Grey water意思

"Grey water" is a term used to describe used water from domestic activities that has not come into contact with human waste, such as water from showers, baths, sinks, and washing machines. It is called "grey" water to distinguish it from "black water," which is sewage or water that has come into contact with fecal matter.

Grey water is typically treated differently from black water because it is considered to be less contaminated and can be reused for various purposes, such as irrigation, flushing toilets, and even for industrial processes after proper treatment. Recycling grey water can help conserve fresh water resources and reduce the burden on sewage treatment systems.