A small water purification system is one of the few real essentials for any traveler.  With access to safe drinking water often a daily issue, buying bottled water is not a sustainable solution. Economically and ecologically. Humanity already produces more than one million plastic bottles a minute. We can use smarter alternatives, starting at less than 25$.

Safe Tap Water

Tap water is perfectly safe to drink in many countries. According to the CDC, this includes the USA, Canada, Western Europe, Chile, Japan, South Korea, Singapore, Australia and New Zealand. In countries like Germany the quality of tap water even regularly exceeds the standards of the water bottling industry.

water spring
Water coming from a mountain spring deep in the Sinai mountains, Egypt
The CDC guidelines are very conservative. Tap water can still be safe to drink at least locally. In mountainous areas, water often comes from nearby pristine springs. Ask the locals. If there remains a doubt about the possible presence of pathogens, boil the water. Or use a filter, UV lamp, or chemical purification. If the taste is bad use an activated charcoal filter. If particles are an issue, consider microfiltration.

Local Safe Drinking Water Services

In countries where the tap water is unsafe to drink there are usually local purification services in place. This is also the only safe option in case of suspected chemical contamination.

Drinking water is usually obtained from larger filtration and reverse osmosis systems. For example, you will find dispensers all over India, free of charge. Often even in remote villages. Smaller systems are commonly used in many middle- and upper-class homes.

water purification reverse osmosis
A professional unit hiding under the sink to handle desalinated tap water in Saudi Arabia

Alternatively, affordable purified water is often sold in larger, reusable bottles. For example in Thailand. Typically they hold around 20 liters / 5 gallons and require a deposit. Once empty you simply exchange it at the shop for a full one. This solution makes a lot of sense if you are staying for more than a couple of days.

There is another thing to consider when drinking lots of reverse osmosis water. It is low in minerals and electrolytes. That can be problematic if you are sweating and drinking a lot. However, there is no need to buy commercial rehydration salts. Adjust your diet instead. Table salt is a good source of sodium and chloride. Dairy products and leafy greens cover your calcium needs. Nuts and seeds are an excellent source of magnesium. And fruits like bananas, avocados or coconut water provide the potassium.

Reusable Water Bottle:
Plastic & Metal

Carrying a reusable water bottle is the first step towards cutting on plastic waste. This can be as simple as refilling a normal plastic bottle a few times. For example, a humble PET bottle will not leak or break and can last for months. Plus finding an empty soda bottle is never an issue. The major limitation is that it cannot be used for hot drinks.

nalgene water bottle
The classic Nalgene bottle, ready for climbing

A more flexible and durable option is a lexan polycarbonate bottle. Think classic Nalgene. Such a bottle can last for many years, and carries anything from cold water to hot tea. Many companies have stopped using potentially harmful BPAs in the materials. However keep in mind that in many countries the industry doesn’t follow very strict standards.

If you want to avoid plastic completely stainless steel is another good option. Insulated models tend to be heavier and more expensive, but extremely durable. As a big plus, they will keep your drink cold or hot for hours.

Water Purification:

Description. The WHO considers bringing water to a rolling boil and letting it cool down sufficient to kill pathogens. In many countries such as Argentina and China free hot water dispensers are available publicly. Otherwise, a kettle is rarely far. The weight-conscious traveler can even consider bringing a small travel immersion heater.

water boiling hobo stove
You need next to nothing to improvise a hobo stove

Advantages. Exceedingly simple, cheap. You can get a hot drink almost anywhere on Earth. Boiling also evaporates most of the chlorine in tap water.

Disadvantages. If you prefer cold water you will have to be patient. Requires electricity or a heat source and a pot. Doesn’t address microplastic particle or chemical contamination.

Water Purification:
Carbon Filtering

Description. Carbon filtering uses activated charcoal to remove odors and residual taste. It can also remove some chemical contaminants. Small bottles with an integrated filter can be carried anywhere. Alternatively, you can add a small extra unit if you are using an inline or gravity filter. Filters need to be replaced every 100-300 liters (25-75 gallons) on average.

