Toilets of the yesteryear used almost 3 to 5 gallons of water per flush which resulted in large water bills every month. As per the EPA guidelines, latest toilets cannot use more than 1.6 gallons of water in a single flush. This rule has compelled toilet manufacturers to come up with innovative flushing techniques such as double cyclone and WaterSense that can cut down on water usage very effectively.
Dual flush toilets are a boon as well since their low flush can take care of most of the light wastes with just 1 gallon of water. If your house does not see a lot of toilet activities then using a dual flush can result in amazing reduction in the water bills. Most of the leading brands such as American Standard and TOTO have toilets that use very low amounts of water for flushing. So grab the one you like and save some money.