The deadliest-ever California wildfire may have been caused by a faulty wire overdue for a replacement

For five years, PG&E Corp. PCG -3.89% repeatedly delayed a safety overhaul of a century-old high-voltage transmission line that is a prime suspect behind the deadliest wildfire in California history.





The company told federal regulators in 2013 it planned to replace many of the towers, wires and hardware pieces on the line, called the Caribou-Palermo, regulatory filings show. It again proposed the project in 2014, 2015 and 2016—pushing it back each year. The company planned to start work June 2018 and finish late last year. It hasn’t begun.





On Nov. 8, 2018, winds picked up before sunrise near Paradise, Calif., when a wire snapped free from the Caribou-Palermo line, creating an electric arc that scorched the metal tower supporting it. A few minutes later, a PG&E worker spotted a quarter-acre fire under the line, the company has disclosed. Within hours, what became known as the Camp Fire destroyed Paradise and killed 85 people. California fire investigators haven’t yet determined the fire’s cause.