Learning how to filter water in the wild is a critical survival skill. Water often isn’t hard to come by when you’re out in the woods. In fact, it’s the most abundant resource on Earth. Unfortunately, only a tiny proportion of water you’ll find out in the wild is consumable. The best way to get drinkable water is to bring your own, but that’s not always feasible.
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Here are seven ways to purify water in the wild. Try these methods before you’re in a desperate situation so you can proceed confidently.
You could be at the river, a lake, a pond, or any body of water when you need to collect this resource. It’s essential for hydration, bathing, cooking, and more. The water may appear clean—sometimes, you can even see right to the bottom because it’s so clear. However, it could be contaminated with bacteria and viruses that can harm you quickly and lead to waterborne illnesses.
Waterborne illnesses are a significant problem in the United States, with over 7 million cases occurring annually. The diseases you encounter depend on where you travel, but the most common are:
There is a difference between filtering and purifying water, although their objectives are similar. Filtering includes draining the water through a device to remove bacteria and other debris. Filtration requires physical tools, so you’ll have to know how to make a water filter in the wild or bring water storage materials from home.
Purifying, on the other hand, uses chemicals or disinfecting methods to kill the bacteria and other organisms inside the water. Doing this will reduce the risk of becoming sick from contaminated water.
You may encounter waterborne illnesses from lakes or rivers. Drinking the water without cleaning it is risky, but water is at the top of the rule of three for survival. Now, obviously if you’re in danger of dying from dehydration, you’re better off taking your chances with unknown water sources than dying. However, if you become ill from a waterborne illness, you’ll be in much worse shape than you started if you don’t find help before then!
These seven methods can provide you and others with water, and you can even learn how to make a water filter in the wild.
The first water purification method on the list is boiling your water. Boiling is among the most practical ways to purify water. Most parasites and bacteria can’t survive in temperatures over 170 degrees Fahrenheit. Your water will boil at 212 degrees at sea level and about 200 degrees in high-elevation areas. It’s a safe bet in the wild if you have a campfire.
Boiling water is practical, but there are some drawbacks. You can figure out how to start a fire without matches, but ideally you’ll want a camping stove, which may be difficult to access. Additionally, boiling limits how much water you can purify at a time. The water you boil is hot, and it will take a while to cool down for drinking. However, boiled water is ideal for cooking. And, as a bonus, being able to cook your food makes it much easier to meet your minimum calories needs per day.
Another water purification method you can use is purifying drops. This approach requires less effort than boiling, and the drops or tablets are inexpensive. Many people use liquid iodine or iodine tablets to disinfect their water. You should be able to find them at drugstores or camping and outdoor suppliers.
You should be careful with this technique, though, because there are some risks involved. People who have a thyroid problem, are pregnant, or are sensitive to iodine shouldn’t consume this water.
Liquid iodine works best with warm water above 68 degrees Fahrenheit. If your water is warm, add five drops of iodine per liter. Mix and let it sit for at least 30 minutes. If your water is cold, you can still use iodine tablets; however, you should let the water sit with the iodine for at least 40 minutes. Cloudy water should get 10 drops to ensure your safety.
One downfall of iodine is that the water may taste unpleasant. You can add flavoring mixes like a powder, but you should wait at least 30 minutes after adding the iodine to ensure it’s effective.
Another option you have to filter your water in the wilderness is a filtering pump. You can bring one from home, as these devices are commonplace in outdoor stores. Pump water filters are one of the quickest ways to get drinkable water in the wild, and you’ll rarely find a long distance hiker without one.
There are two primary types you’ll find: pump-action and suction filters. The pump method requires you to pump the water through a filter manually into another container. The suction filter cleans the water as you suck it from a hose. Filtering pumps come in handy because of how quickly you can get clean water. They’re ideal for hydrating yourself, which is one of the essential survival rules.
Their practicality does come at a price—literally—because they can get expensive. Plus, you will have to take care of the filter when it clogs. Filtering a lot of water can also really wear you out, and the pumps can occupy a lot of space in your supply bags.
