Skip to content
Join our Newsletter

Excalibur accident report leads to industry-wide changes

Most recommendations of B.C. Safety Authority already in place

Eighteen months after an Excalibur Gondola tower sheared off do to ice jacking the B.C. Safety Authority submitted its final report of the accident this week.

Whistler Blackcomb and other ski areas have already acted on most of the safety authority's recommendations.

"We (followed up on lift manufacturer) Doppelmayr's service bulletin that said we need to drill holes in towers, and did that last summer after the snow had melted," said Doug Forseth, senior vice-president of operations for Whistler Blackcomb.

"Now we do an annual check in the fall to make sure that the hole is not plugged up so any water in the tower can be drained. That's a part of our process now."

On Dec. 16, 2008, a tower supporting the Excalibur Gondola snapped and left 43 passengers trapped for over two hours in frigid temperatures until they could be evacuated by Whistler Fire Services ladder trucks, ropes and harnesses. Twelve people were injured, one with a broken vertebrae, when the cabins suddenly dropped more than 10 metres and bounced off roofs and parking lots.

The incident took place at roughly 2:15 p.m., before the afternoon rush to download to the village.

The cause of the incident was spotted almost immediately, once investigators saw the ice that had built up inside Tower 4. The ice had expanded as the temperatures dropped, first bending and then snapping the tower below the flange where two sections were welded and bolted together.

The process is known as ice jacking, and had been seen in the industry before. There was a warning to test for water after a lift tower burst at Silver Mountain Resort n Montana on Dec. 31, 2006. However, in the case of Excalibur's tower 4, where the tower tube was partially filled with concrete to provide dampening, it was difficult to check for water.

At the time the towers were supposed to be sealed and engineers were reluctant to drill drain holes into towers because that would provide a way for water to get in. As well, the tower itself was tested in the autumn using resonance equipment and passed an inspection with the B.C. Safety Authority, which among other things certifies and regulates all ski lifts in the province.

The B.C. Safety Authority attended the accident site with three investigators, including two millwrights experienced in lift construction.

With representatives from the lift manufacturer already in town for the opening of the Peak 2 Peak Gondola on Dec. 12, Whistler Blackcomb also did a full assessment of all of its lifts to ensure that they were free of ice. The Excalibur reopened on Christmas Eve, eight days after the tower collapse.

The B.C. Safety Authority made several recommendations that will apply industry-wide in the province, but have also been adopted nationwide and by the ski industry itself to be applied around the world.

The B.C. Safety Authority's report is 34 pages long, with almost 40 additional pages of documentation in the appendix. In brief, their recommendations are:

1. All ski hill towers in B.C. must be fitted with drain holes or other means to prevent the accumulation of water.

2. Manufacturers must make sure that required inspection procedures are clearly communicated.

3. Contractors must make sure that manufacturers' safety bulletins are followed by staff and that inspection and test results are properly documented.

4. Manufacturers must ensure that "as built conditions" are documented and transferred to the owner and operator during installation (which in the case of the Excalibur would have included details about the height of the concrete fill in Tower 4).

5. The BCSA will submit its findings to the national CAN/CSA Z98 Technical Committee for review and possible code changes.

6. The BCSA will improve processes to make sure its safety officers are aware of and document manufacturers' safety bulletins.

Forseth said Whistler Blackcomb has already put most of those recommendations into place.

Additional steps have also been taken to seal the towers against water intrusion at the top after two areas were recognized where water may have seeped into the tower. Tower 5 was a similar design to Tower 4 and also had water inside.

The other recommendation that will result in changes at Whistler Blackcomb is providing all safety bulletins from the BCSA and Doppelmayr directly to the mountain's millwrights and lift maintenance department.

"Although that wouldn't have made a difference in this particular case," said Forseth. "We did a sound check or resonance test in March 2007, with an experienced millwright that had been doing the tests for 10 years."

However, under the new guidelines each millwright will get a copy and has to sign a paper stating that they received it.

Forseth says the incident was regrettable and that the resort was fortunate that the consequences were not more serious in terms of injuries. The upside, he says, is that the industry as a whole will be safer as a result of the accident and investigation.

"When Doppelmayr changed its process to allow drain holes in the towers that had worldwide implications - it's not just B.C. and Canada, it's the U.S., it's Austria and all of Europe, and everyone that has a standard."

The incident will also make things safer for lift mechanics. Prior to the accident a lift maintenance worker scaled Tower 4 twice to realign the sheaves after reports of noise. He found that the lift cable was rubbing against the protective sheaves on both the uphill and downhill side on his first visit to the tower, then returned with his tool to make the proper adjustments. He passed by the flange four times where the tower snapped, but did not notice anything unusual.

While the tower was likely leaning slightly at the time, the BCSA investigation found that there was no way that the lift maintenance worker would have noticed, as the cracks formed on the inside of the tower.

Realigning the sheaves was the proper response in this case, said Forseth, but now workers will be aware to check the tower itself as well as the top assembly.

"When I think back it scares me to death to think (the life maintenance worker) could have been on the tower when it broke," said Forseth.

The complete report is posted online at www.safetyauthority.ca.