Advantages. Tap water is often perfectly safe to drink but has poor taste. Particularly when it is heavily chlorinated. If that’s the only problem then charcoal filtering is all you really need.

Disadvantages. Don’t believe the ads. Carbon filtering does not remove all chemical contaminants. Nor does it tackle micro-organisms and small particles unless you combine it with a microfilter. Moreover, the filters have a short lifespan. Therefore it makes it expensive and complicated to resupply.

Chemical Treatment:

Description. Iodine drops or tablets can kill most but not all pathogens commonly found in fresh water. Water has to be treated for 30-60 minutes. Typical shelf life is around 5 years. Certain commercial kits include a secondary treatment to remove the iodine taste.

Advantages. Treated water reduces by 98% the intake of radioactive iodine by the thyroid. But unless you expect nuclear fallout, this feature is of little use to the traveler (hopefully).

Disadvantages. Because of the better taste and superior efficacy, particularly against Cryptosporidium, chlorine dioxide tablets have become the preferred chemical water purification solution.

Chemical Treatment:

Description. Available as tablets or a two part solution. There are different chlorine compounds on the market. Chlorine dioxide the most efficient option. Especially if using murky water or if Cryptosporidium contamination is suspected. Recommended treatment time is around 30 minutes. Typical shelf life is between 4 and 5 years.

Advantages. Lightweight, compact and simple. It’s easy to always pack a few tablets in an emergency kit or at the bottom of a bag.

Shortcomings. Liquid chlorine solutions can spill more easily. Maximum efficiency against cysts such as Cryptosporidium is reached after 4 hours. Expensive and requires far too many tablets for daily consumption. If you suspect a contamination with microparticles you will need a filter. Does not remove chemical contamination.

Water Purification:
Ultra-Violet Light

Description. The SteriPEN has the monopoly in that cathegory. A small yet powerful battery-powered UV lamp kills pathogens in 90 seconds or less. There are different models available. But USB-rechargeable SteriPENs are the more convenient option for regular use. The typical unit has a lifespan of 8000L.

Advantages. Water purification is instantaneous, odorless and simple. Most importantly, it kills viruses. Just put the UV lamp in the water and stir. It even works in a glass of water at the restaurant. The SteriPEN is ideal for treating tap water rapidly.

Shortcomings. Water turbidity is the Achilles heel of the SteriPEN. If it’s cloudy the UV light can’t penetrate properly. If you go trekking you might have to use a filter first. Similarly, if you are worried about microplastic contamination you will need to add a filtration step. And then there is the power issue. If you don’t have access to at least a small solar panel every few days you are in trouble. Plus batteries don’t like the cold. Moreover, quite a few users have complained about early failures of the UV lamp. Finally, the SteriPEN does not remove chemical contamination.

Water Purification:

Description. There is a big selection of portable filters currently available on the market. Larger units use a manual pump or gravity and are ideal for groups. Smaller ones rely on suction or squeezing a bag. Filter sizes between 0.1 and 0.3 microns remove all bacteria and protozoa as well as microplastic particles. Lifespan varies a lot, between 150 and 350000 liters (25 and 100000 gallons).

gravity water filter
Gravity water filters are great for large volumes

Advantages. Fast water treatment and reliable, simple operation. Affordable. Most units can be field-maintained. This makes it by far the most popular water purification solution.

Shortcomings. Microfiltration, unlike ultrafiltration, is not small enough to filter all but the biggest viruses. The filter cartridges can be fragile, and often must be protected from bigger impacts and freezing temperatures. Dirty water requires frequent cleaning of the filter unit. Does not remove chemical contamination.

Water Purification:

Description. A few filters remove particles as small as 0.02 microns. This is effective against viruses on top of bacteria, protozoa and microparticles. Lifespan ranges from 1000 to 1000000 liters (260 to 260000 gallons).

sudan clay water jugs
Ultrafiltration is ideal for the ubiquitous clay water jars in Sudan

Advantages. The best long-term solution if viral contamination is an issue. Ideal for extended stays in developing countries.

