Some homeowners in Fountain Hills are angry and they want answers.
They want to know why their water bill this month has shot up hundreds of dollars.
Andrea Sobotka makes sure not to leave any faucets running, over water the grass, or empty the pool while her parents are away for the summer.
So you can imagine the shock at seeing this month's water bill for their house in Fountain Hills.
She said that her parents' average bill is around $70.
However, this month's bill from the Chaparral City Water Company was $521.
"It's not just the amount, it's the usage," said Sobotka. "It spiked to 104,000 gallons of water. That could fill 10 swimming pools. The water would have to go somewhere, it's got to be seen running down the street."
Staci Valentino showed CBS5 a Fountain Hills Facebook page where more than 40 people have complained that their water bill jumped a ridiculous amount this month.
Valentino's water bill increased from $175 to $276.
"That just seems a little strange that there would be so many of us having the same usage jumpage, and extraordinarily high bills," said Valentino. "And we're all told the same thing - that there must be a leak."
CBS5 reached out to EPCOR, which owns Chapparal Water, to get some answers.
A company spokesperson said that a recent rate hike went into effect on July 1, pushing everyone's water bill up an average of 22 percent.
But what about customers like Sobotka, who's bill spiked more than 700 percent?
Shawn Bradford is director of operations for EPCOR.
He said that there doesn't appear to be any mistakes on their end and their meters are working properly.
"No, we're not aware of any problems in our system," said Bradford. "All of our meters are read on a monthly basis. If a customer has a problem with their bill, specifically, we just encourage them to contact us and we can walk through the issues."
Bradford said that an increase in someone's water bill is often caused by an outside irrigation problem.
However, Sobotka and Valentino both said that they did thorough inspections around their homes, and could not find any leaks.
"We've never used that much water," said Valentino. "Nothing has changed in our household, so it just seems very suspect."
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