LOS ANGELES (CBS/AP) — The Los Angeles Department of Water and Power has spent nearly $100 million on a new computerized billing system that has overcharged customers and sparked a flood of complaints.

The agency on Friday estimated the cost of software, hardware, staff time and outside vendors/consultants to be about $98.94 million. An additional $8 million was approved for Post-go-live costs but because that money was not spent, it was not included in the $98 million total.

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Another $63.1 million will be spent on internal labor costs, but the LADWP said that money would have been spent anyway on other department projects, IT and customer service operations.

Since the system launched in September, the DWP says 3 to 5 percent of its 1.4 million customers have experienced incorrect bills, delayed bills and late notices. The agency also was swamped with complaints and many callers complained of being stuck on hold for too long — sometimes for an hour.

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The LADWP says it will roll out a system next week that allows customers to get a call back instead of waiting.

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