Much of the water we use ends up as waste water. Waste water is produced when we use showers, toilets and machinery in our homes, shops, offices and factories. It is also be produced by polluted storm water from urban and agricultural areas.

However, it is possible to collect and reuse waste water in our homes, offices, factories and farms as it can be treated to the standards required for agriculture, industry and even drinking. Waste water can be redirected prior to treatment, such as when shower water is directly re-used for flushing toilets, or after treatment, such as when treated sewage effluent is used for irrigating golf courses and orchards.