Innovations: Dual flush toilet

Australia is the driest inhabited continent in the world and water-saving, particularly in times of drought, is paramount. The South Australian bathroom accessories company Caroma was known for being an innovative company - its founder, Charles Rothauser, developed the first one-piece plastic toilet cistern (the water tank above the toilet bowl) in the late 1950s.

In the late 1970s Caroma was awarded a Commonwealth Government industry grant to develop an effective dual flush toilet. In 1981 Caroma launched the first effective dual flush toilet. Two flush buttons operated the Caroma model - one for a full flush (11 litres) to remove faeces and the other for a reduced flush (5.5 litres) for urine. Others had previously developed a dual flush mechanism, but it was operated by only one flush button; pressed quickly for a reduced flush or held down for the full flush cycle. If the button was not depressed for long enough, the flush was not effective. Caroma also redesigned toilet bowl so that less water was required to effectively remove the waste.

The Caroma dual flush toilet was such an efficient water-saving device that all Australian states, other than New South Wales, soon introduced legislation to make the installation of dual flush toilets compulsory in all new buildings. In 1993 Caroma launched a new dual flush toilet which used only six litres of water for a full flush and three litres for a reduced flush (known as the 6/3 litre two button dual flush system).