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Water Saving Toilets
October 27, 2009
Water-saving toilets are now standard on all new construction because of a 1992
federal mandate for plumbing fixture manufacturers. Also known as low-flow toilets,
water-saving toilets use 1.6 gallons per flush (gpf) of water or less, compared
with older toilets that use 3.5, 5.0, and up to 7.0 gpf. The 1.6 gpf models significantly
reduce the amount of fresh water consumed and the corresponding amount of blackwater
generated. For example, using a 1.0 to 1.6 gpf toilet instead of 3.5 gpf models
cuts indoor water use by more than 15%; when used instead of a 5.0 gpf toilet, it
cuts water use by 20—25%.
Performance and Standards
The earliest models of water-saving toilets were introduced in the 1970s. Some have
been notoriously poor performers, requiring multiple flushes to remove waste completely.
Often, these early models were not engineered specifically to use less water, but
were simply modifications to existing conventional toilet designs. By contrast,
high performing low-flow toilets currently available are engineered to use less
water and use it more powerfully. Today's high-performing models do remove waste
as efficiently, or more efficiently, than conventional toilets while using much
WaterSense has recently announced the first product specification that covers high-efficiency
toilets (HETs)—those that use 1.28 gallons per flush (gpf) or less. WaterSense (www.epa.gov/watersense)
is a voluntary public-private partnership program sponsored by the U.S. Environmental
Protection Agency (EPA). With the announcement of the final HET specification, manufacturers,
retailers, and distributors of water-efficient plumbing fixtures can use third-party
certification to gain permission to use the WaterSense label on their products.
In time, consumers will be able to recognize products with the WaterSense label
as quality and high-performing water savers.
A variety of high-performing, low-flow toilets is available for residential use.
Using different technologies, they provide a clean, efficient flush while meeting
the 1.6 gpf maximum.