How to purify water in a vehicle?

Purifying water is one of the most important things to think about when considering living in a vehicle. Even if other alternatives exist , being able to purify your own water is an incredible possibility that allows you to escape from civilization for days without having to worry about water. Indeed, being able to purify water means being able to survive days off the beaten track by drinking from natural water points, lakes, rivers, rain and even muddy puddles. 

To go further : WHO determines quality guidelines for drinking water . In this 500-page document, we find the explanations and recommendations of the WHO to avoid water-borne diseases .

In this article, I will detail the different water purification methods that can be installed in a campervan / camper van or converted truck. There is no question of testing various products. It is only a question of informing oneself and understanding how the various existing processes work. From there, you will have all the information to make your choice of system. You will choose according to several criteria: the space available in your vehicle, the quality of the water you plan to use (to be determined according to the countries visited) and the filtration / purification / disinfection precision you want. Once your chosen system, you can go see the comparative products I conducted according to different methods!


First of all: the need for a good cleaning of the system

Before thinking about purifying the water, think about cleaning all the conduits through which the water will flow. Logically, there is no point in storing perfectly healthy water in a contaminated tank! Cleaning, descaling, everything is detailed in a dedicated article.


Natural water purification solutions (or emergency solutions)

Have you already moved into your van and are wondering if it is good to drink the water directly from the motorhome tap? This is what happened to me, and I was buying bottled water for 2 weeks while i was thinking about it. I was not aware of the simple but effective purification processes that I am revealing to you here!

Two natural solutions make it possible to obtain water free of pathogenic germs (or almost): the boiling treatment and the solar treatment. These solutions cannot be used on a daily basis because they take a long time to implement and do not produce results on chemical substances. This is why they are here qualified as an emergency solution.


Boiling treatment

Boiling will kill all pathogens. You have to filter the water using a cotton cloth, then boil the water. From the appearance of large bubbles (strong boiling), count one minute at low heat, against three minutes at high heat.

This solution requires fuel to heat the water (1kg of wood for 1L of water or gas), it gives the water a bland taste, and has a short shelf life. However, it is an excellent way to purify your own water if you are equipped with gas, compared to the plastic bottle solution!


Solar disinfection treatment: the SODIS method

This solution destroys most pathogenic germs (viruses, bacteria and parasites (Giardia and Cryptosporidia). You just have to leave the bottles (plastic or glass) in direct sunlight for 6 hours (if the sun is blazing, it takes longer if the weather is bad). The cost is inexistent, but you should not be thirsty if the sun is not there.

Purification solutions to integrate into the vehicle system

There are many solutions to integrate directly into the vehicle. Neither seen nor known, once installed these little technological jewels take care of purifying your water. The products available on the market are numerous, and their efficiency / price is doubling.

The purification methods have to be integrated into the vehicle dependent on the length of the circuit you wish to purify. Either you choose to purify upon filling, or you purify in the tank, either before or after the tap. This will depend in particular on your installation and the number of taps you have. If you want to use two taps, it may be economically better to choose one tank purification rather than two tap purifiers!


Purification before filling the tank

The first solution is to clean the water as soon as the tank is filled. The water is disinfected / purified even before touching the motorhome / van / fitted vehicle. For this process to be effective, it must be ensured that the water is stored in elements which are not themselves contaminated. This requires regular and thorough manual cleaning of the entire water supply system, from the tank to the tap.

The systems are all or almost identical: they are small filters that clip to the pipe you use to fill your tank. Some are clipped directly onto the filling orifice and therefore do not require any venting of the tank: increased ease of use and reduced risk of contamination.

This system is therefore easy to install and use, and takes up little space. The cost is quite low to purchase for some models. However, this solution is not possible if the filling cannot be carried out with a pipe… which is not always possible.


Purification of the water inside the tank

Another solution is to purify the water directly from the tank. This time, three methods are available on the market: ultraviolet, electrolysis (ozone) and the use of chemical additives (chlorine dioxide, chlorine, bleach, silver ions, colloidal silver) . These solutions are interesting because they allow constant cleaning of the tank itself, and therefore prevents the formation of bacterial biofilm in the tank (viscous wall that is found on all the elements immersed in water for a certain time. without cleaning, a bit like in an aquarium).

Today, UV-C irradiation technology is used in many industries to fight against the proliferation of harmful and / or pathogenic organisms. The medical environment, the aquatic environment and the food industry use it daily to eliminate viruses and bacteria . This solution has therefore been proven for several decades and finds its place alongside chemical processes whose effectiveness is well established. Ozone water purification is a process that has been used by public drinking water disinfection services and has now become accessible to individuals.


Water purification after the water pump / tank

It is also possible to install a water purifier after the water pump. They are most of the time filters, more or less filtering according to their dimensions.

This solution is advantageous if there are several taps inside the vehicle. For example, at home, I have three water points: the kitchen tap, the bathroom tap and an outdoor shower. The fact of purifying after the water pump further reduces the length of the water conveyance circuit, as we know, the longer the circuit after filtration, the greater the risk of contamination.

In the case where the vehicle has only one tap, the water filtration solution at the tap is more than interesting and is even to be preferred in comparison with a filtration after the tank or the water pump. .


Water purification just before or just after the tap

First choice solution for small vans or converted trucks that only have one tap in their vehicle. Can also be a good choice for those who wish to have pure water only on one of the taps of the vehicle! Filters are sold on the market to be positioned just before the tap or at its outlet, as well as reverse osmosis units.


Portable systems requiring no installation

For all those who are afraid of leaking, there is a solution! No need to touch the vehicle’s water circuit if you opt for a portable solution. The flip side is that you won’t have clean water in your taps. The water that comes out cannot be used for your consumption. It is neither drinkable nor suitable for washing your vegetables. And this even if you have filled your tank in a campsite or any other drinking water point! Because I repeat, but the dirt in your tank, your pipes and the heat greatly impact the quality of the water in your tank. Without the possibility of being controlled, it is always safer not to consume it!

There are many portable solutions to purify your water, ranging from straws to gourds to 12 liter gravity filters.



The closer the purification occurs to the moment of consumption, the better. The logic is as follows: all the elements through which the water passes after being decontaminated are liable to re-contaminate it. However, decontaminating upstream of the tank also has its advantages, such as preventing the creation of a biofilm. The best would be to filter your water in all possible ways: before the tank, after the tank and after the tap.