What is Grey Water?

Grey water is household water that has been used for showers, washing dishes and laundry that can be collected and reused. Toilet water is not considered grey water.  more

Grey water is literally the water that comes out in the wash. Not to be confused with black water, which is wastewater that comes from the toilet and garbage disposal, grey water is the wastewater that comes from the laundry, kitchen, bathroom faucets, baths, and showers. Using grey water recycling and treatment systems is an important component of green building methods and practices. Recycling grey water has become more attractive to owners of commercial and residential buildings for the savings in energy and potential environmental benefits. Recycling grey water reduces the demand on sewage treatment plants as well as water treatment plants. An estimated 50 to 80% of all wastewater a residence generates is grey water, which can be put to use in irrigation of the landscaping. Grey water is preferred for this type of recycling, as black water requires much more advanced treatment procedures. Ninety percent of nitrogen in wastewater comes from black water, and nitrogen is one of the ...  more

Grey water is the name given to waste water produced by households - from showers, baths, spas, handbasins, washing machines, laundry troughs, dishwashers and kitchen sinks. Black water is the name given to waste water from the toilet. Typically, each person in a house provided with piped water generates 150 to 200 litres of waste water per day. HOW DO I USE GREY WATER? • A system that diverts untreated grey water for immediate re-use in the garden must be installed by a licensed plumber. Contact relevant water authorities before work begins. • Systems that treat and re-use grey water must be approved by the EPA and the local council must issue a septic tank permit.  more

Grey water is considered all used water that is discharged from a house, excluding black (toilet) water. This includes water from shwers, baths, sinks, dishwashers, laundry tubs, and washing machines. Grey water commonly contains soap, shampoo, toothpaste, food scraps, cooking oils, detergents, and hair.  more