The simplest of all overland vehicle water systems is the humble jerry can. It’s a proven, trust worthy solution to hold 20 litres of water in a robust container. Throw it in the back of your vehicle, strap it down and you’re good to go.  Add a 10 litre solar shower pack secured to the roof rack or bonnet (hood) and you now have a simple method for heating a little water too. Assuming of course the sun is shining. It wasn’t so long ago that this was as good as you could get and for many, this is still the most appropriate set up.

Overland Vehicle Water Systems

Fixed Water Tanks

With only 30 litres of water, you’re sure to need to maintain a regular and clean water source. Of course, you can reduce the frequency by adding more jerry cans. Or you could go down the fixed water tank route. Fitted tanks refine your load and space usage. In our 4x4s, we used a 60 litre fixed slim line tank, fitted between the wheel arches and secured behind the rear seat.  It didn’t take up much load space, nestled low down between the axles and aligned across the centre line of the vehicle. It worked really well for us. Fitted with a 2m hose and nozzle that ran out of the back door, we coped with this flexible set up for over a decade.

Both of the above solutions are limited with the amount of water you can carry and in fairness, the solar shower provides little more than a ‘cats lick’. That said they are simple and robust and so long as you manage your water usage carefully, they are perfectly acceptable.

Overland vehicle water systems have become more eloquent. Larger vehicles can cope with carrying larger loads and, after fuel, water becomes the next big ticket load item. Larger overland campers and trucks are often used effectively as motorhomes for medium to long term expeditions. Fitted water systems and showers have become common. Even including a washing machine or ice maker are on an upward trend. The list of water using luxuries is on the increase!

What Size Water System?

I have seen trucks fitted with 1000+ litre water tanks, which is fine until you need to fill up in more remote regions. Finding this amount of water can be a challenge; there are not many garden taps once out of Europe. Even if you find a hand pumped well in a remote African village, you ought to consider the local residents and not take too much of their supply; it’s probably limited. In addition, 1000 litres of water weighs 1 tonne and uses a cubic metre of load space. These implications probably outweigh any benefit.

How to calculate your needs?

We each need to drink a minimum of 2 litres a day in temperate climates. In hot climates, particularly where humidity is high and you may be working hard, that intake could increase to a massive 19 litres. Just for drinking. You might like to have the occasional shower. An average shower uses 35 litres of water and even if you adopt the military approach (tap on, get wet, tap off, soap sud up, tap on, quick rinse off) you will still use around 12 litres. You could always share the shower with your travelling companions to save a little.

Include water for cooking, cleaning house and washing clothes, then you could easily consume 50 litres a day.  There are plenty of creative ways of conserving water and limiting your usage but in discussion with other long term overlanders, we reckon frugal users will average 25 litres per day, per couple.

Top Tip: plan for a simple system with sensible volumes of water. Depending on the number of passengers, where you’re planning on travelling to and expected availability of potable water, your assessment will differ. Just remember the weight and space implications. There’s no need to use a sledgehammer to crack a nut.


Check out: The best advice for modifying your overland vehicle

Simple Hot and Cold Water System Layout

Regardless of size of your vehicle, having hot water on tap is definitely a nice to have, even more so for long term travel. It makes personal hygiene, washing up and cleaning a lot easier. Aside from using a solar shower pack on your roof, there are a few ways to heat your water. We have a highly efficient water system onboard the Unimog. It gives the 2 of us enough water to comfortably go 5 days without a refill. 10 days if we’re ultra efficient.

Our system is explained simply here:

We use a calorifer to heat our water. This acts as a heat exchanger and uses the engine cooling system pumping round a coil in a separate water tank to heat the domestic water. Some models even allow for an immersion heater to be fitted, useful when you are hooked up to AC power.

The system is a closed loop system i.e it is a pressured system that allows the cold water tank to decant into the calorifer when hot water is used. This reduces how long the water will remain hot, but it simplifies the entire system to be able to run on one water pump.  By attaching a micron filter into the system, you have clean water on tap – excuse the pun! Particularly useful if you’re not certain of the cleanliness of the water source. The electrical pump used on our water system is a 12v dc shoreline marine fresh water pump. Despite it’s reliability I still carry 2 x 20 litre jerry cans filled with water, just in case.

Hopefully the slide deck is self explanatory, but if you want more details or information on water systems, drop us a line using the comments below and we will answer any questions you have.

Fun Survival Tip: if you’re sticking with the jerry cans, then here is a really neat trick on how to boil water without a metal pan. Light a fire, place a rock in the middle it for an hour or so, pick up the a rock and place in the bowl or rock pool, assuming that you don’t try and boil an ocean, then you will heat up a small amount of water to boiling point. Hot clean water, bloody brilliant survival tip! Move over Bear Grylls!


Check out: A Simple Guide for Overland Vehicle Electrics

Are you considering modifying your vehicle? You may find some of these posts useful!