Filtering pumps may be unavailable in the wilderness. When push comes to shove, you’ll need to know how to make a water filter using materials from the earth, also known as primitive filtering. You can employ this method using soil or sand. Primitive filtering requires you to rinse the water through until it’s clear. The ground will filter the sediment in your water, but will have a hard time with bacteria.
Filtering water this way will be necessary if you’re desperate and have limited or no tools. But you should know that rather than rendering your water completely safe, this just lowers the likelihood that it will make you sick.
All you need is two containers, a shirt or other cloth, sand, and gravel. First, take a container and fill it with water. Lay your fabric on the other container, then place pebbles on the cloth. Pour water over your homemade filter, replace the rocks with sand, and pour the water again. The more and finer sand you pour through, the better off you’ll be.
Using solar power to disinfect water can be effective. All you need to do is fill up clear glass or plastic bottles with contaminated water and lay them out so they’re exposed to sunlight. The sun’s ultraviolet (UV) rays will kill the bacteria and viruses in your water.
The solar disinfection method is easy and inexpensive. You don’t need any tools and don’t have to tend to the water as it’s sitting there. However, there are some disadvantages.
This approach is not ideal if you need water quickly, because it takes at least a full day of sunny weather to disinfect properly. This method is also ineffective on rainy or cloudy days. It does take care of biological hazards in the water, but chemical contaminations may still be there. In addition, cloudy water is difficult to fully sanitize using UV rays. Other ways may be better for those learning how to filter water in the wild, but solar water purification can get the job done in desperate times.
Distilling is a safe method for treating your water in the wild, but can be difficult to pull off. Distillation is the process of purifying water through heating and cooling. It’s similar to boiling, but there are some distinctions. Distilling water removes impurities, such as microorganisms and minerals. Boiling will kill the organisms, but it still contains minerals. Distilled water, on the other hand, is about as pure as you can get water in the wild. The most common reason you’d need to distill your water instead of just boiling it is because it's how to desalinate salt water for survival. You can boil ocean water all you want, but the salt in it will still dehydrate and kill you.
Distilling water in the wilderness can be challenging, but there are ways to do it. You’ll need ways to boil the water, capture the steam, and let it cool down. You can use as few materials as two glass bottles, or you can use aluminum foil, a pot, and a glass jar.
As an example, let’s say you have a metal water bottle with you and you found some tubing of some sort (ideally metal). You’d fill your water bottle with saltwater and seal the tubing into the water bottle opening as tightly as possible. Then wet rags or seaweed or something similar and wrap it all over the tube. (This keeps the tubing cool.)
Next, start a fire under your metal bottle. The water will boil, forcing steam into the tubing. As the steam touches the cooler tubing, it will condense into water. You’ll angle that tubing downwards away from your water bottle. The condensed water will drip out of the tube and can be collected in another container. All the salt will be left behind, with only pure water turning into steam.
Gravity filters may be your best option for filtering water if you have a large group of people with you. You can process a lot of water with a short waiting time, and there’s no manual pumping or stirring required. As the name suggests, gravity filters pull water from its reservoir into the filter and then move the clean liquid into a container. The filter will stop particles and other unwanted materials from entering your drinking water.
Gravity filters are practical because they do the work for you. However, you will need a tree branch or a robust support system to hold them. These filters can be heavy, so this part is easier said than done, and often makes them more suitable to a long term
Remember, learning how to purify water in the wild is crucial for any outdoor enthusiast or survivalist. Waterborne illnesses can be severe, and in some cases, life-threatening. Therefore, it's essential to understand and practice different ways to filter water in the wild. Not only does this knowledge increase your chances of survival, but it also boosts your confidence when venturing out into the wilderness.
Water covers 72% of the Earth, making it the most abundant resource on the planet. However, only 3% is freshwater and just 1.2% is safe for humans to consume. In the wilderness, that 1% is hard to come across. You’ll be in a much better position if you know how to filter and purify water safely and effectively to remain healthy and hydrated.