The Complete Caravanners’ Guide To Carrying Water

Water is your lifeline on the road. Get it wrong, and you’ll be cutting your trip short or rationing showers at the worst possible moments. The good news? Once you understand the options, setting up a reliable water system becomes straightforward.

This guide breaks down everything you need to know about carrying water in your caravan: tank sizes, materials, pumps, filtration, and monitoring systems. By the end, you’ll know exactly what setup matches your travel style and budget.

How Much Water Capacity Do You Actually Need?

Water capacity planning starts with understanding your consumption patterns. A family of four typically uses 120-150 litres per day when living normally (showers, cooking, cleaning, drinking). Solo travellers or couples can get by on 60-80 litres daily.

But here’s the critical factor: how long between reliable water sources? If you’re sticking to caravan parks and towns, a 100-120 litre tank gives you 2-3 days buffer. For serious remote travel, you’ll want 200+ litres minimum, potentially split across multiple tanks.

Weight becomes the limiting factor with larger tanks. Water weighs 1kg per litre, so a 200-litre system adds 200kg to your rig when full. Check your caravan’s payload capacity before committing to massive tanks.

Standard caravan tank sizes range from 80 litres (weekend tourers) to 160 litres (family vans) to 240+ litres (off-grid rigs). Most manufacturers offer multiple tank configurations, so you’re not locked into their base capacity.

Fresh Water Tank Materials: Poly vs Steel vs Fibreglass

Your tank material affects taste, durability, weight, and cost. Here’s what each option delivers:

Polyethylene (Poly) Tanks

Poly dominates the caravan market for good reasons. Food-grade polyethylene doesn’t affect water taste, resists UV damage, and handles temperature changes without cracking. Quality poly tanks last 15+ years with minimal maintenance.

The Camec Slimline Water Tank ~$280-450 represents the standard here. These tanks mould to fit underslung spaces efficiently and include proper baffles to prevent water surge.

Poly’s main weakness is impact resistance. A solid rock kick can puncture thinner tanks, though quality units use 10-15mm wall thickness to minimize this risk.

Stainless Steel Tanks

Steel tanks offer maximum durability and don’t expand/contract like poly. They’re practically puncture-proof and maintain water temperature better. The trade-off is weight (30-40% heavier than poly) and cost (2-3x more expensive).

Steel makes sense for serious off-road tourers who prioritise durability over weight savings. The Australian RV Stainless Tank ~$750-1200 sets the benchmark for quality here.

Fibreglass Tanks

Fibreglass splits the difference between poly and steel. It’s stronger than poly, lighter than steel, and can be moulded into complex shapes. However, fibreglass requires more careful handling during installation and costs significantly more than poly.

Most caravanners stick with poly unless they have specific durability concerns or unusual space constraints requiring custom shapes.

Tank Mounting Options: Underslung vs Internal

Tank mounting affects your van’s centre of gravity, storage space, and accessibility for maintenance.

Underslung Mounting

Underslung tanks mount beneath the caravan chassis, keeping weight low and preserving internal storage. This is the most common setup and generally the best choice for stability.

The downsides: exposure to road debris, potential freezing in extreme cold, and limited access for cleaning or repairs. Quality underslung installations include stone guards and insulation to address these issues.

Internal Mounting

Internal tanks mount inside storage compartments or dedicated tank bays. They’re protected from weather and debris, easier to maintain, and won’t freeze as readily.

The trade-off is higher centre of gravity (affecting stability) and reduced storage space. Internal mounting works best in larger vans where storage isn’t at a premium.

Combination Systems

Many serious tourers run multiple smaller tanks instead of one large tank. A 100L underslung tank plus a 60L internal tank gives you 160L total capacity with redundancy if one tank fails.

Split systems also let you carry different water types (filtered vs unfiltered) or maintain one clean tank while using another for washing.

Water Pump Systems: 12V Pressure vs Accumulator Tanks

Your pump system determines water pressure, flow rate, and how smoothly your taps and shower operate.

Standard 12V Pressure Pumps

Most caravans use basic 12V diaphragm pumps that start when you open a tap and stop when you close it. These pumps are simple, affordable, and reliable, but they cycle on/off constantly and provide inconsistent pressure.

The Shurflo 4008 Series ~$185 dominates this category. It’s quiet, self-priming, and delivers consistent 45psi pressure at 11 litres per minute.

Accumulator Tank Systems

Accumulator tanks store pressurised water, so your pump runs less frequently and provides steadier pressure. The pump fills the accumulator, which then supplies water until pressure drops and triggers the pump to refill.

