Did you know that one inch of rain falling over a 5-foot by 8-foot tarp would give you almost 25 gallons of rain water? And fresh rain water can be one of your best drinking sources during an emergency or after a disaster, so long as that disaster wasn’t nuclear or chemical.

All you’ll need to make the rain clouds work for you is a tarp, some rope and a large container, like a clean bucket. 

Tie up two adjacent corners of the tarp to trees or poles. Fix the other two tarp corners to the ground, so that there is a little sag in the middle of the tarp. Place your bucket under the lowest point in the tarp, and then pray for rain.

Providing it isn’t too windy, you could set up a rain collector for other projects besides survival. Use one to collect free water for gardens, fruit trees, livestock, or whatever. I always feel bad for my city friends with a water bill, and a matching sewer bill.

Here’s where the math kicks in to convince all you skeptics. The main reason that resourceful people have rain barrels at the bottom of their gutters is the fact that an inch of rain over one square foot will give you .622 gallons of water. That’s a lot of water from a small space. And whether it’s your roof, or an elaborate system of tarps that provide both shelter and water, you can use that number and a rain gauge to make a good guess about the amount of water that you could harvest.

Regardless of your home being urban or your campsite being remote, catching rain should be in your bag of tricks.