When it comes to municipal utility bills, which cost the city of San Diego about $50 million a year, taxpayers can't be sure they're getting all the “bang for the buck” they could.
The City is one of San Diego Gas & Electric’s biggest customers, and many dollars could fall through the cracks.
Its auditors say there aren't enough internal control programs to reliably catch incorrect billings or rate categories.
San Diego's utility accounts number more than 3,500 and cover 1,600 properties, from City Hall and other buildings to 60,000 street lights and traffic signals at some 1,500 intersections.
Auditors have now discovered that among accounts recommended for study by SDG&E, 40 percent actually qualified for cheaper rate categories.
The company recently gave the city a $1.7 million credit for overcharging on meters at a sewage station.
To get the lowest possible rates and reduce the number of overpayments, city departments were advised to upgrade their training, monitoring and analysis of utility invoices.
“We made three recommendations to improve the process,” City Auditor Eduardo Luna, told NBC 7 in an interview Wednesday. “Management agreed to implement all three recommendations, and I think they came up with a timetable that's going to work for them. They're taking steps to try to resolve those, hopefully next year."
The audit originally began with a look at street light bills, and then went system-wide.
"We realized that there were bigger issues with how the city was processing the utility payments, how they were reviewing the invoices,” Luna explained. “And we decided to expand it and try to get a little efficiency on our part and make some comprehensive recommendations."
Energy-saving moves already have lowered projections for the city's utility costs -- among them, replacing 14,000 street lights with LED lamps this summer.