Some in the town known as 'The Peak of Good Living' are getting bills equivalent to a mortgage payment.
More than $1,800 was drafted out of Kurt Dusterberg's account.
"It's a little alarming when your normal bill is around $250 bucks," he said. "My water consumption over a two-month period went up about 15 to 20 times."
Others have experienced similar sticker shock and now are questioning how they can handle a huge bill.
"I have to make ends meet, so it's going to be a little bit of a struggle," said resident Virginia Wood.
Gilbert is speaking for the first time to talk about July's cyberattack.
"It's been very difficult. It's been challenging for our entire town," said Gilbert.
He says staff members are reviewing bills with discrepancies and accounts will be credited if there's an error.
"It's a long process," said Gilbert. "I want to encourage our residents to speak out, come into the Town Hall, and just don't take that for granted. If you think there's a problem with your bill, please come into our town hall, speak with one of our customer service representatives."
ABC11 asked if the town's own bookkeeping has been compromised during the attack.
"We don't know that just yet. Our plan is to have a third party come in and review all of the information to make sure that we do get it right," said Gilbert.
People, who are set up on auto draft to pay utility bill, are being instructed to cancel that service until further notice.
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