Ontario won't release cause of Nipigon River Bridge failure until the fall

Ontarians won't know what caused a critical bridge in northern Ontario to fail until the fall.

The steel decking on the newly constructed Nipigon River Bridge lifted about 60 centimetres on Jan. 10, forcing a 24-hour closure that severed the Trans-Canada Highway link between the east and west.

Two independent facilities did testing on the bolts and have now submitted their reports to the Ministry of Transportation, but the government isn't making those public yet.

"The study into the bolts is only one piece of the larger picture," ministry spokesman Bob Nichols said in a statement. "The bolt study provided us with only a partial answer about the bridge, and as such we think it's premature to discuss it on its own at this time."

Government bridge engineers are conducting their own analysis and so is an independent engineering consultant with expertise in cable-stayed bridges. Those findings will then be compared and only then will the findings including the already-complete bolt analyses be made public, Nichols said. That's expected to be in the fall.

"This type of work takes time, and it has been made clear to those involved that they should take the time they need to get it right," he said.

The temporary repair done on the bridge in January is functioning as expected, Nichols said.

The $106-million Nipigon River Bridge project, the first cable-stayed bridge built in Ontario, opened the first two lanes about two months before the failure. Transportation Minister Steven Del Duca has said it's capable of withstanding winds in excess of 100 km/h and temperatures below 40 C.

Work on the four-lane bridge project continues, with construction of the third tower "well underway," Nichols said. The government has said the bridge's problems were not related to tower design.

Daily, about 1,300 trucks cross the bridge, carrying about $100 million worth of goods.