Human waste is 90% water. And in regular toilets, all 90% of that polluted liquid ends up in our groundwater, lakes or rivers. The excessive nutrients and pathogens this wastewater contains lead to a build up of potassium and nitrogen in lakes, both of which foster weed growth and blue-green algae development. Such growth absorbs the dissolved oxygen in the lake and eventually works to kill it. More local councils are refusing to allow the installation of septic systems due to the impact they have on the local environment even up to 50m away. Contaminated oysters are just one example of this effect.
Sun-Mar composting toilet systems evaporate excess liquid (up to eight litres per day) and diffuse it into the atmosphere, meaning no contaminated polluted water is released unnecessarily into our water supplies. Whatever liquid that is not evaporated flows through an outlet drain into a small L 2m x W 0.4m x H 0.4m absorption trench. This may be only 1.5L per person per day compared with a septic system which can allow seepage of up to 125L per person per day (sewerage mixed with all other grey water).