Storm Resiliency Study
Weather events in the Northeastern United States in 2011 and 2012 resulted in significant challenges for the electric utility companies serving the affected areas. Named storms Irene, Lee, and Sandy, along with the October 2011 ice storm and more routine storms, resulted in significant utility infrastructure damage. Hurricane Sandy had unprecedented impacts on utility operations. These events have driven internal reviews by utility companies of their level of preparedness for major events and their ability to respond to such events. Preparedness reviews include consideration of the various infrastructure options that could be pursued to mitigate the risk of infrastructure damage from future extreme weather events.
Transmission systems for many utilities throughout the United States were originally designed and installed prior to the current standards developed by The American Society of Civil Engineers, ASCE 10, 74, IEC 60826, and NESC that govern the design of transmission lines today.
This project was an evaluation of the present ability and future needs of the Client’s Transmission facilities to withstand extreme weather events, as determined by Federal Emergency Management Agency (FEMA) and the U.S. Army Corp of Engineer’s Cold Regions Research and Engineering Lab (CRREL). Quanta Technology and Realtime Utility Engineers, Inc. (RUE) were engaged to evaluate existing standards and review recorded weather events. The team worked together to provide detailed reports which addressed specific recommendations for remediation and upgrades of existing structures, as well as the design of future facilities.
The specific objective of this project was to review the existing transmission facilities to identify potential extreme weather risks. These risks were based on historical events and predictions of future climate changes that may result in more extreme conditions. This evaluation was also completed to further determine where any particular facility was in its life cycle, to suggest potential upgrade options or replacement objectives for several existing facilities.
Sophisticated structural analysis programs such as PLSCADD, STAAD, and RISA were all used to check historic performance against current codes and other extreme loading cases, such as a broken conductors or heavy ice and wind conditions. This type of analysis provided information on the structure loading under various conditions, which was then used in to define risk of structure and component failures, along with develop predictive maintenance and upgrade schedules for structures under the new load conditions that were developed.