Science Society Picture Library / Getty Images file

A 400-watt, high-pressure sodium lamp.

A Connecticut woman managed to recoup almost $10,500 after her utility company acknowledged she had been erroneously billed for two street lights in the subdivision where she lived for 25 years, according to a ratepayer advocate in the state.

Her story is an object lesson in the value of studying the fine print.

Before Grace Edwards’ husband bought the house in 1987, it was owned by a developer who was paying the cost of the street lights intentionally, but for some reason the costs were never removed from the bill, according to a release by Office of Consumer Counsel, Connecticut's ratepayer advocate.

Each month there were two mysterious items on her Connecticut Light and Power bill worth about $20: "9500 Lumen HP Sodium" and "6300 Lumen HP Sodium," according to a report in the Hartford Courant.

"It (had) no more relevance to me than any other line items on the bill," she told the Courant.

She figured out what the bill meant only when a prospective buyer of her home requested a history of utility costs, and the records sent by CL&P were lower than what she actually paid. When she queried CL&P, a representative told her the difference was the cost of the street lights, the report said.

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At first, CL&P agreed to remove the charges from her bill, but not to reimburse her, the Office of Consumer Counsel release said.

"I called CL&P, wrote letters, did it all, but they were unresponsive to any kind of reimbursement," Edwards said, according to the release. “I really thought I was going to have to sue CL&P."

The Public Utilities Regulatory Authority was dismissive and rude, according to her account in the Courant report.

Edwards persisted, with the help of advocates at the Office of Consumer Counsel. Ultimately CL&P admitted it was at fault.

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On Friday, Edwards received a check from CL&P for $10,491.21 — about $5,800 of it for overpayment and the rest for 25 years' worth of interest. She also got an apology.

"Mrs. Edwards received service that is below our standards and we have apologized to her for the error and the inconvenience," CL&P said in a statement sent by media contact Mitch Gross. "We have reimbursed her in the amount that she was incorrectly billed plus interest, and will be using this case as a learning experience to identify process and customer service improvements to be sure this doesn’t happen again in the future."

Gross declined to answer other questions except to say: "This should not have reached this point."

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