FULL OR EMPTY?

Should you travel with water tanks

GUIDE Water Tanks and Travel – Part 1

Out of all the issues that caravanners argue over, the question of full or empty water tanks while travelling is one I’ve never fully understood. As far as I’m concerned, if I needed water at my next camping destination, I’d fill my tanks. Otherwise, I’d travel with them empty. But some people have very strong opinions on both sides of the fence. So, this month, we take an in-depth look at the question and discuss the pro and cons of travelling with your water tanks empty or full.

And why does it matter?

WORDS AND IMAGES MARTY LEDWICH

SINGLE WHEEL CONVERSIONS

PARABOLIC SPRING SUSPENSION UPGRADES

ATB DIFF UPGRADE

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ABOVE It pays to check if water is available at your next destination // BELOW In dry or drought affected areas water is a valuable resource

Stability in windy conditions
Having your water tanks full puts a lot of weight down low in the caravan, lowering the centre of gravity and, supposedly, increasing stability. This is particularly noticeable when driving in windy conditions. Some sections of the Bruce and Pacific highways (in the east) are prone to substantial crosswinds and are notorious for caravan rollovers. Whether or not these are all caused by the wind is debatable however, having additional weigh down low will make the caravan less susceptible to severe crosswinds.

Good quality water supply 
Water quality varies across the country. Some places are blessed with great tasting and clean water straight out of the taps whereas other places aren’t. The reasons for poor quality water are varied but among the usual suspects are a bore water supply, old water pipes or drought conditions. By travelling with your water tanks full, you’ll always have a supply of good drinking water available.

ABOVE We have a separate water tank that is isolated from the other two tanks and is dedicated for drinking water

Keeps your options open 
If you’re the sort of traveller that doesn’t like to plan your trips too much, you may want to give yourself the option of stopping overnight at a free camp rather than keep driving on to the next caravan park. Free camping without water is no fun so having a supply on board at all times means you can pull up for the night anywhere you like and have a shower if you so desire.

REASONS FOR HAVING THE WATER TANKS FULL

“Free camping without water is no fun so having a supply on board means you can pull up for the night anywhere”

As a 4WDing couple, Paul and Donna O’Brien needed peace of mind that they’d get back what they’d invested in their setup if anything went wrong. And they feel more comfortable knowing that they’ve got cover wherever they go, including non-gazetted roads. That’s why they chose to insure with Club 4X4.

Paul O’Brien – Club 4X4 customer

Less wear and tear in the tow vehicle 
The more weight the tow vehicle has to pull, the harder it has to work and that results in greater wear and tear. You may find you will need to do more frequent oil changes when towing especially with the constant need to pull the extra weight of full water tanks. Transmissions also work harder with the additional weight and they may require more frequent servicing as a result.

Less wear and tear on the van’s suspension 
The vast majority of caravans have fairly basic leaf spring suspension. The constant movement in the springs develops friction between the leaves, which causes them to wear out over time. Adding to their workload by keeping your water tanks full means these springs work harder and can wear out much quicker.

TRAVELLING WITH THE WATER TANKS EMPTY

Less cargo capacity for other items
Most tandem-axle caravans will have a cargo capacity of anywhere between 400kg and 600kg. If you have two 90-litre water tanks and you fill them up every time you hit the road, there’s 180kg of cargo gone, and you haven’t stored a single personal item inside the van as yet. The situation could be worse with single-axle caravans.

Instability issues
I often hear caravanners saying that their vans are unstable when the water tanks are empty, therefore they always travel with the water tanks full. They will sometimes get this advice from the caravan manufacturer. A well-designed caravan should be stable regardless of how much water it is carrying.

If you find that your caravan is unstable with empty water tanks, regardless of the prevailing weather conditions, you probably need to look at how other items are stored in it to ensure you haven’t incorrectly distributed the load. Either that or your caravan has a serious design flaw and needs to be checked by a qualified caravan repairer.

Less weight means better fuel economy
There’s no escaping the fact that carrying more water means you're towing a greater weight and, the more weight your tow vehicle has to pull, the more fuel it will use. All tow vehicles are different, but I have noticed our Toyota LandCruiser 200 Series will use an additional one litre of fuel per 100km for every 100 litres of water we have on board. It doesn’t sound like a lot, but over time and distance, with a possible 270 litres of water on board, we certainly notice the difference at the fuel bowser.

