Government Explains Reasons for Nipigon River Bridge Failure
Article from the Ontario Construction Report – On September 25, 2016
The Minister of Transportation and the Minister of Northern Development have outlined what happened to the Nipigon River Bridge when a failure of bolts on the bridge caused a closure of the new structure in early 2016. The Liberals in a statement say there were three reasons for the failure.
However, a report in NetNewsLedger says the Progressive Conservatives and New Democrats suggest it is the incompetence of the Liberals that led to the failure in addition to the engineering and structural issues.
Transportation minister Steven Del Duca and Michael Gravelle, Minister of Northern Development and Mines and MPP for Thunder Bay-Superior North issued the following statement:
“Earlier today, we visited the Nipigon River Bridge to provide an update on the investigation into what happened earlier this year, and see first-hand how work is progressing.
On January 10, 2016, the Nipigon River Bridge was unexpectedly closed to traffic due to an issue with the tie-down connection on the northwest corner of the bridge. Following the closure, two firms were contracted to test the bolts from the bridge. The testing confirmed that the bolts broke due to overloading and not due to any flaw in the bolts themselves.
A thorough engineering analysis was then conducted by ministry bridge engineers and an independent engineering consultant to determine the cause of the malfunction. These analyses were conducted independently and reached the same conclusion.
The engineering reviews found that three main factors led to the malfunction: first was the design of the shoe plate and its flexibility; second was a lack of rotation in the bearing that was constructed; and third was improperly tightened bolts attaching the girder to the shoe plate. When combined, these three factors produced the malfunction. Neither cold temperatures nor wind contributed to the closure.
A new permanent retrofit design has been developed to address the issues identified by the engineering reviews. This permanent retrofit will ensure that the Nipigon River Bridge functions safely for road users throughout its intended useful life. This design will be reviewed by Associated Engineering (Ont.) and ministry bridge engineers and will also be applied to the south portion of the bridge, where construction is progressing well. Preliminary estimates for the initial repair work in February and the final repair to be implemented are between $8 and $12 million.
This fall, the province will also move forward with a formal route planning study and Environmental Assessment for an emergency detour route. This is expected to take approximately 18 months to complete. While our government has full confidence that the retrofit, once complete, will ensure that the bridge is safe for all users, this detour route would provide an alternate option for local residents and businesses in an emergency.
The safety of the travelling public is of paramount importance to our government, and we appreciate the ongoing patience and understanding of the people who use and depend on this bridge.”
However Ontario PC transportation critic Michael Harris said:“After three months of sitting on test results and analysis regarding the cause of the Nipigon Bridge failure, we now know why the Wynne Liberals were eager to keep them secret.
“From lack of oversight and inspection concerns to clear design flaws, the list of mistakes leading to the failure of the Nipigon Bridge only a few short days after opening points directly at the Wynne Liberal government. “Today’s report leads to further questions about this government’s mismanagement of a vital bridge closure”.
“Even before the bolt testing, the immediate visual inspection revealed that some of the broken bolts were rusted at the break – meaning they were shorn off days, maybe even longer, before the rest of the bridge deck lifted on January 10th. This was clearly a disaster waiting to happen.”
“When was the last inspection before cars were sent over an already breaking bridge,” Harris said. “And why didn’t someone pick up on the fact that the bolts weren’t properly tightened, not to mention the series of design flaws?. In the end we’re paying another $8-to-$12 million to fix a $106 million bridge failure that put the lives of Ontarians at risk due to the Wynne Liberals’ lack of oversight.”
The New Democrats, in a statement say: “The upshot of these independent engineering studies is that the Nipigon Bridge failed because the Liberal government didn’t take their project oversight responsibilities seriously. Any engineering and design installation failures should have been caught before the Ministry of Transportation opened the Nipigon Bridge to passenger traffic in the first place.”
“The buck stops with the Minister of Transportation. Unfortunately, by keeping Ontarians in the dark for more than 8 months, he has seriously eroded public confidence in the safety of Ontario’s road and bridge network. Without any further delay, Minister Del Duca must tell Ontarians exactly how much his government’s failures will cost Ontarians, whether the repairs could end up costing us more than $12 million, and what concrete steps he will take to make sure that such a dangerous lack of government oversight never happens again.”