Post Outage Autopsies/ Root Cause Analysis

Many utilities approach vegetation management by seeking to establish and maintain a corridor around facilities. Although this approach may be visually satisfying to the utility manager, research has shown that significant expense is incurred pruning and removing trees that had a very low risk of causing electric service interruptions. For more information on reliability-centered maintenance, please click here.

One of the most important components of an optimized vegetation management program is to objectively understand how trees cause outages on YOUR system. Accomplishing this requires the utilization of post outage autopsies or the root cause analysis of incidents where trees caused outages.

This process takes discipline, but the costs and efforts are exceedingly low when compared to the cost and effort associated with executing tree pruning and removal work. It could be argued that no process will have a greater effect on a program than having a solid understand of the impact of trees. This process also enables the utility to quickly and confidently respond to inquiries from external stakeholders, including regulatory agencies.

ECI can not only assist utilities with developing processes to successfully execute post outage autopsies and root cause analysis, but we can also provide trained personnel to conduct this work. We can also perform the analysis of the data to objectively:

• Establish field work guidelines, focusing on high-risk combinations of vegetation and conductors
• Define work methodologies
• Hold contractor accountable for completed work (e.g., mitigation of trees that have an unacceptable risk of failing)
• Respond to utility commission or board inquiries into storm events or major outage events
• Demonstrate to insurance carriers that your vegetation management program is effective
• Provide objective data for resource allocation purposes
• Enable a distinction to be made between those outages that could have been prevented by the program, and those that could not (e.g., trees failing far from the right-of-way that had no obvious signs of defect)