It's described as a rare occurrence for a transmission tower to collapse during assembly, but CBC News has learned there have been five separate collapses in Manitoba since February.
The incidents happened between Feb. 8 and May 3 of this year, and were all the result of human error, according to Manitoba Hydro. Hydro is reviewing construction procedures as a result, and hundreds of other towers are being inspected to make sure they are safe.
"These incidents are extremely rare. We are taking extra precautions to ensure safety of all workers. Each failure occurred in an isolated area, and no one was injured," Manitoba Hydro spokesperson Bruce Owen told CBC News.
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"This stuff should not be happening. We should not be having this conversation," Owen said. "We're going to fix it."
The employees involved in the incidents work for companies contracted by Manitoba Hydro to put up the new towers.
The International Brotherhood of Electrical Workers (IBEW) Local 2034, which represents some of the workers, wants Manitoba Hydro to dig deep for answers.
"They need to do a full investigation into these lines for the safety of the public and the safety of employees," said IBEW business manager Mike Velie. "We've already had five towers collapse. This isn't safe, and it certainly isn't reliable."
"If Manitoba Hydro needs to redo a lot of these towers, that's what it is going to take," Velie said. "It's best to do it now before it comes into service or they continue building additional towers."
Velie said one of the IBEW workers at the site of the Feb. 8 incident near Gillam was so traumatized by the collapse he left the profession.
"He's left the province now. It is like being at the site of a major catastrophe. 'I could have just been killed here,'" Velie said. "These are 100-foot plus towers that are being erected. There's thousands of pounds of steel coming down and you were just underneath that."
"And if you are in that area you don't know which way that tower is going to collapse. It's going to buckle. It's going to fold. There's various ways. You don't want to be in that zone when it is coming down," Velie said.
Four of the five towers that failed are either part of or connected to the new Bipole III transmission line being built on the west side of the province, while the fifth incident happened on a new line being built east of Lake Winnipeg.
In two of the incidents, there were no workers on site when the towers failed, and the fallen towers were discovered later, Owen said.
Manitoba Hydro is setting up meetings before the end of June to review the incidents with each of the three contractors involved.
"These contractors have done this work across the country, sometimes even internationally. We've hired them to get the job done. We're concerned that these events have happened," said Owen. "It's extremely, extremely dangerous to begin with, and you're working with electricity, high voltage electricity. Safety is our number one priority here. The last thing we want to do is any employee to be hurt while doing their job."
The May 3 incident prompted an inspection of 626 towers that have already been erected to make sure the guy wires are properly connected. To date, more than 120 of those inspections have been done by the contractors, Owen said.
"The contractors themselves, at their own initiative ... are taking X-rays by helicopter of each tower that has a similar compression sleeve, or guy-wire assembly, to make sure that it's installed correctly," he said.
Tower collapse chronology
Feb. 8: A tower in the Fox Lake-Gillam area collapsed during its installation due to an error in the order of assembly of components and a lack of diagonal bracing, Manitoba Hydro said. Workers witnessed the collapse just moments after they had vacated the spot where the tower landed.
March 15: A Bipole III tower in the Dauphin-Winnipegosis area came off the pin at the foundation and went through the top of a crane, breaking the top glass panel. The crane operator had no visible injuries, Hydro said.
March 26: Workers discovered that a new tower in the Lake Winnipeg East project had collapsed during the previous few days. Hydro said two of four guy-wires had slipped out of their connectors. "As a result, an inspection of other towers found six other suspect guy sleeves on the Lake Winnipeg East Project," Owen said, adding they've since been redone correctly.
May 2: A Bipole III tower in the Interlake region collapsed while workers were assembling it, due to parts not being installed in the right sequence, Hydro said — a problem similar to the Feb. 8 incident.
May 3: A Bipole III tower in the Dauphin-Winnipegosis region fell over due to a failed connection for a guy-wire, similar to the March 26 tower failure.
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