The electricity is on today and classes are back in session at South Junior High and Broken Arrow School.
Officials said the power outage that canceled classes Wednesday could have been much worse.
"It's pretty amazing we didn't have a major, major explosion," said Will Fernandez, South's principal.
It was freak flooding into a high-voltage panel on Tuesday night that led to canceled classes Wednesday, according to Fernandez and Bryan Hunter, the district's maintenance supervisor.
Hunter said Lynn Harrod, South assistant principal, noticed a lighting problem Tuesday night inside the school as a light rain fell outside.
Harrod sent a custodian to check the boiler room on the north side of the school. The custodian began walking down steps into the boiler room, but stopped when she saw the area was flooding.
Rainwater was cascading in from above and into the "switch gear," the main, high-voltage power distribution panel that serves both South and Broken Arrow, Hunter said.
Fernandez said he got to the school about 7:25 p.m. and found Hunter on the steps to the boiler room, shining a flashlight into the area above the switch gear.
They realized the water was flowing from the parking lot through a sinkhole underneath a sidewalk that had shifted. The water was draining through one of the underground electrical conduit pipes directly into the live 480-volt panel.
At approximately the same time, on the south side of the building, some 250 to 300 parents had arrived for a 7:30 p.m. orchestra concert.
"It was a scary situation," Fernandez said.
School officials realized the wiring in the switch gear could short out at any second, possibly causing major arcing and an explosion.
They needed to cut the power immediately. But they couldn't cut the lights before they evacuated the building.
Fernandez rushed to stop the concert, but students were already in the middle of the first piece.
After it ended, Fernandez told the crowd about the problem. He said everyone left quickly.
"Several of the parents commented 'that's why we're getting a new building,'" Fernandez said.
South, which was opened in 1968, will be razed at the end of the school year and replaced by a new $31.9 million building now under construction just northeast of South and adjacent to Broken Arrow.
Once the families left, Westar Energy cut power to the switch gear so Fernandez, Hunter and others could go into the flooded area to examine the problem.
Meanwhile, school faculty and staff were called and told classes would be canceled for the next day. The district told the news media, in hopes of getting the word out to students.
Only about 15 to 20 cars of students showed up for school Wednesday morning, Fernandez said. A few elementary students who walked to school were driven to a relative's home where there was an adult at home, he said.
Fernandez said South was lucky no arcing occurred, sparing damage to the old electrical panel.
"This stuff is so antiquated. I don't know if we'd ever found anything to replace it," he said.
Hunter said the water was removed from the room and power was restored.
He said repairs would cost "several hundred" dollars rather than the several thousand had there been an explosion.
"If it would have arced in the panel, we would have had more than one day off," Hunter said.