HONOLULU -- While many residents on Oahu felt the earthquake off the Big Island on Sunday, the biggest problem was a power outage. The outage affected the entire island shortly after the earthquake.

Many areas were still without power at 11 p.m. By 9:30 p.m., Hawaiian Electric Co. reported that about 147,000 customers out of 291,000 had power restored.

The generators went off line after the quake because of the way the system is set up, according to HECO spokesman Jose Dizon.

The Honolulu International Airport got its power back at about 6 p.m.

The airport was a scene of confusion for most of the day. After announcing that the airport was open in the morning, airport officials were warning people to stay away from the scene of growing confusion, frustration and even restroom filth by the afternoon.

Counter workers were unable to process tickets or baggage through computers. This left long lines of travelers sitting with nowhere to go.

Airplanes landed, but passengers were not allowed to leave the planes until crews could get jet ways working. Some passengers said that they remained on board jets on the tarmac for more than three hours waiting to get off.

Many flights into Hawaii were canceled or delayed because of the outages. KITV 4 Island Sports director Robert Kekaula was stranded in San Francisco because of the problems. Kekaula was in California to broadcast the University of Hawaii football team's game against Fresno State on Saturday.

Without electricity, Transportation Security Administration workers could not use scanning machines. That prompted workers to check passengers by hand.

Some of the restrooms toilets backed up because of low pressure that could not flush completely.

Once power was restored, it took a few hours for passengers to get on flights or be put up in hotels overnight. By 10 p.m., nearly all of the interisland travelers found accommodations.

The Board of Water Supply asked residents to conserve water during the outage and when power was first restored. It would take time for reserves to refill, BWS spokeswoman Su Shin said.