Pretty much every prepper knows by now that water is one of the most essential resources in any survival situation. You can only go a couple of days without water before you die, and chances are you’ll be totally incapacitated well before that.
One of the most harrowing survival scenarios imaginable is being lost at sea or trapped on a deserted island. Surrounded by water, but none of its drinkable.
But, what if we boil ocean water like we would any other natural source of water? Would that somehow purified, make it safe to drink? Can you drink salt water if you boil it?
No, you cannot drink boiled salt water. Boiling salt water will only serve to concentrate the salt that it contains as the water evaporates, making it even saltier by volume and more harmful to drink.
It’s a nice thought, but boiling alone is just not going to get the job done if we want to make salt water into drinkable fresh water.
Boiling will actually kill the germs and other harmful microbes present in seawater, but that is the least of your worries if you’re trying to drink it.
The problem is solvable through distillation and desalinization, but the rest of the methods don’t work. Keep reading and I’ll tell you all about them…
What Happens if You Drink Seawater?
If you drink seawater, or any saltwater, you’ll only wind up more dehydrated. The kidneys simply cannot cope with the immense amount of salt, and fluid will be pulled from your cells by osmosis.
As a result, the body will try to compensate for the loss of water by releasing more urine, leading to further dehydration. This ends in hypernatremia: an abnormally high concentration of sodium in the blood.
The symptoms of hypernatremia, particularly from consumption of saltwater, will be severe and life-threatening. You will experience heart palpitations, dizziness, nausea, vomiting, and eventually seizures.
As the situation for your body grows more dire, you will experience brain swelling, organ shutdown, and cardiac arrest. If not reversed, drinking seawater will invariably lead to death.
How Long Can You Survive Drinking Seawater?
A person will survive no longer drinking seawater than they would if they had no water to drink, and they will likely dies even quicker than that. Seawater will cause dehydration to turn truly severe almost immediately, and death will soon follow.
Therefore, the only way to survive being lost at sea or trapped on a deserted island is to find a way of purifying salt water into drinkable fresh water as quickly as possible.
Does Boiling Seawater Remove Salt?
No. Boiling seawater does not remove salt from it, but that is good thinking. The net salt content remains the same regardless of whether the water is boiled or not, and in terms of concentration it actually makes water saltier: same salt content, less water, equals saltier water!
When seawater is boiled, the water evaporates, leaving behind the salt and other minerals that were dissolved in it.
However, boiling seawater can be a method to obtain freshwater from saltwater through a process called distillation. We’ll talk about that in just a little while…
Does Boiling Seawater Purify It?
Not truly, though it does help improve the quality of the seawater. Let me explain.
Boiling seawater will kill any germs and parasites present in it, making it safer to drink from a microbial perspective. However, boiling seawater doesn’t truly purify it, as it does not remove the salt in it.
Although boiling seawater can make it safer to drink microbially, it does not remove the salt, and so drinking this boiled ocean water will still lead to acute dehydration and hypernatremia.
So you might say in summary that boiling seawater can disinfect seawater, but it is not a true purification method.
Is Seawater Useable After Boiling?
For drinking, no, but seawater can be used for various purposes after boiling, even though it is not suitable for drinking.
You might use boiled seawater for cleaning purposes, such as cleaning dishes, tools, clothes, or other items, for instance, or any other application where better hygiene is important, but you aren’t ingesting it.
What Contaminants Does the Boiling of Seawater Remove?
Boiling seawater will eliminate most microorganisms, such as bacteria and viruses, present in it. It will also kill parasites, like protozoa, flatworms, and roundworms that may be found in the water.
Boiling seawater doesn’t eliminate chemical contaminants or heavy metals from the water. These substances require more advanced filtration processes to remove them from the water.
Therefore, boiling seawater is only effective for killing disease-causing organisms and making them safe to drink from a microbial perspective. It is not an effective way of purifying seawater into drinkable freshwater.
Can You Use Sterilization Tablets to Make Salt Water Safe?
Another nice try, and good thinking, but no. Sterilization tablets like chlorine or iodine are effective in killing bacteria and viruses in water, making it microbiologically safe to drink.
However, they cannot remove salt or other impurities from the water.
Also, any other method you might use to make seawater safe to drink will also necessarily purify it of germs and other nasty gribblies, so you don’t need to rely on steri-tabs in conjunction unless you’re forced to collect the purified water in a dirty container.
How Can You Make Seawater and Other Saltwater Safe to Drink?
Obtaining freshwater from seawater in a survival scenario is challenging, usually slow and sometimes laborious depending on what supplies and infrastructure you have access to.
However, there are two methods that can make seawater safe to drink reliably: distillation and desalination.
Distillation is a process that involves heating seawater to evaporate the water, leaving behind the salt and other impurities behind. The steam is then captured and allowed to condense back into liquid form, producing freshwater that is safe to drink.
The other method is desalination, a process that removes salt and other impurities from seawater typically by using powered technology.
Desalination technology is employed at the industrial level to supply water to many coastal cities, and at the smaller scale aboard ocean-going vessels of all sizes.
If all you want is a “countertop” model for home use, they are available and reasonably affordable, but you must have a way to power them. Obviously, your best bet in a legit, low-support or off-grid survival scenario is going to be distillation.
It is possible to set up a simple, and slow, improvised solar still with some plastic sheeting, a few containers, and some small stones and loose earth or sand.
But this is a skill you must practice and perfect before you are in the middle of a bad situation, and it takes time and effort to perfect the technique.
Obtaining freshwater from seawater is tough and slow, but it can be the difference between life and death in a saltwater-survival scenario, so you’d better make sure you can do it.
Tom Marlowe practically grew up with a gun in his hand, and has held all kinds of jobs in the gun industry: range safety, sales, instruction and consulting, Tom has the experience to help civilian shooters figure out what will work best for them.