The water main break that caused a power outage at Buffalo Niagara International Airport occurred around the time workers were inspecting the water pipes that feed the airport's sprinkler system, officials said Friday.
Airport officials say they do not know what caused connecting 10-inch steel pipes to burst Thursday, and they said they would not rush to judgment.
But they are looking into the possibility that adjustments to the water flow through the pipes during the inspection might have played a role.
The water main that broke was installed when the $56 million terminal was built just a couple of years ago.
"It's a onetime kind of event," said Luiz F. Kahl, chairman of the Niagara Frontier Transportation Authority. "It shouldn't have happened. It happened. We'll go back and go through everything and determine the cause."
"Even at a 2-year-old airport, things are going to happen," said NFTA Executive Director Lawrence M. Meckler.
As part of the routine inspection by the airport's insurance company, airport workers Thursday adjusted the flow of water in the pipes.
"It just so happened they were inspecting our pipes when this water break occurred," said Walter D. Zmuda, the NFTA's general manager for engineering. "They weren't in the same room. And there's nothing to believe at this point that that's what caused the break. They were performing tests they routinely perform for our fire protection system."
The incident has prompted airport officials to consider improving the backup power system so airport operations are not so disrupted if the power ever goes out again.
US Airways, the airport's dominant airline, canceled more than a dozen flights in and out of Buffalo after the airport lost power at about 3:40 p.m. Thursday. Other airlines maintained their service.
Once the water main broke, water filled a 10-foot-deep pit underneath the west concourse and then flowed into a room with an electrical panel. The power shut off once the water reached the panel, and that triggered the backup system.
The backup system now provides between 25 and 30 percent of the power the facility needs to operate normally.
While the backup system allows metal detectors and X-ray machines to operate as usual, power was lost to the airlines' computers, revolving doors and escalators and sensors on sink faucets and toilets.
Also without power were telephones, jetways and baggage handling systems.
The outage did not affect the control tower and runway lights.
The backup system was designed to provide enough emergency power to evacuate the terminal -- not to maintain operations, Zmuda said.
The airport will look for a way to provide more backup power to other parts of the airport to help airlines maintain their service during outages, Zmuda said.
"What we're looking to do is try to see if we can put out emergency power to ticket counters and to one inbound baggage conveyer and one outbound baggage conveyer," Zmuda said. "That'll be our goal."
US Airways decided to cancel flights rather than try to operate without full power, said Jeffrey J. Kline, station manager at the Buffalo airport.
"It was just obvious from a safety factor," Kline said. "It would have made no sense not to."
About 1,000 US Airways passengers in Buffalo were affected by the canceled flights, and as many more who had hoped to fly to Buffalo from elsewhere either flew to Rochester or waited a day to eventually fly into Buffalo.
Despite the inconvenience, US Airways officials praised the NFTA's response.
"I thought the airport really handled the situation tremendously," Kline said. "The total coordination through the NFTA was excellent."
The airport quickly called in engineers, an electrical contractor and airport operations and maintenance officials. Firefighters from the airport and a couple of nearby community volunteer fire departments were summoned to help pump out the water.
The two main challenges for repair workers were to fix the broken water main and then repair or replace the electrical equipment. It took two hours just to pump the water out.
Once the water was drained, it took an hour for the equipment to dry. Six propane heaters were brought in from an unrelated construction job at the airport to help dry the equipment, Zmuda said.
Power was restored shortly after midnight.
Thursday's power outage triggered the airport's emergency system for the first time since the new improved airport went into service in November 1997, Meckler said.
NFTA and airport officials were quickly mobilized when the power outage was reported, he said.
"You hate to have a crisis, but it's good to see how well you react," Meckler said. "We have the confidence that when something happens, we're ready at the quick."