Skip to main content

Discharging grey water or liquid from composting toilets

Discharges of grey water and liquid from composting toilets should be directed to a soakaway. The soakaway should be located at least 50 metres from a water supply and more than 10 metres rom a surface water or permeable drain.

Composting toilets

Composting toilets, or no flush toilets, are sometimes an option for small scale situations in remote areas without access to the public sewer or a water supply.

In the UK, most composting toilets separate out the liquid (urine) and discharge it to a soakaway. This type of toilet is known as a urine-diverting toilet. If you have a urine-diverting toilet you will need a registration to discharge to a soakaway. You can apply for a registration by completing an application form and emailing it to our Registry Team.

Composting toilets with no urine separation can be a problem in our climate as waste doesn't always compost properly. If you have this type of composting toilet there is no discharge. This means you don't need a discharge authorisation.

Properly composted solid waste and the urine from a composting toilet in a private household can be used as fertiliser in line with General Binding Rule 18. Read the Know the Rules Factsheet 8: Organic fertiliser application on the Farming and Water website to find out how to comply with this rule.

Grey water

Grey water is all wastewater except discharges from toilets. This means grey water shouldn't have any faecal waste in it. Sources of grey water includes sinks, baths, showers, and washing machines.

If you are discharging grey water, you will need a registration to discharge to a soakaway. You can apply for a registration by completing an application form and emailing it to our Registry Team.

Related items