Motorhome water and waste management is the least exciting part of living on the road, and also the part that causes the most arguments. Nobody posts photos of their grey water tank, but get it wrong and you will know about it very quickly. After years of touring, first in our Elddis Autoquest and now in the Swift KonTiki, I have settled on a simple routine that keeps things boring, which is exactly what you want.
This is the practical version. No jargon, just what to do and when.
Understanding your motorhome fresh water system
Your fresh water tank feeds the taps, the shower and usually the toilet flush. It sits either under the floor or inside a locker, and most come with a drain valve and a filler point on the outside of the van.
Two things matter more than anything else here. Water that sits still goes off, and plastic tanks grow biofilm if you let them. So the aim is to keep water moving and to sanitise the system on a regular schedule.
How much fresh water should you carry?
Water is heavy, and a full tank eats into your payload. I wrote about that in my guide to motorhome payload and weight limits, and it is worth reading if you tend to overpack.
My rule is simple. I travel with a quarter to a half tank, and fill up when we arrive at a site. If we are heading somewhere with no hook up, I fill fully on the day and accept the extra weight for a short drive.
Sanitising your motorhome water tank
Do this at the start of every season and after any long layup. Use a proper tank sanitiser, such as a Milton style tablet or a dedicated motorhome product, and follow the instructions on the packet rather than guessing the dose.
Fill the tank, add the sanitiser, run every tap until you smell it, then leave it for the time stated. Drain, flush through with fresh water two or three times, and you are done. It takes an afternoon and it is worth every minute.
Use a filter at the filler point
I fit an inline filter on the hose I use to fill up. It costs very little and catches the worst of what comes out of a site tap. I also never use a hose that has been left lying in the sun, because warm stagnant water in a hose is exactly what you are trying to avoid.
Managing grey water without upsetting anyone
Grey water is what goes down the sink and shower. Most vans hold somewhere between 40 and 100 litres, and a family shower routine will fill it faster than you expect.
Where you can, use the site waste point or a drive over drain. On a hook up pitch with a designated grey water drain, be tidy and use a hose with a proper fitting. Dumping grey water on grass or into a surface drain is poor form and gets places banned, so please do not.
Cut down grey water use
Short showers help, as does washing up in a bowl and tipping that into the drain at the service point. A shower head with a flow restrictor makes a real difference on an off grid stay. We get three or four days between empties with a little discipline.
Toilet cassette tips that actually work
The cassette toilet gets a bad reputation that it mostly does not deserve. Used properly, it is clean, simple and nowhere near as grim as people expect.
Use a decent toilet fluid in the cassette and a small amount of fresh water in the flush tank. Empty it before it is completely full, because a heavy cassette is awkward to carry and more likely to slosh. Tip it at an Elsan point, rinse it, and top it up with fluid and a splash of water.
Use proper motorhome toilet paper, or at least a quick dissolving brand. Normal thick paper clogs the blade and can turn a ten minute job into a very bad afternoon.
What about the smell?
If your van smells, it is nearly always one of three things. The cassette needs emptying, the slide valve is not closing properly, or the vent is blocked. Check the seal, keep it lubricated with a little silicone grease, and the problem usually disappears.
Motorhome water and waste in winter
Frost is the real enemy. A frozen water pump or a cracked pipe will end a trip and cost real money. If you tour in the colder months, I covered heating in my motorhome gas and heating guide for autumn and winter, and the two topics go hand in hand.
If the van is going into storage, drain everything completely, open all the taps, and leave the drain valves open. Our storage routine is in my winter storage guide. Never rely on the heating to protect a half drained system.
A simple routine you can copy
Here is the whole thing in one go. Arrive, fill fresh water through a filter, and check the grey tank level. Use the Elsan and waste point on the way out, and rinse the cassette every time.
At the start of the season, sanitise the tank and flush it through. Before winter, drain the lot. Keep spare toilet fluid and a hose with the right fittings in a dedicated locker so you are never caught short.
This is the sort of boring system thinking I apply to everything, including my day job. If you are curious how I work and travel at the same time, have a look at how I work remotely from a motorhome, or see what I do on the services page.
Get the water and waste routine right and you stop thinking about it entirely. That is the goal. The best motorhome plumbing is the kind you forget exists.
