The News Journal reports county Chief Financial Officer Mike Coupe now estimates that the errors in bills totaled $675,000. That's higher than the $500,000 estimate Auditor Bob Wasserbach gave officials in July.
The problem started when Artesian switched from a quarterly to a monthly billing system last year. Sewer bills are calculated based on water consumption.
Coupe says 21,347 residential customers were overbilled and another 6,957 customers were underbilled for a total of $218,000. About 20,000 customers' bills were accurate.
Wasserbach said in July that county officials knew about the problem in December, but decided to only take action if they got complaints.
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