Giving New Life to Aging Underground Electrical Vaults

SCE implements innovative process to repair decades-old vaults quickly and safely, helping to reduce #power outages and traffic disruptions.
Chip Chapella has been with Southern California Edison for almost 40 years. His job involves repairing underground electrical vaults that have been in service much longer, often by 20 years or more. These concrete boxes house electrical equipment for the underground portion of the local grid and contain transformers and other key components that help sustain a reliable power system.
Traditionally, vaults approaching the end of their life cycle need to be replaced because of cracks or other damage that could compromise the integrity of the equipment inside. That involves digging out the vault, often among newer buildings and other infrastructure.
“A vault constructed in the 1960s might have had a few buildings in its vicinity at the time,” said Chapella, SCE’s vault replacement program manager. “Today, the same structure might be adjacent to multiple large buildings on a very busy street with other utilities underground. It is a complex and challenging process to go in there to dig out the vault.”
More than 20,000 underground vaults in SCE's service area may be eligible for the Composites for Infrastructure repair process.
Replacing an entire vault can take about 30 days and result in extensive traffic disruptions and lengthy power outages. But now, Chapella’s crew is using an innovative process developed by a company called Composites for Infrastructure that takes a fraction of the time. SCE is the first electric utility to deploy this technology, which was initially developed to patch up and strengthen dams.
Recently, Chapella’s team used the process to repair a vault on the Balboa Peninsula in Newport Beach. A fiberglass and liquid-based compound is applied to the interior walls of the vault, filling and sealing cracks. When the substance hardens, it’s stronger than the original concrete.
The Balboa Peninsula in Newport Beach, where SCE recently used the Composites for Infrastructure process to quickly repair an aging underground #electrical vault.
“The value of this work is that you do not have to excavate,” Chapella said. “You don’t get frustrated drivers because you are digging up the roadway, and your construction time is reduced from about 30 days to one week.”
“I’m happy Southern California Edison is using this new process. We have significant concerns about traffic on Balboa Peninsula, and any time you can reduce delays for our residents, that’s a good thing,” said Diane Dixon, Newport Beach mayor and a newly elected member of the California Assembly. “I’m also encouraged that SCE is being proactive in replacing its aging infrastructure and reducing the duration of power outages, which are a significant inconvenience for our residents.”
The Composites for Infrastructure repair is expected to extend the life of an underground electrical vault by 50 years.
Another important aspect of the new vault repair process is its cost savings. Without the intrusive excavations and the significantly shortened work time, the cost is 35%-45% cheaper than a vault replacement.
With more than 20,000 vaults eligible for the process, the savings to customers start to add up.
“It’s a win-win for everyone,” said Chapella. “Businesses and residents are happy because we’ll roll out of a project in one week. Customers will be happy as we pass these savings on to them over the coming years.”
#safety