How it’s calculated
Fresh water days = fresh tank (L) ÷ (people × 11 L)Grey water days = grey tank (L) ÷ (people × 9 L)Days off grid = whichever of the two is lower
11 litres of fresh water and 9 litres of grey water per person per day cover drinking, cooking and washing up with careful use. Showers on board use far more.
Worked example
A campervan with a 100 L fresh tank and a 90 L grey tank, travelling with two people.
Fresh: 100 ÷ (2 × 11) = 4.5 days. Grey: 90 ÷ (2 × 9) = 5.0 days.
The fresh tank runs out first, after about four and a half days, so plan a refill before day five.
Assumptions
- The per-person figures are averages. Hot weather, cooking with water and showers raise them.
- Toilet cassettes are a separate tank and are not included.
- Empty grey water only where it is allowed, such as a dump point or an approved site.
Cost and planning guides
Common questions
How much water does one person use per day in a campervan?+
This calculator assumes about 11 litres of fresh water per person per day for drinking, cooking and washing up, and about 9 litres of grey water. A daily shower on board uses far more, so plan for it separately.
Which runs out first, fresh or grey water?+
Whichever tank gives the lower number of days. With the same tank sizes, more people or more washing shortens both; the calculator shows the two side by side so you know which one sets the limit.
In the app
Find the next refill and dump point.
AussieCamps maps 3,004 water filling points and 1,393 dump points across Australia, with the facilities each one lists.
AussieCamps is free to download. Bookable stays and tours are free to browse; campgrounds, rest areas, dump points, water, toilets and the trip planner need the Pass. AussieCamps is an iPhone app.
