Cable fault blamed for power outage

The power outage that occurred in Boulder City late last week was the result of a faulted cable and not the delayed installation of the new transformer, according to a city official.

The outage, which began at 4 p.m. Friday, Sept. 20, and lasted until 5:15 a.m. Saturday, Sept. 21, affected 200 homes on Georgia Avenue, Christina Drive, Darlene Way, Jeri Lane, Capri Drive and Sandra Drive.

Boulder City’s Electrical Distribution Supervisor Marvis E. Poole said it was caused by a faulted primary cable that caused more stress to other equipment and parts of the electrical system.

“The fault current at the time of this failure was great, causing stress to weaker parts of the electrical infrastructure in that area. There does exist a current redundancy to the electrical system. … However because there were multiple stresses to the system, each location and switching point had to be tested and verified,” he said. “Some of which proved to be inaccurate in our mapping system. This added to the length of outage.”

A cable fault, which causes a short, happens when a power cable deteriorates so that it can no longer contain the electrical current.

Poole said the electric division is in the process of remapping the entire grid to fix the deficiencies found during the power outage.

Additionally, he said this outage was not caused by the delay in the installation of the city’s new backup transformer, which was delivered in April 2018.

“The addition of this new transformer to the electrical system would not have prevented the outage on Sept. 20, as it has no bearing on the city’s electrical infrastructure,” Poole said. “It is a source of power to the entire overall system.”

Several months after the new transformer was delivered, a leaky part was discovered, which pushed its installation to October to avoid the hot summer months.

The new transformer cost approximately $1.1 million, and this delay has not caused an increase to the project.

Contact reporter Celia Shortt Goodyear at cgoodyear@bouldercityreview.com or at 702-586-9401. Follow her on Twitter @csgoodyear.