Water Purification Methods at Home

The quality of your drinking water can be compromised at any time due to many reasons. Even if you’re no Bear Grylls, it’s always helpful to have some quick water-cleaning solutions in your arsenal to tackle potential nasty pollutants.

You can remove germs and impurities using any one of dozens of DIY methods, and I’ll share them all with you in this article. You can perform them right in your kitchen using ingredients and tools available at home, with minimal effort and money.

But here’s a little disclaimer: Such methods can only do so much to purify water and you ultimately need to invest in a proper purification system to get rid of the bad stuff permanently.

Let’s get into it.

Why Does Your Water Get Contaminated?

As you may well remember from your chemistry classes, water is a universal solvent. This means it can easily dissolve a wide variety of foreign particles—also known as pollutants.

Drinking water can catch pollutants from dirty or broken pipelines, surface runoff, sewer overflow, excessive rain, floods, the use of fertilizers and pesticides in a nearby farm, and unmindful waste disposal. Even after treatment in local plants, there’s no guarantee that your water is entirely devoid of harmful impurities. It can dissolve dirt, chemicals, and mineral sediment in the pipeline or through cracks and crevices into your water.

In some regions, the groundwater is naturally contaminated with a range of minerals and salts that can get into your drinking water and cause health hazards. Other times the problem is within your plumbing system or a malfunctioning water heater or water softener.

Whether you own a private well or get your water supplied by the public water system, it’s imperative to get it tested at least once in a year, as recommended by the US EPA.

I suggest you buy a water testing kit—if you don’t have one already—and use it once in a while to test for any change in the mineral makeup of your water. A testing kit will also come in handy when your water suddenly starts tasting and smelling bad.

You could also get your water tested in an accredited laboratory for around $100, but you’ll need to wait a few days for the results.

DIY Methods to Purify Water at Home

In a water emergency, the first thing you need to do is find an alternative source of healthy drinking water.

You can buy expensive bottled water from the market or ask your neighbors for help, but sometimes you may need an even quicker solution, and that’s where your DIY skills will come into play.

In extreme cases, you can also use these techniques to catch and clean water from rainfall, rivers, or lakes. If you’re a frequent wilderness adventurer, you might already be familiar with some of these tricks.

Basic filtration

The most basic water purification method is sieving water through a semipermeable or porous medium. You can use many everyday items as filter material for your water. 

Because this method actually removes pieces of stuff, some of which are large enough to see, basic filtration should be your first step before proceeding to disinfecting, boiling, or distilling water to remove smaller pollutants.

Some materials you can use to filter water include a coffee filter, cotton wool, clean cloth, paper towels, a sponge, small chips, grass, clay, sand, gravel, and rocks.

There are many ways to perform this filtration. The easiest method is to pass dirty water through the filter material and let it drop into a clean container. Here’s how:

  • Cut a plastic bottle in half and punch a small hole in the center of the bottle cap.
  • Place the upper part of the cut bottle—the neck of the bottle—upside down onto the lower part.
  • Now, fill this funnel with your preferred filter media and pour in water.
  • The clean water will slowly trickle down in the bottom container.

Keep in mind that this is not so much a method of purifying water as it is for removing sediment and similar materials. To make water safe to drink you must also try one of the following methods.

Boiling water

Boiling water is the easiest method for cleaning out bacteria, viruses, protozoa, and other disease-causing microbes from tap water. The heat denatures and destroys the structural components of microorganisms, making them inactive and harmless.

But keep in mind, boiling cannot remove other contaminants, such as minerals, chlorine, hydrogen sulfide, metallic ions, radioactive compounds, and chemical pollutants. In fact, boiling will increase the concentration of these contaminants in your pan as the water evaporates.

Only boil water if you’re sure it contains no other fatal pollutants.

Follow this simple procedure laid down by the Centers for Disease Control and Prevention (CDC):

  • If your water is cloudy, let it rest for 1–2 hours, so the solid pollutants settle at the bottom. Filter water to clean out any solid particles using the basic filtration method above. Again, you can use a coffee filter, a cloth, or a towel.
  • Put the filtered water in a pan or pot on the stove, bring it to a boil, and let it simmer for at least 60 seconds. If you are at a higher altitude, say 6,500 feet above sea level, boil your water for 3–4 minutes.
  • Let it cool in the air or, if you’re in a hurry, put it in the refrigerator.
  • Store the filtered water in a clean bottle or container.

If this water is too bland, you can add a little flavor by squeezing half a lemon into it or mixing in a pinch of salt.

