Water is a valuable commodity and will be increasingly so in years to come. So it may seem odd that we flush our toilets with water that is entirely drinkable, but it’s generally been easier to manage systems dealing with water in this way. After using this fresh potable (safe and drinkable) water, we create wastewater having used tap water to shower with, flush the toilet, or wash our food with.
Wastewater is reusable but must be treated in different ways depending on its classification to make potable again. It is classified as either grey or black water, depending on the type of contamination. ‘greywater’ comes from non-toilet fittings such as the shower or bathroom sink, and ‘blackwater’ comes from toilet-plumbed features, kitchen sinks, and dishwashers. Councils and governmental health boards standards vary but generally wastewater can be reused as follows:
Wastewater processing will normally occur centrally, though this does depend on geography. Greywater can be directly utilised in either the garden (with some caution towards mineral content, like excess sodium) or feeding some blackwater-producing systems such as the toilet.
The main benefit of reutilising water is efficiency, which may be of particular concern depending on local resources and climate. The obvious downside is the capital outlay required for the system(s) needed. Rural areas typically have more use for home-based systems, with limited access to centralised treatment, likely more restrictive water supply, and larger land blocks allowing easier on-site disposal and potential for utilisation. For urban dwellings with centralised processing facilities and not regularly experiencing water shortages, the likely best action is to be conservative with water usage and consider greywater recycling.
Treatment Processes and Systems
Treatment is a multistep process dependent on the grade of wastewater used and resulting grade desired.
You should only consider a council or state accredited system when purchasing a water treatment system.