Underground transformer fire knocks out power in downtown Chattanooga

What happened

A fire and explosion in an electrical vault near Broad Street and Aquarium Way in downtown Chattanooga, Tennessee, knocked out power for about 500 customers on the evening of Tuesday 14 June 2022. A co-owner of Mellow Mushroom said staff and customers were evacuated after they saw flames and heard crackling from the grates and a manhole on the sidewalk. The Chattanooga Fire Department (CFD) responded quickly. The transformer that caught fire was too hot for repairs to begin immediately.

EPB, the local utility, said a cause had not been determined, and that no cause had been identified when asked whether record-high temperatures could have contributed. Power was restored after about 12 hours for most affected customers. EPB said Ben and Jerry's was the only business still without power and hoped to restore it late the following night. Local businesses, including Ben and Jerry's and Mellow Mushroom, worked to save perishable stock, with help from the Downtown Alliance.

Contributing factors

No cause had been determined at the time of reporting. EPB said no cause had been identified when asked whether record-high temperatures contributed.

Lessons learned

1. Underground and vault-mounted transformers need thermal monitoring and periodic inspection, because a fault in a confined space can escalate quickly and may be visible only through grates and manholes.
2. Utilities should plan repair access for overheated equipment, since a transformer that is too hot to work on delays restoration.
3. Businesses that depend on refrigerated stock in areas served by urban underground networks should plan for backup cooling and for rapid stock relocation during extended outages.

More lessons on worker safety and safe systems of work, outages, backup supply and restoration, from every incident on the register.

Source

newschannel9.com