City ignored advice to urgently replace Dufferin Bridge years before emergency closure, documents show
ABOVE: Safety concerns with Dufferin bridge identified years before closure. Jackson Proskow reports.
The city announced it was closing the Dufferin Street Bridge to vehicle traffic on a Friday afternoon in June. The Mayor toured it the following week, saying it was “in terrible shape – it’s not safe.”
But the city had known that for years: City staff and outside engineers had called for the bridge’s urgent replacement going back to 2004, according to documents obtained by Global News through access-to-information legislation.
In 2008, consulting engineering firm AECOM identified serious problems with the bridge and said reinforcement work needed to be carried out immediately. The deck was in “very poor” shape; inspectors, looking up at the bridge from underneath, spotted a hole that went all the way through the concrete to the asphalt above.
“I would not walk on this,” Ryerson engineering associate professor Lamya Amleh told Global News in an interview last week, looking at a picture of the hole from the 2008 report. “It is a very, very, very severe condition. This one, it would not be safe to drive on top of this.”
“We would expect that in the worst case scenario for the existing deck, a large hole could open up in the deck,” reads the 2008 report. “However, it is extremely unlikely that a vehicle would fall through that hole, though it would be severely damaged.”
Part of that 2008 report:
Even more worrisome were connections between the main support girders and floor beams. Inspectors couldn’t actually see how corroded the steel was beneath the concrete. But based on the poor condition of the visible steel nearby, they said “it is almost a certainty” that they were in very poor condition as well.
These connections were critical to the viability of the bridge, which was designed without redundancy: If one of these severely corroded connections failed, the whole bridge would fall.
“That is very alarming,” Amleh said.
The 2008 report recommended immediately installing a support system for the bridge beams and performing monthly visual inspections on the bridge deck, as well as doing local repairs as problems were spotted. This might keep the bridge in service for two more years, consultants said.
According to Michael D’Andrea, Executive Director of Engineering and Construction Services for the City of Toronto, the city did repair the bridge deck after this report. The next year 2009, they asked the same engineering firm for ways to extend the life of the bridge.
The report suggested immediately posting load restrictions on the bridge, as well as either extensive rehabilitation work or replacing the entire bridge with a temporary structure.
The city chose to restrict vehicle weights on the bridge and immediately replacing the old structure with a temporary one intended to last until the new Dufferin Bridge was built in 2016, D’Andrea said.
But the temporary bridge was never installed.
D’Andrea isn’t sure why.
“I suspect, speculating, that they were waiting for the outcome of the environmental assessment and then a final decision in terms of how imminent would be the construction of the new bridge.”
So the bridge sat in limbo, receiving some minor deck repairs but little else between 2009 and 2012.
According to a 2013 summary prepared by Jodie Atkins, a senior engineer in the city’s Construction and Engineering Services department, for various managers in Capital Works, the city ignored 2009 recommendations from outside engineers to inspect the bridge every six months, strengthen the connections between the floor beams and girders and repair the hole in the deck.
Part of that document:
“I don’t know what the reasons for that were,” D’Andrea said.
“Where there were any deficiencies identified in the bridge deck, those repairs were made,” he added.
“We wouldn’t have left that bridge deck unattended if there was a deficiency found with that bridge, particularly if there was a hole in the deck.”
It appears even that didn’t happen: “The asphalt was repaired but not the concrete below,” Johnston said in a subsequent email. “The hole was very small and not considered to be a concern.”
In 2011, a city auditor wondered why repairs or rehabilitation hadn’t been completed. Engineering staff responded in an email that the bridge could be maintained with a load limit.
A provincially mandated inspection in November, 2012 found many of the same problems as the 2008 assessment: a hole in the deck, potential for “punching failure” (meaning a car could break through the top of the bridge), corrosion and deficiencies in the weight the bridge could carry.
The next spring, city staff reassessed.
“The bridge was deemed to be operable this past year, and in May, we just felt that from a risk profile standpoint, it was time to shut the bridge down,” D’Andrea said.
AECOM was hired to determine how long the bridge could remain open.
But well before its report was completed May 31, city staff knew the outcome.
“Based on the condition of the bridge,” said a briefing note for Capital Works managers on May 21, 2013, “and in anticipation of AECOM’s assessment, this has been deemed an emergency condition ie. a public safety issue.”
As predicted, AECOM’s report said the bridge had reached the end of its design life and recommended its immediate closure to vehicle traffic.
But “AECOM inspectors did not attend the bridge site in May 2013,” Johnston said in an email to Global News.
“In view of the planned replacement of the bridge in 2016 and following another winter freeze/thaw cycle, staff reviewed all existing information on the Dufferin Street Bridge in May 2013. Considering the expected corrosion that would have occurred over the winter and erring on the side of caution, it was determined that the bridge needed to be closed to vehicular traffic.”
“For us, public safety is paramount,” D’Andrea said, adding that public safety was not at risk until May. “A bridge should remain open as long as it’s been deemed safe for travel. And that is the case with the Dufferin Bridge.”
Perks and Minnan-Wong said they heard of the bridge’s imminent closure shortly after the city received AECOM’s May 31 report.
Perks said he was made aware at a briefing some time between 2008 and 2010 that parts of the bridge were rusting and “creating a risk of holes,” and he knew the structure needed to be replaced, but didn’t know the extent of the problems before May.
“My understanding had been that the bridge was going to be maintained in a safe state until the replacement project,” he said.
“I think that the system worked,” Perks added. “We did not have a catastrophic failure. Nobody was hurt. And when professional city staff felt that the bridge was unsafe, they came forward, they told us and the bridge was closed. Thank goodness that we didn’t have the kind of catastrophic failure that Montreal experienced a few years ago, and I want to congratulate the Toronto public service on that.”
Minnan-Wong, who has been Public Works chair since late 2010, says he was also taken by surprise. But had he known sooner, he says, things would have been different.
“I wasn’t aware. I don’t think council was made aware. I think if we knew of the significance of the damage, it probably would have been closed a whole lot sooner, or at least the repairs would have been done. But council wasn’t aware of that.”
If he had seen the 2008 report at the time, he says, “There would be, like, no questions asked: This thing’s closing.
“This is the big question: why did they not do something about it? This is an easy one, right?”
© 2013 Shaw Media