The collapsed concert stage at the Big Countree Jamboree in the wake of Saturday's windstorm. (Submitted by Lori Gray)

The Alberta government has ordered the promoter in charge of the Big Valley Jamboree in Camrose to investigate why its main stage collapsed during a storm Saturday evening.

"Panhandle Productions is going to be putting together a proposal to do a hazard assessment," said Fiona Wiseman, a spokesperson for Alberta Occupational Health and Safety. "They're hiring expertise such as structural engineers to determine how they are going to take apart the stage.

"That will be all reviewed by Occupational Health and Safety. Once the hazard assessment is in, they'll be ordered to do a full investigation, which will again be reviewed by Occupational Health and Safety. "

Donna Moore, seen in this undated handout photo, was killed when a stage collapsed Saturday at the Big Valley Jamboree in Camrose, Alta. (The Canadian Press)

The company is co-operating in the investigation, which will be supervised by the province, she said.

Donna Moore, 35, from Lloydminster, Alta., was killed when a speaker fell on top of her when the storm blew in just before 6 p.m. Saturday at the annual country music festival. Another 75 people were injured.

On Monday, crews were at the concert site sifting through the rubble. It's expected the stage will be kept in place while structural engineers examine the remains in an investigation that's expected take as long as six months to complete.

"There's no way right now to tell what happened with the stage because people were being rescued from under it so evidence was disturbed, and these things can take a long time anyway to determine what happened so it doesn't happen again," Wiseman said.

Moore, a marketing assistant for the Lloydminster Chamber of Commerce, attended the festival with her friend, Tracy Timmerman. The two women had VIP tickets that allowed them to sit on the stage. The wind started up just as singer Billy Currington finished his set.

"All of a sudden, you just saw this big dust cloud, and Donna was still sitting down or standing at the bleachers, and I remember yelling, 'Donna, Donna, c'mon. Something's come.' And then, boom, the stage fell like a deck of cards," Timmerman said.

Part of the bleachers fell across Timmerman's back. A woman next to her was pinned to the ground by a piece of debris lying across her ankle.

Timmerman sustained minor injuries but says she feels guilty that she was able to get off the bleachers before the stage collapsed and her friend wasn't.

"What kind of friend was I to get off the bleachers and not realize that my friend didn't get off behind me?" Timmerman said. "I should have …stayed on the bleachers until she was ready to go."

The tragedy in Camrose has raised questions about the safety of other outdoor summer music festivals.

Stage designed to withstand wind: Edmonton Folk Fest

But organizers of the Edmonton Folk Music Festival — set to start Wednesday night — said Monday their main stage was designed and inspected by a structural engineer and can withstand winds of more than 100 km/h.

"We wouldn't do the show if we weren't confident," festival producer Terry Wickham said Monday.

The main stage is secured by cables fastened eight metres in the ground, said Don Snider, the production manager for the folk festival. The tenting around the main stage and the smaller side stages is designed to withstand wind, he said.

"Two weeks ago, when we had that big Saturday windstorm, we had four of these smaller versions up, and I was standing here watching them just flap gently in the wind, even though we were dropping trees all around us in the neighbourhood," he said.

The festival also watches the Doppler radar closely and will open tent walls if the weather warrants it, he added. Crews can check the rope cables on the side tents and wire cables on the main stage, he said.

The festival also has an evacuation plan that's been in place for 15 years, Wickham said.

"I don't think you can get 20,000 people out of a venue in two minutes, but I think you can get away from any structures that may be in danger," he said. "I think you could get people away fairly quickly. Obviously, they didn't have enough time in Camrose."