DWP Power Outage Details & Update
For Immediate Release
October 30, 2017
DWP POWER OUTAGE DETAILS & UPDATE
CORONA, CA– Corona’s Department of Water and Power (DWP) experienced a significant power outage on Friday, October 27, 2017, that left the Dos Lagos communities, the Shops at Dos Lagos and the Crossings shopping center without power for approximately 11 hours.
The outage was a result of a problem with Southern California Edison’s (Edison) main 33kV feeders that provide Corona’s delivery of wholesale power. At approximately 4 p.m., the distribution system experienced a fault on the Interpace 33kV connection that affected areas of Lake Mathews and south Corona. The outage was traced back to a faulty pothead connection on a 750 CLP cable.
Edison dispatched Troublemen (TM) to the area who immediately began assessing the issue and restoring power by switching Corona to another feed source. At approximately 6 p.m., Corona was switched to the OWENS’ 33kV line and power was restored temporarily.
The impact of the outage was compounded further by the fact that at approximately 6:23 p.m., the OWENS 33kV system flashed and failed due to a failed connection of a switch on an overhead pole near the intersection of Cajalco Road and Temescal Canyon Road. The connection failure caused the wires near the substation to twist and tangle together causing the need for further isolation of the OWENS’ line.
With two critical pieces of infrastructure impacted, Edison crews decided that the quickest way to restore power was to fix the broken connectors on the Owens 33kV outage as replacing underground cable from the Interpace 33kV outage would take substantially longer. SCE crews inspected the switch and determined that additional safety precautions were needed; switching was performed to isolate the system and repairs were made. After the completion of the repairs on the OWENS’ 33kV system switching was performed to bring all customers back online at approximately 3 a.m.
An additional outage was performed early Monday morning between 4 a.m. and 5:30 a.m. to repair the damaged cable on the Interpace 33kV. This outage was deemed an emergency repair that needed to be completed to prevent any further damage from occurring.
“We are actively working cooperatively with Edison to address all service and distribution related issues for this area,” said Corona DWP General Manager Tom Moody. “It is with these efforts that we hope to resolve these outage issues and increase reliability to the area with near and long-term solutions.”
Edison’s upcoming action items include reviewing insulators and putting together a plan to get them fixed as soon as possible; having a field engineering team is working on TDRL logic for automation; and the temporary switching is being reviewed to split the Dos Lagos and Crossings between the Owens and Interpace 33kV circuits.
Corona Department of Water & Power