Cause of O'Hare outage under investigation

Investigators remained at O'Hare International Airport late Tuesday morning trying to determine what caused three of the airport's four terminals to lose power for about 20 minutes Monday afternoon, officials said.

TSA spokeswoman Carrie Harmon said the agency's O'Hare checkpoint screening operations were shut down for about 20 minutes due to the outage.

“As soon as power came back on, we worked quickly to get equipment back up and to resume screening passengers,” she said.

According to the Chicago Department of Aviation, flights were not affected by the outage.

The airport reported the power outage at terminals 2, 3 and 5 at 3:54 p.m. Monday, and was back up at 4:14 p.m., according to ComEd.

“There are miles and miles of cables that service O'Hare so it is taking some time to investigate,” said ComEd spokeswoman Arlana Johnson.

The outage was isolated to the airport, but the cause remained under investigation as of 10:30 p.m., a ComEd spokeswoman said.

TSA officials said the outage had a “minimal impact” on security screening.

The airport has standby power to support vital electrical systems such as elevators and life saving equipment, said Karen Pride of the Chicago Department of Aviation.

Power was also knocked out at Newark Liberty International Airport in New Jersey for about 90-minutes Monday afternoon starting at 2:30 p.m.

Flights were delayed for an hour as a result of the outage and security checkpoints were effected, officials said.

ŸDaily Herald wire services contributed to this report.