Low-flow toilet models work as well or better than models that use up to seven gallons of water per flush. An evaluation program performed jointly between the U.S. and Canada proves how well low-flow toilets really work.
The evaluation program performed is called Maximum Performance and uses soybean paste encased in latex to show how well low-flow toilets work. These test results can be found easily on the Internet. There are low-flow models with dual-flush capability. These models offer separate flush modes for liquid and solid waste. The performance difference in switching from a standard toilet to a low-flow toilet is a savings of potentially 1,000 gallons of water a year.