Arizona is No. 2 two in the nation for certain water-efficient showerheads and bathroom faucets. But the state is further behind when it comes to toilets.

A new survey compares how prevalent WaterSense products are in the country. WaterSense is a label from the federal Environmental Protection Agency that signifies a certain level of water efficiency for a given fixture.

More specifically, a WaterSense label is meant to indicate: 

• A toilet of 1.28 gallons per flush or less.
• A bathroom faucet of 1.5 gallons per minute or less.
• A showerhead of 2 gpm or less. 

These are stricter than the required federal standards of 1.6 gallons per flush, 2.2 gallons per minute, and 2.5 gallons per minute, respectively. 

Older toilets can use much higher amounts of water. The report says replacing these inefficient toilets alone would save “approximately 520 billion gallons of water — roughly the amount of water that flows over Niagara Falls in about 12 days.”

The survey pegs 16.7% of Arizona toilets as WaterSense, almost the same as the national average of 16.8%. Nine states, including California (21%) and Texas (25.8%), have higher rates than Arizona of market penetration of WaterSense toilets.

According to a representative of GMP Research Inc., the firm that conducted the study, those states did not see their new home construction slow as much as Arizona’s during the Great Recession. 

“The other states did not suffer as bad as Arizona did, and that would explain the difference,” said Victor Post, Vice President and Managing Partner of GMP Research. 

Toilets typically have a thirty year lifespan, according to the study. The lifespan of a bathroom faucet is 15 years and showerheads typically last 12 years. Arizona had a much higher market penetration rate for those fixtures than for toilets.

Some of the states in the survey require installers to use WaterSense products for new or existing homes. Georgia, for example, requires all construction to use WaterSense-level toilets and bathroom faucets.

The city of Scottsdale mandates the same flush and flow rates as WaterSense for fixtures installed in brand-new homes and commercial buildings. That is unique among the 10 Valley cities who are members of the Arizona Municipal Water Users Association.

“The most surprising [thing] to me was that not many municipalities and water utilities are promoting these products with special rebates,” Post said. “Now in Arizona, Scottsdale is. But the City of Scottsdale is not Arizona.”

Scottsdale, Avondale, Gilbert, Chandler and Tucson offer rebates for installing WaterSense fixtures, according to the EPA.

The study was funded by the industry group Plumbing Manufacturers International. CEO Kerry Stackpole said the goal was to show how much “run room” there is in the market for these water-efficient products, as well as the amount of water that could be saved.

“Does it bring business to our members [if] a consumer decides to install a low-flow toilet? Sure,” said Stackpole. “At the end of the day, our goal is really to make sure that we’re delivering safe, responsible plumbing in a way that does benefit not only the consumer, who saves money, frankly, but does [a] good thing for society at large.”