Estimate real daily use
Drinking, cooking, washing and cleaning all draw from the same supply. A remote route usually needs more reserve than a trip moving between serviced campsites.
Campers & Touring · Water answer
How Much Water Should an Overland Vehicle Carry?
There is no single correct water-tank size for touring. Capacity should follow the people, route and refill opportunities while staying inside the vehicle's realistic payload.
Planning guidance — final supplied configuration remains project-specific.
Treat every litre as payload
A litre of water contributes roughly a kilogram before the tank, pump, hose and fittings are counted. Capacity is therefore a vehicle-load decision as well as a convenience decision.
Keep the system clean and accessible
Filling, draining, cleaning, pump access and leak inspection should remain practical once storage is loaded around the tank.
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