Distillation

Distillation is hands down the surest way to remove all kinds of contaminants from your water at home. In this process, you vaporize water and condense it back into liquid, removing all the impurities that have a higher boiling point than water. One major downside is that it takes about 13 hours to produce one gallon of drinkable water.

Nonetheless, it’s a great way to make your water drinkable if it has impurities like arsenic, fluoride, chlorine, and microbes.

All you need is a big pan with a lid, a small bowl, and some ice cubes. You can even turn this into a fun family project to do with the kids.

  • Take a big pot and fill it with water. Now put a smaller bowl in the center of it. Don’t worry if the smaller bowl is floating at this point. You just have to make sure that there’s enough space above the big pot and around the small bowl for vapors to form.
  • Now turn on the stove and keep the heat at medium to medium-high. Bring your water to a simmer.
  • Use a lid that is slightly higher in the middle, and close the big pot by putting this lid upside down. This way, the vapor will collect at one spot in the center and fall into the smaller bowl.
  • To speed up the process, place ice cubes over the lid.
  • Distilled water will slowly collect in the smaller bowl, and you can refrigerate it or cool it naturally before storing it in a clean container.

If distilled water is too flat for your taste, add mineral drops, lemon juice, or salt.

Disinfection

Another widely used method to kill pathogens, bacteria, and viruses in dirty water is using liquid disinfectant chemicals. These are also easily available in the form of water purification tablets.

According to the CDC, most disinfectants are unable to kill stubborn pathogens like cryptosporidium and giardia. But it’s still a popular method of getting rid of microbes in water.

You should know that disinfecting will not remove minerals, metals, and other inorganic pollutants from water. For it to be effective, make sure the water is not cloudy or saturated with dirt and debris. 

You can use NSF-approved household bleach (5%–9% sodium hypochlorite), store-bought pool chlorine (about 12% sodium hypochlorite), hydrogen peroxide, and iodine. This method is convenient because you can disinfect a large amount of water quickly by adding the appropriate amount of chemicals to your storage tank or well.

Household bleach

Before using bleach, don’t forget to check the label on the bottle. Only use unscented household bleach that doesn’t contain any added chemicals. According to the EPA, mix two drops of bleach (6% or 8.25%) in a liter of water. Let it rest for 30 minutes before drinking it.

If you’re planning on disinfecting a large amount of water at once, the general rule of thumb is to add one gallon of household bleach in 1,000 gallons of water.

Chlorine 

If you’re using pool chlorine, add two teaspoons (~0.3 ounces) of chlorine in a liter of water. Or ½ gallon of it in 1,000 gallons of water. 

Iodine

And if you’re using liquid iodine, add five drops of 2% iodine in one liter of warm water (~68°F), mix well, and let it rest for 30 mins before consuming. In case you cannot warm up the water before treatment, mix the same amount of iodine, but let it rest for 45 minutes.

Hydrogen peroxide

Hydrogen peroxide is a weak disinfectant, but it’s widely used to treat iron bacteria and sulfur odors and doesn’t leave toxin by-products in the water. I suggest you go for a 3% or 7% concentration because it’s easier and safer to work with.

Using liquid disinfectants can be a little daunting because there are different types of chlorine bleach available in varying concentrations on the market. It’s very confusing for someone trying this method for the first time. Before heading to the store, it’s better to consult an expert or search the internet for proper calculations

Disinfection tablets

If you’re uncomfortable with liquid disinfectants, go for chlorine dioxide or iodine tablets and follow the instructions on the package.

UV flashlight

UV flashlight is an excellent way of removing bacteria, viruses, and protozoa in water. However, like the disinfection process, low-power UV lights are ineffective against cryptosporidium and giardia. 

Make sure you buy a UV flashlight designed to kill these microorganisms. A UV radiation of 254 nm (nanometers) in these lights damages the structure of microbes in water.

This is how you use a UV light to zap any microbes in your water:

  • Filter your water first to remove any solid particles.
  • Dip the light element in your water and stir for a minute. It normally takes 10 seconds for UV light to kill bacteria but to be sure no microbes are left in the water, you can swish the rod around for fifty more seconds. 

This method does not require any resting time; you can chug down the treated water right away. 

Solar disinfection

You only need sunlight for this water purification process. Yes, you read it right. SOLDIS or SODIS—short for solar disinfection—uses UV radiation and heat from the sunlight to treat microbial contamination. As you may have guessed, it is only efficient in sunny weather. Plus, there’s no guarantee that it will kill all the microbes in your water. SODIS is ineffective against other impurities, like metals and chemicals in water.

To perform SODIS, fill a small transparent bottle (not more than two liters) with dirty water and place it under direct sunlight for a day. In cloudy weather, leave the bottle for two consecutive days. 

