Rebuilding Reliability: Lessons From the Ice Storm of 1994

This year marks the thirtieth anniversary of the Ice Storm of 1994, a weather event deemed by many here in Delaware as a “once in a century storm.” At DEC, its impact was felt heavily by our crews working to restore power as well as our members eagerly awaiting the return of their electricity. For over ten days, Co-op employees, with the help of other local lineworker teams and crews from several neighboring states, braved the difficult and dangerous icy conditions to get the lights — and more importantly, the heat — back on. 

At the height of the storm, DEC was faced with replacing roughly 500 broken poles and the repair of nine substations and 40 lost circuits. Combined, the damages resulted in lost power to 40,000 members across the Co-op’s service territory, and between $2,000,000 and $3,000,000 worth of damage to the DEC system. In the 1990s, the standard time required to replace a broken pole was around four hours. Given that much of the Co-op’s electrical equipment was encased under one to three inches of solid ice, the process took considerably longer, with most crews working 16-hour days to get the job done. Even then, reoccurring outages caused by trees falling on the lines, as well as poles breaking under the weight of the ice or due to car accidents, delayed restoration efforts further. Needless to say, when the final members without power were restored on February 19, everyone affected by the ice storm enjoyed a well-deserved sigh of relief. 

While the initial job of restoring power was complete, it was now time for the Co-op to begin the work of rebuilding its system. As much as anything, the storm had proven to be an educational experience, and with its hard-won lessons learned, DEC started laying the groundwork for record-reliability.                                                                    

Today, the Co-op uses innovative technology like Distribution Automation (DA) to minimize outages by identifying and isolating issues on the lines. Once DA has isolated the cause of an outage, it can begin redirecting electrical load by backfeeding from surrounding substations to reduce the amount of time members are without power and significantly reduce the number of members initially affected. As of this month, DEC has successfully outfitted all of its substations with DA technology. The addition of new substations on Co-op lines, as well as updating existing substations with new transformers, enables DEC to continue to provide reliable electricity to its expanding membership. Substations facilitate reliable electric service by providing more opportunities to backfeed power on the system when necessary, alleviating the strain on the lines. 

As for the lines themselves, the Co-op ensures the stability of utility poles and equipment through a regular inspection program. Using thermal and infrared technology, electrical equipment is examined for “hotspots” — areas that could represent structural issues — and replaced when necessary. DEC also operates a vegetation management program that routinely monitors areas of our system to determine when trees and foliage need to be trimmed back around lines to prevent future outages before they even occur.

 Just as it did in the aftermath of the Ice Storm of 1994, the Co-op continues to develop and utilize innovative programs and technology to strengthen and grow the reliable system members have come to know.