The new legislation, signed by Governor Arnold Schwarzenegger, requires all newly fitted toilets in the state to meet efficiency standards.

Like many states in the USA, California has been hard hit by drought this year and is looking at ways to reduce its water use in the face of a growing population.

It applies to both dual and single flush loos, and is expected to save some 8 billion gallons of water each year.

The standards will be phased in from January 2010 and will require all new toilets installed or sold to be high efficiency models by 2014.

High efficiency toilets (HETs) are already widely available in California, with dual flush toilets an increasingly popular choice.

An Australian invention, where conservation has long been a daily necessity, dual flush toilets have become the worldwide standard for water efficiency.

The dual flush toilet saves even more water than a single flush HET because of the flushing options.

Two buttons on the cistern the tank release different flush volumes, one for solids and one for urine.

The dual flush option leads to greater water savings over single flush types, since the small flush is used four times more than the larger flush.

Around the world, dual flush technology has become a primary means of household water conservation, with more dual flush toilets outstripping sales of traditional single flush models.

Sam Bond

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