Since the recent triple single day power failures and subsequent removal of scores of trees in the neighborhood, many of you have asked to find the root cause of Pepco’s actions. Thankfully Pepco’s VP of operations has come back to me yesterday with his responses that I want to share with you. I do have a number of follow-up questions that I will write in another post. First, please see Pepco’s response below and let me know what you think.
On Power Outages
There were three reports of outages on July 23 — 11:38am, 4pm and 5:15pm. The causes of these outages are as follows:
1. The 11:38am outage was caused by a tree limb that fell onto a feeder. The tree was down between two poles. Asplundh located the limb and reported the matter to dispatch and the line was de-energized so that the tree removal could proceed safely.
2. The 4pm outage was the result of a broken cross arm which fell into a transmission bank and caused a small fire. The cause of the cross arm break is unknown; however, after the derecho, we continue to identify damage and make repairs to our infrastructure.
3. The 5:15pm outage was also the result of the broken cross arm.
There are many reasons that an outage can occur on a “non-storm” day, including tree limbs falling onto wires, poles hit by cars, and damaged equipment caused by a storm that has passed. I understand the frustration customers feel when an outage occurs on such days. We are investing $910 million over five years to improve reliability, but even with that investment there will always be inconveniences caused by events that are simply beyond our control.
On Tree Pruning
With respect to the tree trimming, every tree that was removed was done so with written permission of the right of way owner — the City of College Park, a private property owner, and the Parks Department, as appropriate. The State of Maryland’s Department of Natural Resources also signs off on tree removals. All pruning is done to national standards, and tree work performed on trees owned by the City is done in consultation with City staff and/or contractors.