Deteriorating concrete underneath the Gardiner Expressway presents a “significant hazard to public safety,” a new report commissioned for the city suggests.

The interim report, released to CP24 by the City of Toronto,  was prepared by engineering firm IBI Group and is based on an examination of 10 random sections of the highway.

As part of the examination, delaminated concrete was detected by crews striking the surface using a hammer and noting the sound being emitted.

The method revealed that delaminated concrete on the highway is much more prevalent than the city’s visual assessment revealed earlier this year.

“The limited delamination survey reveals the importance of conducting a more comprehensive delamination survey of the entire stretch of the subject highway in order to prioritize areas that are in immediate need of repair,” the report states. “Many areas of the expressway and the associated ramps are elevated above areas accessible. As such, potential concrete spalls present a significant hazard to public safety.”

The 94-page report, which was released to the media Friday morning, went on to suggest that the city “secure” areas underneath the expressway that pedestrians do not require access to and use physical barriers as a safety net on other areas of the highway under which pedestrians do travel.

“There is no procedure or methodology that can definitively identify an imminent spalling threat,” the report states. “In order to provide protection and reduced risk, a physical barrier is required to contain spalled concrete.”

Speaking with CP24 on Friday, Public Works and Infrastructure Committee Chair Denzil Minnan-Wong said the report has uncovered some legitimate concerns.

“We commissoned the study to have an outside set of eyes look at what we are doing and I am glad that we did because they are recommending that we do some more in depth analysis and have suggested that are methodology could be improved,” he said. “We have some questions before they issue their final report, we are going to get those answered and then we are going to look at the recommendations and take them very seriously.”

Study commissioned in August

The city commissioned IBI Group to examine the Gardiner Expressway in August after six incidents of falling concrete were reported over the summer months.

“The findings are generally in keeping with what we would have accepted,” John Kelly, acting director of design and construction for the City of Toronto told CP24 Friday morning. “The Gardiner is 60-years-old, it needs some loving care and you are going to need to do maintenance.”

The city typically spends $8 to $12 million a year on maintaining the Gardiner Expressway and in May announced a 10-year initiative that will see $150 million poured into maintenance of the aging highway.

Speaking with CP24 Friday, Kelly said that price tag could rise.

“We are anticipating that we are going to need to increase spending over the next 10 years and it may be as high as $35 million a year,” he said.

The final report from IBI group is expected to be released before the end of the year.

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