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You’re at the ocean. There is water. There is water everywhere but not a drop to drink. Or is there? Are there any ways to get potable water when you’re stuck somewhere near an ocean? Let’s explore the many possibilities, and one of these just might be the solution that you’ll need.


A growing number of anthropologists are of the belief that the oceans in the past were not barriers to human travel, but were the actual “highways” from which people traveled great distances. The well-charted currents can take a sail boat from the Mediterranean to the Caribbean, just as it did Columbus a few hundred years ago. And the path of the trade winds are not devoid of food, as you might think. Along the trade paths there are seaweeds, ocean birds, lots of fish, turtles – all the things that can sustain life on long voyages.

But what happens when your water supply runs out? Today, the well equipped sailor can phone or radio for help. But what if you’re out to sea unexpectedly, without adequate water. What can you do?

In the reports I’ve collected on sailors who survived when their ship floated out in the ocean, for 30 days or more, the survivors all have a few things in common.


One solution to diminishing fresh water is to mix your fresh water with ocean water. Thor Heyerdahl discovered his crew was able to mix up to 40 percent ocean water with 60 percent fresh water to extend their supplies. They experienced no ill effects, and noted this blend quenched the thirst better than straight water.

Other survivors reported they would drink ocean water, but only in little sips, little by little. Salty ocean water is not inherently poisonous, as is commonly believed. It contains sodium chloride, potassium chloride, and perhaps 20 more suspended minerals. If you were to drink it like regular water, the result is usually vomiting and diarrhea, and a net water loss. But slow sipping, never really enough at one time to quench the thirst, can be done if you discipline yourself. It has been done, and it might stave off dehydration.

Regular intake of fresh water is important, of course. But now your canteens and jugs are totally empty. What can you do?

If you planned ahead, you could set out your distillation device, fill it with ocean water, and suck out some potable water in a few hours.


A simple still can be made with two buckets and sheets of plastic. It’s not perfect, and it’s not highly efficient, but it will distill out drinkable water. The simplest version is to place one bucket into another, and put ocean water into the space between the buckets.You may have to put a rock or a weight into the inner bucket so it stays put. Then you cover this with a sheet of clear plastic, secure the plastic with a cord, and put a weight or rock in the middle of the plastic to create a cone shape in the middle. As the ocean water evaporates, pure water condenses on the bottom of the plastic and drips into the inner bucket. No, this is not perfect, and if you’re in a boat that’s constantly moving and rocking, you may not capture a lot of pure water in your inner bucket. Still, it’s worth trying if you have the supplies. But let’s assume you have no such device. What now?



Another possible source of water could be dew. By stretching and tying out a sheet of plastic, you could capture dew during the night. The sheet of plastic would need to be tied out, and have a slope that leads into a container. As the dew settles and coalesces, it drains into the container. Since this is wholly dependant on weather conditions, you might get a little and you might get a lot. There tends to be more dew during the nights when the daytime is clear.



It also rains out at sea, and again, if you stretch out a sheet of plastic, and slope it so that it drains into a bucket, you can capture rain water. In the field, I have collected a gallon in less than 15 minutes during a downpour. How much you can actually collect is determined by how hard it’s raining, and the size of your collection device (that is, the size of your sheet of plastic). There are not a lot of options for your water when you are stranded unexpectedly at sea. But survivors tell interesting tales, and though you might not hear all these options in your favorite glossy “survival manual,” these are some of the less likely ways to capture some palatable water.


Some, but not all, seaweeds, have flotation bubbles, usually at the base of the ”leaf.” These can be cut open and the liquid inside is typically less saline than the ocean. There is not a lot of water in each of these floats – maybe a half-teaspoon per float – but they could add up.


If you’ve managed to capture any of the animals who inhabit the sea for your meals, you might be surprised at the amount of liquid in their bodies. You can drain this out, strain it, and drink it. No, I didn’t say this was the best source of water, and I didn’t say you’d necessarily like it. But it is a source of needed liquid.


No, no, no! Urine is your body’s waste product. You could use urine to cool down, but why do that since you have the ocean all around? Urine is functional to treat chapped skin, but don’t ever drink it!


Let’s say you’ve beached up on some unknown shore. There are no towns or villages around where you can get some water or help. Where do you get your water? Are you in the South Pacific? Are there coconuts growing on your beach? Seriously, you can get a coconut, remove the outer husk, and using an awl-like device, cut into one of the three “eyes.” If your timing was right, you’ll have some sweet and nourishing water. If not, the coconut could be dry, or the water could be sour.


One way to obtain water from the beach areas is to simply dig a well above the high tide line. The beach will likely be very sandy and so it will be hard to dig a deep hole as the sand continually falls back into the hole. But keep at it, and dig deeper than the water level. Wait awhile for the water to clarify. This water is significantly less saline than the ocean water directly, and you may be able to obtain your needed water this way.


If you have a sheet of plastic, you can build a makeshift water still, exactly the same as desert travelers make. You dig a hole, maybe three feet deep and three feet across. Put a container in the middle. Cover the hole with a large sheet of clear plastic, and put a pebble in the middle so there is a down-ward pointing cone of plastic. Assuming it is sunny, the water in the soil will be constantly evaporating out into the atmosphere, except your plastic sheet will capture the condensation, and the cone-shape will cause the distilled water to drip back into your inner container. While you may not get all of your water this way, you should be able to get at least some of it through this method.

ASG-1502-Salt-06    ASG-1502-Salt-07

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Don’t forget that streams flow into the ocean. Explore around and look for springs and streams, whose water will not have to be distilled. By the way, distillation is a water purification method, so if the water you obtained was from one of the distillation methods, it is safe to drink. Otherwise, you might have to consider some method of purification. Just because you found a stream that flows into the ocean doesn’t mean you can drink it without reservation. The simplest method for purifying water of biological contaminants is boiling, which necessitates the ability to make a fire, and some sort of container – a discarded metal can will work fine.


These methods described cover the possibilities in most situations. But there may be other options too. The thing to keep in mind is that water is just about everywhere, and this is certainly true at the beach. The key is to find potable water, or find some method to make the ocean water drinkable. Don’t panic, stay calm, and don’t be afraid to experiment in your efforts to find a solution.

Is Salt Water Poisonous?

When we refer to ocean water as salt water, you would think we’re talking about water with sodium chloride. In fact, ocean water contains 20 or more suspended minerals. The toxic quality of ocean water has more to do with the way people have consumed it during emergencies, rather than its inherent quality. Rapid drinking and gulping in order to quench one’s thirst is often a culprit, since this way of consuming ocean water can lead to vomiting and a net loss of water.

On the other hand, virtually everyone who has survived a shipwreck or whose ship was stranded at sea consumes ocean water. These survivors disciplined themselves to sip — never gulp — the ocean water. Some survivors report mixing a majority of fresh water with some ocean water worked well to extend supplies.

SOLAR STILL – Cross Section


  1. Sheet of plastic, 5 to 6 ft. diameter. Soil around the edges holds the plastic in place. Note the condensation on the bottom of plastic.
    2. Smooth, egg-sized rock to form cone.
    3. Cup to catch water.
    4. Drinking tube, 1⁄4 inch diameter, approximately 5 feet long.
    5. Tube to allow urine in regularly without opening still. Note funnel at top.
    6. Broken cacti and other vegetation placed in hole.


Editors Note: A version of this article first appeared in the February 2015 print issue of American Survival Guide.