Welcome Preppers and Survivalists,
It is very important for preppers to store water, but sooner or later your family's stored water will run out, so you will need to collect water.
There are many methods of collecting water for your family to use. One of the easiest ways is to collect rainwater. In most cases, rainwater is ready to drink.
One way of collecting rainwater is to use a blue trap. Now, you don't have to use a blue tarp; you can use a sheet of plastic or a poncho to collect the rainwater.
To build, sink the four posts into the ground. You need to make sure the posts go in pretty deep. The posts and the string will have to hold the weight of the rainwater and also survive any wind gusts.
Next, tie the two high corners to the post with strong string. I used 550 cord. You don't need to use 550 cord; any strong string will work. After that, tie the tarp's two lower corners to the posts. Notice I tried to form a 'V' at the bottom. The 'V' directs the water into the bucket.
If you don't have a bucket, place the posts closer together and make all four corners the same height. The tarp will hold the water until you can empty it. Make sure you use strong string because a gallon of water weighs 8 pounds (4 liters weigh about 3.6 kilos)
You don't need four poles; you just need four places close enough together to tie the string to hold the tarp up. I have used trees (watch out for leaves and sticks), a fence and two poles, and ... your imagination.
As I wrote in the article, you can use a poncho, sheet of plastic, metal roofing, or anything that can be cleaned enough to collect water. Be reasonable with your imagination; you don't want to use anything dangerous that will leech chemicals into you collected water.
Kiddie pools, food-grade 5-gallon buckets, a hole lined with another tarp are some of the things that could be substituted for a bucket. Heck, if you don't mind getting wet, you could fill individual canteens as the water flows down the poncho.
550 cord, shoe laces, an electric cord from a lamp are some substitutions. If you use wooden poles, you could use nails to hold the tarp to the poles.
Lastly, if your plastic sheet or tarp doesn't have holes along the edges (grommets), you will have to use a technique I learned from M4040's "Tarp Shelter" page.
Yes, I know; I used a bed sheet for my explanation but it works for plastic sheeting, too.
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