BELOW Our caravan has three water tanks that, if all are filled, weigh a total of 270kg

ABOVE It's a good idea to know which filler is connected to which tank

Either full or empty while travelling
It’s possible a lot of people experience instability in their caravans because their water tanks are neither full nor empty. If your tanks are just a third full, the water will move about in the tanks from side to side, shifting the centre of gravity and making the caravan feel unstable. Most caravans will be fitted with quality water tanks that contain baffles that will minimise the effect, although they can’t eliminate it. Where possible, keep your tanks either completely full or empty. If you have to drive with partially full tanks, consider reducing speed to minimise the effect of the water moving in the tanks.

Understand how your tanks work 
It’s important to know how the water pumps draw water from your tanks. Some caravans have the individual tanks interconnected so water is drawn from each tank equally, some can isolate individual tanks, some vans have separate tanks for drinking water. Understanding how all this works means you can track and control how much water is being drawn from each water tank and how the weight distribution changes as you use water.

ABOVE Knowing how your water tanks operate assists with ensuring correct weight distribution

Keep the weight as close to the axles as possible 
If you don’t need to fill up all your water tanks, its best to fill the tanks that are closest to the caravan’s axles. That way you keep the weight over the load-bearing points on the caravan’s chassis. Avoid filling any water tanks placed at the rear of the van unless it is absolutely necessary and that the weight is counterbalanced with water in tanks situated forward of the axles.

TIPS AND TRICKS 

FINAL WORD 
Ultimately, the decision to travel with full or empty water tanks will depend on your individual requirements for any given circumstance. For me, I cannot see the need to drag all that extra weight if you don’t need to. I mostly travel with empty water tanks unless I know I will need the water for free-camping. That said, I do carry some drinking water that I know is good just in case my next destination has poor quality water or if the region is drought-affected. The towns you visit might not be able to spare a hundred litres or so to every traveller that stops by wanting to fill-up, often to only move on again the next morning. Bear this in mind too.

ABOVE Travelling in remote country like this requires full water tanks // BELOW This sign is a common sight across the remote outback of the country. Don't ignore it

GUIDE Water Tanks and Travel – Part 1

FULL OR EMPTY

Should you travel with water tanks

WORDS AND IMAGES MARTY LEDWICH

And why does it matter?

Out of all the issues that caravanners argue over, the question of full or empty water tanks while travelling is one I’ve never fully understood. As far as I’m concerned, if I needed water at my next camping destination, I’d fill my tanks. Otherwise, I’d travel with them empty. But some people have very strong opinions on both sides of the fence. So, this month, we take an in-depth look at the question and discuss the pro and cons of travelling with your water tanks empty or full.

SINGLE WHEEL CONVERSIONS

PARABOLIC SPRING SUSPENSION UPGRADES

ATB DIFF UPGRADE

ADVERTISEMENT
SCROLL TO CONTINUE
REASONS FOR HAVING THE WATER TANKS FULL

Stability in windy conditions
Having your water tanks full puts a lot of weight down low in the caravan, lowering the centre of gravity and, supposedly, increasing stability. This is particularly noticeable when driving in windy conditions. Some sections of the Bruce and Pacific highways (in the east) are prone to substantial crosswinds and are notorious for caravan rollovers. Whether or not these are all caused by the wind is debatable however, having additional weigh down low will make the caravan less susceptible to severe crosswinds.

ABOVE We have a separate water tank that is isolated from the other two tanks and is dedicated for drinking water

Good quality water supply 
Water quality varies across the country. Some places are blessed with great tasting and clean water straight out of the taps whereas other places aren’t. The reasons for poor quality water are varied but among the usual suspects are a bore water supply, old water pipes or drought conditions. By travelling with your water tanks full, you’ll always have a supply of good drinking water available.

ABOVE It pays to check if water is available at your next destination // BELOW In dry or drought affected areas water is a valuable resource

Keeps your options open 
If you’re the sort of traveller that doesn’t like to plan your trips too much, you may want to give yourself the option of stopping overnight at a free camp rather than keep driving on to the next caravan park. Free camping without water is no fun so having a supply on board at all times means you can pull up for the night anywhere you like and have a shower if you so desire.

