Off-Grid Water System Solution

What is the off-grid water system solution for The ImPossible House?

I want the ImPossible House to be completely disconnected from the water supply. I want to show that it can be done in a developed, established area, on a small block. Is this a dream? I don’t think so. That is the essence of the ImPossible House – to figure out how to accomplish the impossible.

My requirements are:

Objectives for the off-grid water recycling system:

Here are the water system requirements I need from an off-grid water-based solution:

  1. Recycle all water so that it may be reused for drinking, the garden or the washing machine.
  2. Support a 3-person household.
  3. No water to leave the property (i.e. disconnected from the mains and stormwater).
  4. The cost of the solution is to be less than $30,000 (excluding the engineer fee).
  5. The system must satisfy NSW health regulations.

My Water Treatment System

House Water Filtration System

I want the house to be entirely self-sufficient for water. This means I won’t be connected to the mains in the future. I am frequently asked about my water system and how I will ensure the water is clean and free of bacteria and cryptosporidiosis. John Caley from www.ecologicaldesign.com.au has worked out a system for me that ensures that I won’t end up with any nasty parasites – this is important because my incinerating toilet uses a lot of electricity. So, the less I use it, the better! IF YOU KNOW WHAT I MEAN! My water will undergo a rigorous screening and filtration system that I’ve outlined below (as shown in the infograph). 

The Water Filtration System Process

  1. 1mm fine gutter screening mesh sits in the gutter to catch all leaves and debris before the water flows down the downpipe
  2. Attached to the downpipe is a leaf-shedding rain-head which interrupts the water flowing through the downpipe and catches any debris not caught by the gutter screening mesh
  3. As the water hits tank 1, it goes through the first flush diverter.
  4. The water is then pumped into tanks 2-4, where it waits to be used.
  5. Garden water comes straight out of tanks 2-4 and doesn’t need more filtration.
  6. The house water is drawn from the top of tanks 2-4, which is cleaner as any sediment left has fallen to the bottom of the tanks. House water then gets pumped through two sediment filters (a 20-micron and a 5-micron filter) before entering the house and is used for showering, dish and clothes washing, etc.
  7. Drinking water goes through one more 1-micron filter before being funnelled into the kitchen and bathroom taps.

Below is a video of John walking me through the system once it’s been gone in. 

My Grey Water System

Summary of the ACQUA Clarus System (M800sx Greywater Treatment System)

Purpose: The M800sx is an advanced greywater treatment system designed for homes with up to 4 bedrooms (8 occupants). It treats up to 720 litres per day and can handle peak loads of 1000 litres per day.

Key Components:

There is a below-ground Grey Water Collection Tank. This collects and strains:

  • greywater, removing debris like hair and lint

Then there is an above-Ground Treatment Unit. Which includes:

  • Bioreactor: Breaks down organic matter.
  • Membrane Filter: Further filters water.
  • UV Disinfection Unit: Sterilises water for reuse.
  • Treated Water Storage Tank: Stores treated water for household reuse or discharge.
  • Pumps and Alarms: Ensures system operation and alerts users to issues.

The flow process is:

  • Greywater is collected in the below-ground tank, strained, and pumped to the above-ground treatment unit.
  • The water is treated through bioreaction, filtration, and UV sterilisation.
  • Then treated water is stored or used for household purposes. Backflushing ensures membrane cleanliness.
  • Solids are discharged into an adsorption trench.

Additional Information

For those looking at systems like this. Here is some additional information: The M800sx system is environmentally friendly and highly efficient, using only as much power as a 60W light bulb operating continuously. It avoids harmful chemicals like chlorine, relying instead on cutting-edge membrane and UV filtration technologies. The system is approved for use in NSW and adheres to strict standards for water quality, achieving results such as BOD5 less than 10 mg/L and faecal coliforms below 5 mg/L. Remote monitoring ensures potential issues are detected early, providing peace of mind. Its compact design allows it to fit against a house, making it ideal for domestic installations.

Check out my water blog as I explored the viability of my off-grid water system objectives with my team.

Follow my journey here