Grey Water Treatment

Natural Greywater Treatment


Greywater primary treatment filters


  1. Nature Clear Greywater filter with lid – GWS10

Nature Clear GWS10 is, as of 2011, only approved in Queensland and only as a primary treatment system.

In addition to most Queensland councils, some councils in NSW, NT, and Tasmania have also allowed the installation of Nature Clear.

GWS10 Greywater filter with lid

GWS10 Greywater filter with lid

Nature Clear GWS10 provides a simple and low-cost effective means of treating greywater.   Not only is the equipment low cost, but also, if your site is suitable, the only significant excavation work required to install the system will be the trenching.   The ongoing costs will be similar to those of a standard septic system.

In order for the filtration tank to work most effectively food scraps and grease should be removed from the kitchen wastewater via a grease trap.   A 45-litre and a 150-litre grease trap are available to go with the GWS10.   

Inside GWS10 Greywater filter

Inside GWS10 Greywater filter

The filtration tank, which is about 1 cubic meter in size, consists of a pine bark coarse filter on top of different grades of sand and gravel.  The pine bark traps large particles not caught in the grease trap plus lint from the washing machine. The sand filter catches still finer materials, polishes the water, and reduces the organic content of the water.  The pine bark is separated from the sand by filter cloth.  The filtered material and bark will decompose over time and should be removed every twelve months and replaced with fresh bark, available from your local garden nursery.  If your distribution area is downhill from the filtration tank your engineer should be able to design a distribution system without the use of a pump.  If this is not the case you will also need a pump and pump well.

The treated water must be distributed into trenches as specified by your engineer.  Make sure his calculations of size do not include an allowance for toilet water, which would make them unnecessarily large and expensive.

DIMENSIONS: Length 1020 mm x Width 1020 mm x Height 950 mm

Nature Clear GWS10 has only been approved for use in Australia as a primary treatment system.

In addition to almost all Queensland councils, some councils in NSW, Victoria, and Tasmania have also allowed the installation of Nature Clear.

In other areas, many customers have successfully ‘experimented’ with cleansing their greywater before using it for irrigating the garden.


How it works

Nature clear grey water filter

Nature Clear provides an odour-free method of filtering and cleaning grey water with no moving or electrical parts.  The water from all greywater outlets flows into a polymer tank where it is progressively filtered and biologically cleaned.  From the tank, the treated water flows under gravity into an application area.  The application area materials should be supplied and installed by your plumber.  It may consist of trenches or 150mm subsurface irrigation, depending on local conditions and regulations.

Because the dwell time of the water in the tank is short, there is no time for bacteria to build up, as there is in anaerobic septic tanks.  Consequently, the system should always remain odour-free.

Filtering of the water takes place in several layers of naturally occurring materials separated by progressively finer grades of geofabrics.  A biofilm is established near the centre of the tank where aerobic bacteria clean the water.  The resulting water quality is typically of secondary treatment quality.

There is no disinfection process and consequently most authorities will not allow the water to be disposed of above ground.  Whilst it is unfortunate that the water cannot be disposed of above ground, no chlorination process has been used to disinfect the water.  Please also note that during periods of drought some councils will permit the use of a diverter to allow discharge of the treated water at the surface.

If the application area cannot be fed by gravity, or the local authority insists on a pressurised irrigation system being installed, a pump well and submersible pump will also be required.

The maintenance of the system is very much reduced if a grease trap is installed on the kitchen waste outlet.  Normal maintenance involves replacing the top layer of organic coarse filtration material (pine bark) once or twice a year and annual cleaning of the top two layers of geofabric.  The old materials can be disposed of in your composting toilet or in a suitable area in your garden.  The annual cost is less than $10.

Price: $1750


2. Solazone Tiny house mini Greywater filter

Tiny house greywater primary filter

Tiny house greywater primary sand filter

This is a smaller greywater primary filter tank.

Built to order from our Melbourne and Marcoola warehouses.

Tiny house compact greywater filter

Tiny house compact greywater filter

DIMENSIONS: Length 1020 mm x Width 915 mm x Height 790 mm

Suitable for use of up to 2 people.

Price: $985       


3. Solazone maxi-flow Greywater filter 

With larger pipes for improved filtration.

Solazone Greywater      Solazone Greywater top view

The Solazone maxi-flow greywater primary filter uses bigger pipes to allow for occasional large water flows and reduced resistance to greywater discharge.  It also has a safety overflow hole in the top of the inlet pipe for excessive flows.

Inside of the Solazone maxi-flow greywater filter

Inside the Solazone maxi-flow greywater filter

From our experience of using greywater filters over the years, we recommend leaving the top uncovered so fresh air can dry out the pine bark and stop odours.  In my own case, I have planted pot plants of different grasses in the pine bark to help absorb moisture and attract beneficial insects.  The pot plants are easy to move when you need to replace the pine bark.

DIMENSIONS: Length 1020 mm x Width 1020 mm x Height 950 mm

Price: $1395     


Grease traps


A grease trap is used to remove food scraps and grease from kitchen wastewater before heading to the sand filter.  This will greatly extend the time between cleans of the greywater filter material.

45-litre grease trap

45-litre grease trap

   A 45-litre grease trap is suitable for most households using the greywater sand filter.   This is how it works:

45-litre grease trap - how it works

45-litre grease trap – how it works

Some councils insist on a larger grease trap to extend the life of the trenches.  The 150-litre grease trap only needs cleaning every 1-2 years whereas the 45 L trap needs to be cleaned by emptying the washable filter every 6 weeks or so.


150 litre greasetrap

150 litre greasetrap

150l greasetrap top view


Pump Well


Greywater Pump Well

Everhard’s 250/450 Pump Well has been a robust and effective solution in many domestic and industrial applications for several years. The new spherical design provides the symmetry that customers have been looking for with a deeper invert that provides greater flexibility in a number of usage situations.

Features include:

  • 250 or 450 litre inlet capacity
  • Seamless rotomoulded body
  • Spherical design for increased strength
  • Rubber ring seal fittings provided
  • Lightweight construction
  • Anchorage pockets to resist uplift
  • Risers available
  • Small footprint for economical transportation
  • Tested to ASNZS1546.1


Greyflow drip tube kit

Grey Flow Drip Tube Kit

Kit Includes:

  • 100m x GF Drip Line 9L/Hr @ 0.3m
  • 25 x Straight Take-Off
  • 1 x Budget Punch Tool to suit LDPE Take-Off
  • 2 x 25mm Joiner
  • 13 x 25mm Ratchet Clamp
  • 25m x 25mm Purple LDPE
  • 2 x 25mm Elbow
  • 2 x 25mm Barb Plug
  • 1 x 25mm Tee



Free download:  The Ultimate Guide to Greywater Systems


Greywater system prices Prices April 2024
Greywater tank, complete with lid, fittings & geotech material
Grease trap 45-litre  $300
Grease trap 150-litre  $825
G-Flow Greywater Diverter $1000
250/450L Polymer Pump Well $750
Greywater rotor valve – 6 stations $250
Greyflow drip tube kit $300

Prices are ex-works in Brisbane, Marcoola, or Melbourne, and do not include freight costs or delivery. 

Goods may be picked up at Solazone or can be freighted directly to you.  In either case, a freight charge may apply.


Order now, or ask a question:

Queensland:    (07) 5448 8304      qld @

Victoria:            (03) 9808 7337      vic @

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