Damage from the March 14 twister could affect the Georgia World Congress Center far beyond the need to fix gaping holes in the roof, replace broken exterior windows and rearrange furnishings that were tossed around like packing peanuts.

It may dash the convention facility's hopes of breaking even financially this year.

Jessica McGowan/AJC (ENLARGE)

The March 14 tornado that damaged the Georgia World Congress Center has sent some groups elsewhere in Atlanta.

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The price tag for the damage is not yet known. State Insurance Commissioner John Oxendine predicts at least $100 million; GWCC officials say the costs are still being assessed.

But even before the tornado struck, GWCC officials were concerned about a slowing economy.

The effects of fewer meetings at the convention center are likely to spread to other metro Atlanta businesses.

Downtown hotels, restaurants, cabdrivers and others depend heavily on convention traffic, hospitality leaders say. Millions pour into city coffers every month from Atlanta's $11.3 billion tourism industry, which includes conventions. The average attendee at a GWCC convention, trade show or meeting spends about $1,194 for every overnight stay in Atlanta, according to a 2007 study by the University of Georgia's Selig Center for Economic Growth.

It's too early to determine which events booked at the GWCC will have to be canceled, including next month's Atlanta Journal-Constitution International Auto Show and FIRST Championship, a student science and technology competition, said Katy Pando, a spokeswoman for the GWCC. There are more than 30 events on the GWCC's calendar in April alone, including meetings at the Georgia Dome and Centennial Olympic Park.

In February, GWCC Executive Director Dan Graveline told the center's board that he was beginning to see signs of softening revenue in the second half of the fiscal year.

A major real estate show that month had lower attendance than projected when it was booked three years ago, and attendees spent less on food and beverages. Utility sales have also slipped as exhibitors use less power for booths, he told the board.

"We thought February would be one of our better months," Graveline said.

That softening comes on the heels of January revenue figures that were down almost twice as much as officials had projected: a $206,299 net loss instead of the $110,323 expected for the month. The center, however, is in the black for the fiscal year, which began in July. It projected a loss of $2.5 million, but currently has a profit of $403,881.

How the storm impacts the GWCC will depend on a number of factors, including getting the building back in full operation; making it clear to customers the city is still open for business; and, if needed, recovering some losses through insurance, hospitality officials said.

"Being functionally operational and 100 percent operational are two different things," Oxendine said.

Hospitality officials have been working to minimize business losses because of storm damage. The GWCC plans to reopen Building C this week for two scheduled conventions worth about $14 million in direct spending. The groups — International Window Coverings Expo and National Propane Gas Association — will bring in about 13,000 visitors.

On the flip side, the center lost the Big South Qualifier, a volleyball tournament this past weekend with 38,000 attendees. The contest was moved to other facilities around metro Atlanta, including the Cobb Galleria Centre and the Georgia International Convention Center.

Downtown booster group Central Atlanta Progress also is moving its annual meeting this week from the GWCC to the downtown Atlanta Hilton hotel.

Gregory Pierce, executive vice president, chief financial officer and chief administrative officer of the Atlanta Convention and Visitors Bureau, said keeping the meetings in the metro area lessens the overall economic losses.

"What the Congress Center loses is in rental rate and food and beverages," he said.

The real challenge is how quickly GWCC officials can get the rest of the building open. Because of the facility's size — 1.4 million square feet of exhibit space — the GWCC can accommodate several groups simultaneously.

It was forced to pull the plug on hosting a meeting of the Clinical Laboratory Management Association, which was supposed to begin in Building B on Saturday. It might have been moved to Building C, but there was not enough room for it and the propane show. CLMA said on its Web site that the show has been canceled, but GWCC spokesman Pando said convention leaders are trying to find another date for the meeting.

"It is postponed," she said. "We are working with them and hope to get them in the building."