“Free camping without water is no fun so having a supply on board means you can pull up for the night anywhere”

Paul O’Brien – Club 4X4 customer

ADVERTISEMENT
SCROLL TO CONTINUE
TRAVELLING WITH THE WATER TANKS EMPTY

Less weight means better fuel economy
There’s no escaping the fact that carrying more water means you're towing a greater weight and, the more weight your tow vehicle has to pull, the more fuel it will use. All tow vehicles are different, but I have noticed our Toyota LandCruiser 200 Series will use an additional one litre of fuel per 100km for every 100 litres of water we have on board. It doesn’t sound like a lot, but over time and distance, with a possible 270 litres of water on board, we certainly notice the difference at the fuel bowser.

Less wear and tear in the tow vehicle 
The more weight the tow vehicle has to pull, the harder it has to work and that results in greater wear and tear. You may find you will need to do more frequent oil changes when towing especially with the constant need to pull the extra weight of full water tanks. Transmissions also work harder with the additional weight and they may require more frequent servicing as a result.

Less wear and tear on the van’s suspension 
The vast majority of caravans have fairly basic leaf spring suspension. The constant movement in the springs develops friction between the leaves, which causes them to wear out over time. Adding to their workload by keeping your water tanks full means these springs work harder and can wear out much quicker.

BELOW Our caravan has three water tanks that, if all are filled, weigh a total of 270kg

Less cargo capacity for other items
Most tandem-axle caravans will have a cargo capacity of anywhere between 400kg and 600kg. If you have two 90-litre water tanks and you fill them up every time you hit the road, there’s 180kg of cargo gone, and you haven’t stored a single personal item inside the van as yet. The situation could be worse with single-axle caravans.

Instability issues
I often hear caravanners saying that their vans are unstable when the water tanks are empty, therefore they always travel with the water tanks full. They will sometimes get this advice from the caravan manufacturer. A well-designed caravan should be stable regardless of how much water it is carrying.

If you find that your caravan is unstable with empty water tanks, regardless of the prevailing weather conditions, you probably need to look at how other items are stored in it to ensure you haven’t incorrectly distributed the load. Either that or your caravan has a serious design flaw and needs to be checked by a qualified caravan repairer.

TIPS AND TRICKS 

Either full or empty while travelling
It’s possible a lot of people experience instability in their caravans because their water tanks are neither full nor empty. If your tanks are just a third full, the water will move about in the tanks from side to side, shifting the centre of gravity and making the caravan feel unstable. Most caravans will be fitted with quality water tanks that contain baffles that will minimise the effect, although they can’t eliminate it. Where possible, keep your tanks either completely full or empty. If you have to drive with partially full tanks, consider reducing speed to minimise the effect of the water moving in the tanks.

ABOVE Knowing how your water tanks operate assists with ensuring correct weight distribution

Understand how your tanks work 
It’s important to know how the water pumps draw water from your tanks. Some caravans have the individual tanks interconnected so water is drawn from each tank equally, some can isolate individual tanks, some vans have separate tanks for drinking water. Understanding how all this works means you can track and control how much water is being drawn from each water tank and how the weight distribution changes as you use water.

ABOVE It's a good idea to know which filler is connected to which tank

Keep the weight as close to the axles as possible 
If you don’t need to fill up all your water tanks, its best to fill the tanks that are closest to the caravan’s axles. That way you keep the weight over the load-bearing points on the caravan’s chassis. Avoid filling any water tanks placed at the rear of the van unless it is absolutely necessary and that the weight is counterbalanced with water in tanks situated forward of the axles.

FINAL WORD 
Ultimately, the decision to travel with full or empty water tanks will depend on your individual requirements for any given circumstance. For me, I cannot see the need to drag all that extra weight if you don’t need to. I mostly travel with empty water tanks unless I know I will need the water for free-camping. That said, I do carry some drinking water that I know is good just in case my next destination has poor quality water or if the region is drought-affected. The towns you visit might not be able to spare a hundred litres or so to every traveller that stops by wanting to fill-up, often to only move on again the next morning. Bear this in mind too.

ABOVE Travelling in remote country like this requires full water tanks // BELOW This sign is a common sight across the remote outback of the country. Don't ignore it

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