The City of San Diego had a system in place to warn-water meter readers of inaccurate or questionable reads on manually read meters.
But somehow more than 300 residents in four neighborhoods - Rancho Bernardo, Mira Mesa, Rancho Penasquitos, and Carmel Valley - were still overcharged by an average $300 on recent bills. Their meters were all the manually read type.
Meanwhile, residents from Webster to Normal Heights to La Jolla are still questioning the validity of mysteriously high bills.
"At this point I don't trust the government. Who is overseeing these departments?" Carmel Valley resident Denise Hornby said in a recent interview over her $1,800 water bill.
The city has more than 250,000 water meters that need to be read manually. Workers use a handheld electronic device to enter the readings, and get a warning if the numbers don't fall inline with that meter's use from the last billing cycle, said Steven Broyles, a city meter reader of about 18 years.
"Based on the pervious use 60 days ago, it was inline," Broyles said after measuring a home in Rancho Bernardo. "So it didn't throw me a failed audit."
Workers, however, are able to override the warning and enter the reading.
If that happens, the city says the meter's data gets kicked into the city's quality assurance process - a process that could have uncovered the pattern of errors in those four neighborhoods. The city terminated the employee who made the errors that lead to the 300 erroneous bills.
A city spokesman, however, declined to comment on whether the system lead to the discovery.
The city auditory, meanwhile, is continuing a top-down probe into the water billing department. Results are expected in June.