Composting Toilets

Why have a Composting Toilet?


Conventional toilets require approximately 45,000 litres per person per year. The conventional septic tank systems may create a whole range of problems.

Many areas are unsuitable for septic systems. These include clay, marshy, rocky, and very steep locations where little absorption can occur in the soil.

Environment and Resource Considerations

Between 30% and 50% of domestic water usage gets flushed down the toilet. Often this most valuable resource ends up polluting waterways, underground water supplies or gets pumped out to sea. It can pollute large areas by soiling beaches, disrupting plant and animal life in streams, and finding its way into underground water supplies.

There are other losses in these types of sewage systems including organic material and major plant nutrients because quite large amounts of nitrogen, phosphorus and potassium are flushed away every day.

Turn a disposal problem into a valuable resource

The Nature Loo not only saves water and avoids disposal problems, but it actually turns a waste product into a valuable resource. The waste product is turned into a rich organic humus that can be used to restore or improve the fertility of the soil without any harmful side-effects.

Compared to aerobic sewerage treatment it also saves you on power requirements as no sludge pumps or stirring mechanisms are required. Generally all that is required to be powered is a very small and energy efficient air circulating fan.

How a Composting Toilet Works

The principle of operation of the composting toilet is very simple. Human excreta is deposited from the pedestal into a container which is kept warm to promote the growth of bacteria. The bacteria digest the human excreta and renders it into harmless compost, while a small fan extracts odours from the remaining wastes and expels them through a vent.

As long as the excreta is stored for long enough at a sufficiently high temperature, the pathogens in the human waste are eliminated.

The Nature Loo works on the aerobic fermentation principle (in the presence of air) which is a much less messy and smelly than anaerobic fermentation (without air).

Aerobic Fermentation requires a smaller and simpler installation but still requires a certain degree of maintenance to keep it operating at maximum efficiency.

It provides a good compost, it is cheaper to install than a digester and is simple to operate. Unlike anaerobic fermentation it has no other by-products.

Installation of a Nature Loo toilet

You will need:

  • 2 meter of 100mm slotted plastic agricultural pipe
  • 1.75 meter of Geotextile mat or hessian
  • 0.3 m³ aggregate (gravel)
  • 50mm PVC pipe to connect the flexible hose to the trench (not required for compact model)

Fluid absorption trench:

  • Overall dimensions: 2m x 400mm x 400mm
  • Top: 100mm top-soil
  • Bottom: 300mm aggregate (gravel)

Emptying your composting toilet - Easy & Safe

Emptying of the Nature Loo compost bins is quite safe to do if the compost has been stored for more than nine months. The chances of a pathogen still being alive by then is very low; the risk is about the same as handling soil from the garden. The compost is then buried in a shallow trench for another six months, and by then no pathogens should still be alive. By this stage, even the Ascaris ova (roundworm eggs), which may have survived until now, are destroyed. The compost which is removed from such a composting toilet does not smell, and has the texture of leaf mould.

Note: Faeces must be decomposed before being applied to orchards. The chamber must be allowed to sit for more than nine months to allow for complete decomposition to occur.

Do not use this waste product in your veggie garden as human faeces may contain human pathogens (disease causing organisms) some of which may remain active for many years. In a composting bed mixed with vegetable scraps and grass clippings the temperature may be raised to over 55°C which is sufficient to kill pathogens.