A power outage Saturday afternoon forced 500 to 600 people at a swim meet to evacuate the Cape Central Pool after the structure's bubble roof began deflating.

No one was injured in the incident, which occurred after a back-up motor failed to kick in to keep the blower that inflates the roof operating.

The power outage occurred about 3:30 p.m. when a lightning protection device exploded on a Union Electric utility pole on Thilenius Street behind Southeast Missouri Hospital, causing a circuit breaker to open.

The outage affected about 3,000 customers over a large area of the city, extending from Southern Expressway to the Independence Street area, and from near Sprigg Street to west of Kingshighway.

Power was off for about 45 minutes, Union Electric District Superintendent A.D. Cox said.

The Kiwanis Great Times Swim Meet involving 19 teams was under way at the pool when the outage occurred.

Swimmers as young as 9 years of age were there when the power went out.

Cape Swim Team coach Scott Christie said the emergency generator malfunctioned.

"It kicked on for a minute or two and then it went off, and then sporadically every couple of minutes you would hear it try to come on," he said.

"As soon as the generator stalled out, I knew the bubble was coming down," Christie said.

The life guards ordered everyone to leave. When the three emergency doors were opened, the bubble quickly began deflating.

"It was scary at first for some people," Christie said.

Pool Manager Angela Light said the incident particulary frightened some of the younger children.

The inner lining of the roof was torn slightly when the wind blew part of the collapsing bubble onto a metal support pole.

Fortunately, the bubble didn't totally deflate. An out-of-town parent at the meet got the back-up generator running again.

Power was restored about 4:15 p.m. The bubble was re-inflated and the meet resumed.