Is it safe to reuse greywater?
Yes, if used in an appropriate way. Greywater can contain disease-causing micro-organisms such as bacteria, protozoa, viruses and parasites. It may also contain fats, oils, detergents, soaps, salt, nutrients, food and hair derived from household and personal cleaning activities. These constituents can pose both health and environmental risks. However, the public health risks associated with onsite reuse of domestic greywater are considered low, as the source of the contamination would be from the immediate family. Other sources of transfer of pathogens around the immediate family would be considered a higher risk, such as direct physical contact or sharing of food and utensils. Similarly the risk of environmental damage from the careful use of greywater is low.
