck that was flattened on the ground, make a knot trying to pack as less air as possible.
Insert the trash bag inside one ziplock bag and zip it tight trying to remove as much air as you can.
Put the ziplock bag in the groceries bag. At this stage the ziplock should not leak because of its tightness and the detergent absorbing the fluids.
Stuff back the groceries bag into the container.
Put the unused material on top of it.
Put back the paper roll and the wipes in the container.
Close the container tightly.

If you follow those steps you shouldn't get your hands dirty, if you do: use the wipes and water and soap to wash them.
No odour should get out of the container as long as it is kept closed.
The body waste can be seen by transparency in the ziplock bags but this shouldn't be possible once it's inside the opaque groceries bag and/or container.

Step 4: How to Dispose the Waste Once You Get Back From Your Trip

Simply extract the groceries bag from the container, remove the spare material (unused ziplock bags and trash bags), and throw it in a designated garbage.

Due to the tenacious odour of the body waste, the spare material get smelly, think about putting it back in the container and close it tightly.

Step 5: Conclusion

Now you know a way to preserve a protected environment from your body waste.

This is not the most ecological way to dispose body waste, because of all the plastic, detergent, paper and wipes used. However this is necessary in some places you go.
Don't use the Poop Tube if you can leave your body waste in a more appropriate way!

I suggest you to read the book How to shit in the woods written by Kathleen Meyer.

Feel free to comment and suggest corrections and enhancements!

Thank you for reading.