Greywater Treatment: F.A.Q.
My Nature Loo composting toilet will keep me from polluting and wasting precious water by not flushing it away. But what about the rest of the water I use?
Councils are increasingly reticent to allow new homeowners to dispose of Greywater without treatment. The days of being allowed to spray wastewater untreated onto the garden have come to an end.
What options do I have for treating Greywater?
Each state and council have their own regulations and you will need to speak to your local council to establish what they will permit alongside a waterless toilet. By way of example the following explains our understanding of the situation in Queensland.
Primary treated wastewater must be disposed of in subsurface trenches. Septic tanks are the main example of systems that treat only to the primary level. Secondary treated water can be disposed of at ground level either via mulch beds or drip irrigation. Aerated water treatment systems (AWTS) treat to secondary level. Such systems include a disinfection unit, most commonly using chlorine. These systems typically cost around $5,000 plus a similar amount for in ground installation. There are then annual inspection and maintenance fees plus wear and tear on the pumps and aerators and electricity costs totaling some AUD $500 per year.
What solution does Nature Loo offer?
In order to satisfy the new state requirements Nature Loo has developed a Greywater system which cleans waste water via natural aeration and gravity fed sand filtration. We are in the process of applying for secondary treatment approval. In the interim the system is approved for primary treatment. Please propose the system to your geotech and/or council.
What do I need to do to get a Nature Clear System approved?
Your council will probably ask you for a site plan. You will need to engage a geotechnical consultant or engineer to test your soil and produce a plan for distribution of the treated water. Make sure your engineer allows for the lower volume of water associated with a waterless toilet. This should result in trenches only 65% of the length of trenches for septic systems handling both black (toilet) and Greywater. You should check before engaging the engineer that they are happy to work with you in designing a system which is based on waterless toilets. We sometimes can help with finding what we consider to be unbiased engineers.
If your council or geotechnician will not allow the installation of Nature Clear then you can still propose a waterless toilet with treatment of Greywater via a conventional holding or septic tank. We would also appreciate the opportunity to speak to your council and provide the latest test results on Nature Clear.