Power has been restored to all 22,000 Clay Electric customers who lost it for a short time Wednesday.
Derick Thomas, director of member and public relations, said crews found a broken transmission insulator at the brickyard substation. They were able to replace it just after noon, allowing the final 6,000 customers' power to be turned back on.
All the other substations had power restored shortly before.
The insulator was likely cracked, possibly due to a lightning strike, officials said. The heavy rainfall that occurred Wednesday likely seeped into the cracked insulator and caused it to lose its insulating quality, leading to the fault, officials said.
The circuits shut down when the fault occurred in order to protect the system from damage.
The brickyard substation serves the northern portion of the Doctors Inlet area in Orange Park.