The most outrageous water bills in DeKalb County — those that overcharge residents by thousands of dollars — are caused by programming errors that sometimes mistakenly multiply consumption by 100, DeKalb CEO Mike Thurmond told residents Tuesday in an update on the ongoing issue.

The error, which turns a $100 bill into a $10,000 bill, is limited to about 200 accounts, but it shows the depth of the county's problems with water billing, Thurmond said. Thousands of other customers have faced inexplicable bills because of malfunctioning metersinaccurate meter readings and data entry errors.

He says this is a system-wide problem that won't be fixed overnight.

“If you crystallize the dysfunction and inefficiency that has plagued our system, if you distill it, it’s capsulized in those (200 accounts),” Thurmond said of the multiplication mistake. “The good news tonight is that I am confident that we have been able to identify the source of this embarrassing problem.”

Thurmond spoke to about 75 people gathered at Rehoboth Baptist Church in Tucker for his second community meeting on short-term efforts to reduce the number of inaccurate bills.

But he acknowledged it will take two or three years to completely fix the problem by replacing meters countywide, upgrade computer systems and improve customer service. He said the number of calls to customer service representatives has declined by 55 percent since last fall.

“These problems did not appear overnight. It will take persistence over a period of time to unravel,” Thurmond said. “We are continuing to make significant steps in the right direction.”

But several residents struggling with high water and sewer charges said they're find themselves frustrated as they try to resolve their problems.

Dan Daugherty, who lives near Northlake Mall, said he can’t even find water meters at his condo complex, and customer service representatives were unhelpful.

“We’re not seeing any satisfaction, and we just give up,” he told Thurmond.

Many people whose bills have been withheld by the county worry that they'll face substantial cumulative charges when they do eventually receive a correct water bill, said Linda Dacey-Caban of Decatur.

“When we do get a bill, how do you expect people to pay these monstrosity bills?” asked Dacey-Caban, who hasn’t been billed since November.

Thurmond said customers won’t be penalized, and payment plans without late fees will be offered when requested.

He said the county is improving.

The number of residents disputing their accounts has declined by nearly 70 percent since November, from 1,993 to 621.

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