Bellagio power outage tied to material failure

Tuesday, May 25, 2004 | 10:40 a.m.

A county investigation into the power failure that shut down the Bellagio for more than three days and led to the displacement of thousands of customers and employees last month hasn't turned up an explanation for what caused material to degrade, leading to the failure, the county's top building official said.

In a memo circulated this month, county engineers said the power outage was caused by a degradation of material used to connect the power cables that run alongside the resort.

Similar to wires that are held together by plastic clips, major power conducting cables are held together by a "cone splice," Clark County Development Services Building Division Director Ron Lynn said.

"The failure is believed to be caused by material degradation (of the cone splice) over a period of time," Lynn said.

The exact cause of the degradation is still unknown, however, he said.

No standing water was visible in the vault where the cable failure occurred, though weather changes such as an increase in humidity could have damaged the connecting material by causing it to expand and contract, he said.

County officials don't believe the failure was caused by an overt defect in the material or human tampering after it was installed, he added.

The county has no intention of pursuing its investigation further because officials believe no building codes were violated in the incident and there is no need to alter building codes as a result, Lynn said.

The county is ultimately charged with enforcing building codes, he said.

"It's not incumbent upon us to go to the expense of a spectral analysis to analyze material at that kind of molecular level" to help determine a cause, he said.

"This is not a criminal investigation ... in the absence of further information, we're satisfied with the results," he said.

County building officials and MGM MIRAGE executives are still awaiting the outcome of an independent report conducted by forensic engineers at the request of the county.

"It may be more detailed. It may say the same thing," Lynn said of the upcoming report. "I have no expectations either way whatsoever."

MGM MIRAGE spokesman Alan Feldman said the company hasn't determined the cause of the failure and is waiting on the independent report, which could be complete within a month.

The cable system met code requirements and passed several inspections, including an inspection about a year ago of electrical cables that were rerouted to allow for the construction of the Bellagio's new room tower, Lynn said.

The power failure occurred after some main power cables shorted in a vault, causing overheating in the vault that damaged neighboring power lines and took out the resort's main power source, according to county and resort officials. In order to repair the lines, resort engineers cut power to the remaining circuits in the vault.