The term 'Grey Water' is used for collected water.

The term 'Green Water' is used for reusable water

A cartoon of a window box with flowers.
A Pciture of the BedZed Project

Green Water

Green Water is a generic description for water that has been treated to a quality suitable for provision as a non-potable supply, usually, but not exclusively in parallel with a potable supply, for industrial, residential or public use (examples might include toilet flushing, horticultural/irrigation purposes, laundries, industrial processes or washing, heating/cooling functions.)

[Green water' is sometimes mistakenly referred to as 'grey' water. This should not be the case - 'grey' water is untreated wastewater from baths, basins and showers. Green water is treated.]

The Green Water "Standard" has the following characteristics:

Potable water is provided for the purpose of drinking and must meet all the Drinking water Quality Regulations. Private supplies of Green water to more that a single household are regulated by Local Authority Environmental Health Departments. They have a requirement to sample the water at a specified frequency.

Non-potable Green Water is not yet regulated in the UK and can be treated (or not) to meet specific end-use. There is a Duty of Care by agreement between the supplier and the provider of a service (e.g. the Local Authority) to ensure that the agreed standard is complied with.

The Green Water is distributed through distinct green pipe work developed by WWUK which cannot be inadvertently connected with the drinking water system.