One major catch, though: If you’re using a PET bottle, heating it up can leach harmful phthalates and Bisphenol A (BPA) into your water. These are toxic to the body, so use glass bottles instead to steer clear of these toxins. 

Cilantro

If your water is contaminated with heavy metals, cilantro can rescue you. Yes, the herb that everyone likes in their salsa, known internationally as coriander, has the ability to absorb metals like lead and nickel from water.

Cilantro can be applied to contaminated water in the following ways:

  • Fill a tube with cilantro and let water pass through.
  • Crush the dried cilantro, put it into tea bags, and place them in a water jug, water bottle, or pitcher for a few minutes.
  • Take a few stems and leaves of fresh cilantro, soak them in water for a couple of hours, and sieve the water.

Pine tree method 

This one is especially useful if you’re on a camping trip and are running out of clean water. The pine tree has good filtering properties and can be used to remove E. coli from water. Pine tree wood is made up of a porous xylem structure that is able to capture the pollutants in water. However, the pores in its network are not small enough to remove viruses.

This is how you use the pine tree method:

  • Cut a pine branch and peel it clean. Place the piece inside a pipe and fasten it. Now run water through the pipe or plug it into a tap.
  • You can also place a pine branch in a cup and let water run through it.

Portable filters

If your water gets contaminated often, invest in portable water filters, such as filter straws, bottles, pitchers, gravity-fed filters, distillers, and countertop reverse-osmosis systems. These units are budget friendly and can be placed anywhere in the house.

Effectiveness of DIY Methods to Treat Drinking Water

DIY methods of water purification are beneficial only to a certain extent. Although they can be adopted in times of emergency, their effectiveness depends on the types of contaminants you have in your water.

Some of these methods are only good for removing off-putting odors and tastes in water. While others can help remove heavy metals. You might need to perform more than one method to achieve the desired level of purification.

Distillation and reverse osmosis are the only processes that can remove all kinds of organic or chemical contaminants from water. They are two of several popular types of filtration systems.

Installing Purification Water Filters 

There is no better way to remove contaminants in your water supply than to invest in high-quality water purification systems. These systems are available in many designs and shapes and can be placed near the main water supply (point of entry) or at faucets and taps (point of use). Whole-house filters also protect your appliances and plumbing system from clogging and corrosion.

Here are some ways to purify water using proper at-home filtration units.

Activated-carbon filtration

Granular activated carbon or carbon blocks are a great way to remove pollutants such as free chlorine, volatile organic compounds, smoke, and dirt—particles greater than 0.3 microns. Some advanced carbon filters can also reduce the amount of lead and fluoride.

However, carbon filters cannot remove bacteria and viruses in water. If you’re installing one, you better combine this unit with other filters that can remove microbes and heavy metals.

These will cost you around $500.

Ion-exchange filters

If your test reports indicate high amounts of calcium and magnesium, get yourself an ion-exchange unit. Some ion-exchange devices can also replace lead, mercury, nitrates, and arsenic with sodium and potassium. They will cost you around $700.

Air-injection oxidizing (AIO) filters

AIO filters work by injecting oxygen in the water to oxidize metallic ions and turning them into solid removable particles. The particles are later mechanically filtered out by an inbuilt filter. AIO filters are a great way of removing iron and manganese from water. Advanced units use a periodic backwash system to flush all the impurities down the drain. They are available within the price range of $200–$1500.

Reverse-osmosis (RO) system

A whole-house reverse-osmosis system is slightly expensive but can remove all kinds of contaminants from water. It uses a semipermeable membrane with pore sizes as small as 0.001 microns that can capture bacteria, viruses, organic and inorganic compounds, and heavy metals. They don’t require regular maintenance or frequent filter replacements.

If you’re on a budget, you can go for point-of-use reverse-osmosis devices—available for as low as $200—that can be installed under the sink or placed on the counter.

Final Thoughts

At times, the clean water supply can be suddenly disrupted or you may face untimely water shutoffs due to a major maintenance in town or a natural disaster. In such dire situations, you can always use DIY methods at home to clean your drinking water.

All these methods are good for removing specific types of contaminants, so you might need to perform more than one method to clean out all the impurities. Moreover, what method you select highly depends on your water quality goals as well as the level of effort and time you can put into purifying water.

For a permanent solution, I suggest you go for full-fledged purification units, such as reverse osmose, activated carbon, or ion exchange, that can effectively remove a wide variety of contaminants. And in the meantime, I hope you have no need for these emergency solutions, but you’ll be glad you read this if you do.