Installing utility lines underground comes with a very high price tag, coupled with more difficult (and longer) repairs in the event of a power failure. Also, converting an overhead system to underground may do more damage to the root systems of existing trees.
While we attempt to preserve the aesthetic value of trees and vegetation in and around our facilities, during outage situations our primary concerns are reducing fire and electrocution hazards, and providing personal and public safety from falling branches and trees. Following these events, some trees may require additional pruning to meet industry standards.