Shortcomings. One way or another, it’s a compromise. The MSR Guardian is a small technological wonder but costs 350$. The Sawyer One Zero Two and the Lifestraw Mission are more affordable at 130$. But the flow rate is significantly slower than microfiltration systems. Does not remove chemical contamination.

Water Purification:
Hybrid Filtration

Description. There is a growing number of products combining microfiltration with other treatments, such as activated charcoal and ion-exchange membranes. The Grayl Ultralight and Sawyer S3 are convenient squeeze bottles. The Acquamira Frontier Max and RapidPure Pioneer are compact and relatively affordable (under 50$) inline filters.

Advantages. These all-in-one solutions remove pathogens, microparticles, some chemical contaminants and improve taste.

Shortcomings. The lifespan of filter cartridges is extremely short, at around 150 liters / 25 gallons. That means that you are forced to carry around a lot of expensive spares. Or stick to very occasional use. Moreover, they tend to clog up rapidly if used with murky water. Not very durable indeed.

The Best Budget Solution
For Odor And Taste

water purification carbon charcoal filtration
Brita carbon filter bottle

Activated charcoal / carbon filter. For all the safe but less palatable tap water in the world. Ideally, the filter can be removed so you only use it when needed. Consider carrying a spare because of the shorter lifespan. We like the convenient Brita water bottle at 250g/8.8oz if you want something that fits in your day pack.  Alternatively, the Platypus Carbon Element plugs into your inline system adding only 30g/1oz. Both will set you back around 20$ and treat around 300 liters of water. 

The key here is to only use it when necessary. Don’t waste your precious filter on water for hot drinks or cooking.

The 3 Best Solutions Lightweight For Safe Drinking Water For Budget Travelers

There is sadly no silver bullet for guaranteeing the microbiological quality of the water. But beyond using local safe water sources, a few items should be in every budget- and environment-conscious traveler’s bag.

water purification chlorine tablets micropure
Micropur chlorine tablets

1. Micropur chlorine dioxide tablets. Although not the cheapest tablets, they are the most effective, especially for murky water. This is the ideal emergency water purification method as it weighs next to nothing. In our opinion every traveler should carry a strip in her/his emergency or first aid kit.

water purification filtration mini sawyer
Sawyer Mini squeeze filter

2. Mini Sawyer filter. It works with a straw or the included squeeze bag. Also it screws onto any standard PET bottle mouth for on-the-go hydration. It has a good flow rate and lasts for an impressive 350000 liters/100000 gallons. Last but not least, it only costs around 20$ and weighs around 60 g / 2 oz. This is a true travel essential. And combined with micropur tablets you can face the occasional suspected viral contamination too. Long-term review here.

3. SteriPEN Ultralight. If you spend more time in developing countries viruses are a regular threat. Despite its shortcomings, you can add a SteriPEN Ultralight at just 80 g / 3 oz. It costs around 70$. Combined with the Mini Sawyer filter it covers a wide range of situations while introducing some welcome redundancy in your system.

The Best All-In-One Long-Term Solution For Budget Travelers

Sawyer Point Zero Two filter. If you plan on regularly treating larger volumes in countries where viruses are an issue, the Point Zero Two replaces the SteriPEN / Mini Sawyer combo.

It has a decent flow rate, at least for an ultrafiltration unit. The filter itself has a (drained) weight of around 185 g / 6.5 oz. Also, it’s fairly big, roughly the size of a small soda can. So it will be a cumbersome addition to your day pack compared to the Sawyer Mini. But it’s simple, and most importantly reliable. And with a lifespan of 1000000 liters / 260000 gallons, it should outlive your travel mojo.

water purification ultrafiltration sawyer zero point two
Sawyer Point Zero Two DIY inline setup with an old MSR bladder

The Point Zero Two was initially designed to be used with a bucket, and comes with relevant accessories. A more practical solution is to use some of the provided tubing to convert it to an inline filtration system with a water bag. Hang up the bag to fill your bottles. Plug a tube with a mouth piece to drink on the go. Add a small inline charcoal filter if poor taste is an issue.

Sawyer sells the kit for around 130$. So it only makes sense if you will be using it for at least a few months. But for little extra money and weight, you end up with a true lifelong solution.