Water From Dirt

Water is always your most valuable resource; most people die from dehydration after three or four days without the stuff.

Although there are cases of people lasting at least a week without water—the crew of the downed plane Lady Be Good survived walking one hundred miles (160km) across the scorching Libyan desert for eight days with no water—it’s not a good idea to tempt fate.

If you’re pinched for water, you can always get it directly from the ground itself. Enter the solar still, an easy-to-make contraption that uses a tarp or a piece of plastic to collect evaporated water from dirt. All you need to do is dig a hole in direct sunlight and drape your tarp over the opening. Secure the edges with logs, rocks, boxes of tampons—anything you have lying around.

Then—and this is important—place a little pebble right in the middle of the tarp, so it pulls the plastic down into an upside-down pinnacle. 

When the sun hits the tarp, the air trapped inside the whole heats up, which in turn evaporates the moisture in the dirt. As that moisture rises, it will condense on the underside of the tarp and run down to the center—the lowest point. A cup or bowl on the floor of the whole right below this point will catch the pure, distilled water as it drips down—potentially saving your life.