A dual flush toilet is a better version of regular flush toilets that incorporates the use of handles to flush dissimilar quantities of water depending upon the kind of waste. An Australian sanitary ware company Caroma was the first to manufacture a dual flush toilet in 1980, inspired by the design proposed by industrialist Victor Papanek four years earlier. Initially it was designed with flush volumes of 1 liter and 5.5 liters, which was later upgraded to accommodate 3 to 6-liter capacities. Word spread about this new innovation quickly and within no time it was adopted worldwide including in countries like New Zealand, Israel and Singapore etc.


Dual flush toilets

Dual flush toilets vary in complexity of design and functioning mechanism.  A push button toilet differs from the traditional siphon flush toilet. The conventional push button kind uses buttons to regulate the amount of water being flushed, while the siphon flush one depends on gravity to eliminate the waste from the commode. Push button toilets require less water due to lack of siphoning which is because the water line is considerably lower. The two buttons on the cistern are used to switch between releasing different volumes of water. One that delivers 3 liters of water is used to flush liquid waste. The second 6-liter button is for flushing down solid wastes. Additionally, they use a bigger 10 cm trap way in the bowl permitting water to emerge quicker thereby clearing the bowl more effectively. These toilets are also manufactured with handles instead of buttons. In this case if the flush handle is seized down in its place of being let go soon after flushing, they function as a half flush letting out 3 liters and if the handle is freed immediately then full flush mode liberates 6 liters of water.

Boons and banes

These modern toilets are highly efficient as they save a lot of water. The original 4.5 to 9-liter capacity flushes were improved to 3 to 6 liters and constant trials are being conducted to reduce the numbers even further. However, most times people aren’t aware of the working of the two buttons and follow only one pattern of flushing all the time, which doesn’t fulfil the purpose of design.

The only real disadvantage about double flush toilets is that they are not as cost effective or budget friendly compared to the single flush or the standard American style variety.  Refitting or remodeling of an existing regular toilet into a dual one involves extra costing owing to modifications in building construction.

Cultural factors

Several cultural biases exist regarding dual flush toilets. The issue is that body waste is a such a delicate topic that culture becomes an important factor in determining change as a necessity making hands on approach to personal waste harder to accept.

However, if all of us become more open minded and embrace newer strategies of waste management like dual flush toilets, we can help reduce water shortages and pave way for more efficient water management systems.

Dual flush toilets, the answer to domestic water problems