Accumulator systems deliver better shower pressure, reduce pump wear, and eliminate the pulsing flow that basic pumps create. The Shurflo 2-Litre Accumulator ~$120 transforms any basic pump system.

Variable Speed Pumps

Premium variable speed pumps automatically adjust flow rate to match demand. They’re quieter than standard pumps, provide consistent pressure, and reduce power consumption.

The Whale Watermaster ~$350 represents the top tier here. It’s whisper-quiet, delivers excellent pressure control, and includes integrated pressure switch.

Water Filtration and Treatment Systems

Australian town water varies dramatically in quality. Some sources taste fine straight from the tap, others are heavily chlorinated or contain sediment that affects taste and clogs appliances.

Basic Inline Filters

Inline carbon filters remove chlorine taste and basic sediment. They install between your tank and pump, filtering all water entering your system. Basic units cost $30-60 and need cartridge replacements every 3-6 months.

The Camec Inline Water Filter ~$45 handles most caravanning needs. It removes chlorine, improves taste, and includes a clear housing so you can see when the cartridge needs changing.

Multi-Stage Systems

Multi-stage systems combine sediment filtration, carbon treatment, and sometimes UV sterilisation. They’re overkill for most town water but essential if you’re filling from questionable sources.

Point-of-Use vs Whole-System Filtration

Point-of-use filters mount under your kitchen sink and only filter drinking/cooking water. They’re cheaper to maintain since you’re not filtering shower and washing water.

Whole-system filters treat all water entering your caravan. They’re more expensive to maintain but protect your entire system from sediment and extend appliance life.

For most caravanners, a basic inline filter provides the best balance of water quality improvement and maintenance cost.

Water Level Monitoring: Gauges, Sensors and Smart Systems

Running out of water ruins trips fast. Reliable monitoring prevents nasty surprises and helps you plan refill stops.

Mechanical Level Gauges

Basic sight gauges show water level through a clear tube connected to your tank. They’re foolproof, require no power, and cost under $20. The downside is you need physical access to read them.

Mechanical gauges work best for internal tanks where you can easily check levels. For underslung tanks, remote monitoring makes more sense.

Electronic Tank Monitors

Electronic monitors use sensors in your tank to display level on an internal panel. Basic systems show empty/quarter/half/three-quarter/full readings, while digital units display percentage levels.

The CBE Tank Level System ~$180 uses capacitive sensors that don’t require tank modifications. It’s accurate, reliable, and displays both fresh and grey water levels.

Smart Monitoring Systems

Smart systems connect to your phone via Bluetooth or WiFi, providing detailed usage tracking and low-level alerts. They’re overkill for weekend trips but valuable for extended touring.

The SeeLevel II ~$320 provides smartphone monitoring with usage history and customizable alerts. It tracks fresh water, grey water, and black tank levels.

Plumbing and Connection Considerations

Your plumbing setup affects system reliability, maintenance access, and winterisation capabilities.

Hose and Fitting Quality

Food-grade hose prevents taste issues and meets health standards. Standard garden hose isn’t suitable for drinking water systems due to plasticisers and potential bacterial growth.

Use reinforced potable water hose rated for caravan use. It costs 2-3x more than garden hose but maintains water quality and handles pressure cycling better.

Pressure Relief and Safety

Install pressure relief valves to protect your system from over-pressure damage. City water connections can exceed 80psi, well above what caravan fittings handle safely.

A quality pressure regulator like the Camco Brass Water Regulator ~$35 protects your entire system from excessive pressure when connected to mains water.

Winterisation Provisions

If you travel in freezing conditions, your system needs proper drainage and bypass capabilities. Frozen pipes burst and ruin your trip plus cause expensive damage.

Install low-point drains at system low points and bypass valves around your hot water service. This lets you completely drain the system or circulate antifreeze for freeze protection.

Our Water System Recommendations

Here’s what we’d install based on different travel styles and budgets:

Budget Setup ($400-600)

For basic touring, a 100L underslung poly tank with Shurflo 4008 pump and basic inline filter covers your needs. Add a mechanical gauge and pressure regulator for mains connections.

Premium Setup ($1200-1800)

Step up to a 160L tank with Shurflo pump plus accumulator tank for better pressure. Include electronic monitoring, multi-stage filtration, and proper isolation valves throughout the system.

Ultimate Setup ($2500+)

Large stainless tanks, variable speed pumps, smart monitoring, and comprehensive filtration. Include multiple tanks for redundancy and separate filtered drinking water systems.