Overview of greywater management health considerations

ABSTRACT

Much of the daily-generated wastewater is recognized as greywater which represents about 60% of the total generated wastewater. Greywater can be used for different purposes, such as garden watering, ornamental uses in fountains and waterfalls, landscaping, lawn irrigation, car washing and toilet flushing. Greywater reuse utilizes an on-site resource which would otherwise be wasted. As a result of reuse, 40% of the fresh drinking-water supplies are conserved. Greywater reuse succeeds in saving money spent by water authorities, reduces sewage flows and reduces the public demand on potable water supplies. By reusing greywater, the load on wastewater disposal systems is reduced, and therefore, the life of the wastewater disposal system is prolonged and capital expenditure required for the upgrading and expansion of systems is delayed. As greywater is contaminated with faecal coliforms and some chemical pollutants from bathing and laundry, microbial and chemical contaminated of greywater poses a potential risk to human health, and so it is important to recognize that greywater does have the potential to transmit disease. Accordingly, this guide was prepared to act as a set of guidelines and procedures for the safe reuse of greywater. This guide has been prepared to assist government officers, homeowners, site and soil evaluators, designers, installers and service technicians with regard to the safe reuse of wastewater, and to act as a guide in the process of designing, installing and maintaining greywater systems in a manner which protects human health, plants, soil and the environment