Short answer: A campervan toilet and water system takes in fresh water from a drinking water tap and produces two kinds of waste: grey water from the sink and shower, and toilet waste. Empty cassette toilets only at a chemical disposal point (also called a CDP or Elsan point) on a campsite or approved facility, never in a drain, river or bush. Grey water goes in a site's grey water drain. Composting toilets separate liquids and solids, which changes how you empty them.
Fresh water
Every van needs a way to carry clean water. That might be a fixed tank with a pump, or a couple of water carriers under the sink. Either way, a few habits keep it clean and safe.
- Fill from a drinking water tap. Campsite taps marked as drinking water are the usual source. Do not fill from taps marked for washing, or from the tap at the chemical disposal point, which is often there for rinsing toilets.
- Use a food grade hose and keep it separate from anything used for waste. A different colour helps.
- Do not keep water sitting for weeks. Empty and refill rather than topping up old water.
- Clean the tank and pipes now and then with a product made for drinking water systems, following its instructions.
- Carry a separate drinking water bottle if you are unsure about your tank. Many people only use tank water for washing and boil it for anything else.
As a rule of thumb, two people being careful with water can make a typical van tank last a couple of days. Showering on board uses far more.
Grey water
Grey water is what goes down your sink and shower: washing up water, toothpaste, soap. It is not toilet waste, but it is still waste, with food scraps, grease and detergent in it, and it smells quickly in a warm tank.
- Empty it at a grey water drain. Campsites and many motorhome service points have one, often a grate in the ground you can drive over.
- Do not empty grey water on the ground at a car park, lay-by or beauty spot. It is one of the main complaints about vans from local people, and it can damage the places we all want to keep visiting.
- Use a sink strainer so food does not get into the tank.
- Choose gentle washing up liquid and soap, and wipe pans with kitchen roll before washing them.
- Rinse the tank with clean water when you empty it to keep the smell down.
Campervan toilet types: cassette and portable
Most motorhomes have a cassette toilet: a fixed bowl with a removable tank that slides out through a hatch on the side of the van. Portable toilets are the standalone version, common in small campervans. They work in the same way.
A chemical or biological additive goes into the tank to break down waste and control smell. A separate rinse additive often goes into the flush water. Follow the dose on the bottle, and look for products described as suitable for septic tanks if you want more places to empty.
To empty a cassette:
- Find the chemical disposal point on site.
- Put on disposable gloves.
- Take the cassette out, carry it upright, and open the emptying spout over the disposal point.
- Press the air release button as you pour, so it empties smoothly without splashing.
- Rinse the cassette with the tap provided, empty again, then add fresh additive and a little water.
- Rinse the area for the next person.
Cassettes are heavy when full. Empty them before they get there, especially if you have a walk to the disposal point.
Composting toilets
Composting toilets, more accurately separating toilets, keep liquids and solids apart. Liquids go into a bottle. Solids go into a chamber with a dry material such as coir or sawdust, which reduces smell. Many self builders fit them because they do not need chemicals and need emptying less often.
- The liquids bottle needs emptying often, typically every day or two depending on use. Empty it into a toilet or a chemical disposal point.
- The solids are not compost straight away. Most people bag them and put them in general waste where that is allowed, or compost them properly at home over a long period. Check the toilet maker's instructions and your local council's rules, and never bury them or leave bags in bins not meant for them.
- Keep it dry. Most smell problems come from liquid getting into the solids side.
Some campsites are not set up for composting toilet users, so ask when you book.
Where to empty legally
The legal and decent answer is the same: only empty toilet waste at a facility designed for it.
- Chemical disposal points (CDPs). On UK campsites the emptying point is usually called a chemical disposal point or CDP. Some sites call it an Elsan point, after a well known toilet brand. Southend-on-Sea City Council's waste guidance uses both names. These are where cassette and portable toilets should go.
- Motorhome service points. Some aires, motorhome stopovers and service stations have a combined service point with fresh water, grey water and a CDP. Our guide to motorhome aires in the UK covers where these are more common.
- At home. Southend council's guidance says that if no proper facility is available you could flush the contents down a normal toilet, which may mean taking it home, or use a specialist waste company. Not all toilet chemicals are suitable for the sewer or for septic tanks. Pitchup warns that the chemicals in many onboard toilets are not safe for the sewer system. Read the label, use a product that says it is suitable, and check with your water company or council if in doubt.
Never empty a toilet into a surface water drain, a river, the sea, a public bin or the ground. Rules and penalties vary by council, so check before you go. If you cannot find a disposal point, the answer is to plan your route around one, not to improvise.
If you are wild camping or using overnight parking, this matters even more. Plan the nights between disposal points, and stay at a campsite every few days to empty and refill. Roam's places to stay map is coming, and service points are part of what it is built to show.
A simple routine
- Every morning: check the fresh water level and the toilet level.
- Every campsite stop: empty the toilet and grey water, rinse both, refill fresh water.
- Every couple of weeks: deep clean the toilet seals and check the cassette for leaks.
- Every season: sanitise the fresh water system.
If you are building a van, now is the time to decide where tanks go and how you will reach them. Our van conversion steps guide covers the order to do it in.
Questions
Where can I empty my campervan toilet in the UK?
At a chemical disposal point (CDP or Elsan point) on a campsite or approved service point. Some councils say a domestic toilet is acceptable if your chemical is suitable for the sewer, so check the label and your local guidance.
Can I empty grey water on the ground?
Do not. Use a grey water drain at a campsite or service point. Emptying on the ground at car parks and beauty spots causes real problems and gives vans a bad name.
Is an Elsan point the same as a chemical disposal point?
Yes. Elsan is a toilet brand, and the name is often used for a CDP on UK sites.
How often do you empty a cassette toilet?
It depends on tank size and how many of you use it. As a rule of thumb, a couple using it fully will empty every two or three days.