Southern California Edison has undertaken a series of actions to address shortcomings in the operation of the downtown Long Beach underground power network that led to two extended outages last summer.
Corrective measures are being implemented based on the findings and recommendations in SCE’s own internal investigation of the two outages and a separate independent analysis by Maryland-based Davies Consulting LLC, an expert on utility risk assessment and management.
The two reports found a cascade of events combined to cause power outages that hit downtown Long Beach from July 15-20 and July 30-Aug. 3. A series of operational shortcomings combined to exacerbate the initial equipment failure and contributed to the severity of the outages.
“SCE is deeply disappointed with the issues that were discovered,” said Pete Dietrich, SCE’s senior vice president of Transmission and Distribution. “We are encouraged that the investigations have identified issues that are correctable, that we will learn from them and that can help us improve the way we manage the network to provide the kind of service our customers should expect from us.”
The July 15 outage began with the failure of an underground cable splice that caused two circuits in downtown Long Beach to shut down. SCE was unable to determine the cause of the splice failure. The July 30 incident resulted from stress on the equipment due to the impact of the July 15 outage.
Repairs began immediately after the outages and will continue over coming months. The work ranges from ensuring all required equipment in the underground power network is in place and in operational condition to providing additional staff training and network oversight.
A separate investigation of the outages by the California Public Utilities Commission is pending.
Dietrich discusses the report’s findings below.
What has been the performance of the network since the incident? Is the system working well and safely?
The system has performed well since we completed repairs on it after the outages in July. Reliability and performance for the downtown networked system has returned to the levels we had prior to the incident and compares favorably with overall SCE territory-wide reliability in the region.
What corrections have you completed since the incident? Status of repairs? Tethering?
The inspection work after the incidents was safely completed and some issues — none major — were addressed on the downtown network system and additional inspections on other parts of the grid in Long Beach are ongoing per standard protocols.
- We have inspected all vaults in the affected downtown area.
- We have conducted testing on all network protectors and relays. We also performed and continue performing inspections on substation equipment and should complete that process by the end of November.
- We have updated the network maps to reflect the improvements made during and after the two events, and the current configuration of cables and equipment.
- We have completed installation of automation devices on the balance of the network protectors. Modeling of the network is ongoing and will provide additional data points to ensure the network is operating properly.
- The enclosure lids for the downtown Long Beach network are now tethered as a means to better ensure public safety. This was an enhanced safety measure taken due to the uniqueness of the downtown network system.
What has been the outcome of the bill credits and claims that you have provided to Long Beach businesses and residents?
SCE has worked diligently to provide bill credits for residents and business owners impacted by the incident. The vast majority of claims expected from the incident have been received and processed, though we may see some additional claims.
As part of that effort, SCE has paid out more than $1.8 million in claims and bill credits thus far.
Was SCE to blame for the outages that took place in Long Beach?
The findings of both SCE’s internal and the independent investigation point to shortcomings in SCE’s management of the network.
SCE is deeply disappointed with the issues that were discovered and we are already working to address the issues identified in the findings and ensure that the management of the network is at the level necessary for the network to operate safely and efficiently for many decades to come.
We are encouraged that the investigations have identified issues that are correctable, that we will learn from and that can help us improve the way we manage the network to provide the kind of service to our customers they have come to expect from us.
What are the key findings? Do the reports both agree on the causes?
While the two investigations were conducted by different teams (one internal and one external) and have separate perspectives, the two reports coincide in their findings that the incidents resulted from lack of adequate management oversight of the downtown network system.
The reports both found a lack of “ownership” of the network by a single entity within SCE, the need for more thorough protocols in the operation of the network, as well as the lack of trained staff dedicated to understanding and managing the system.
The reports agree that had SCE addressed these issues, it may have served to prevent the causes of the cascading events and the resulting damage to the system.
The reports found deficiencies in maintaining the knowledge base on the configuration and operation of the system and a lack of sophisticated controls needed to more efficiently and effectively prevent and respond to the cascading events that occurred.