The city of Ottawa says it's not to blame for that massive sinkhole collapse on Rideau Street this summer.

The sinkhole happened on the morning of June 8th; it grew fast, eventually spanning the width of the road.

It has taken six months and two weeks to get to this point: a report from the city that still doesn't explain the cause of the sinkhole but says the city wasn't to blame.  The question then: who is?

Locksmith shop owner Michel Kiwan was hoping to unlock a mystery today. What caused the earth to open up on Rideau Street June 8th and swallow one of the company's vans?  The driver with First Choice Locksmith fortunately wasn't inside. But the vehicle and the tools were lost for good.

“I need to know the answer right?” Kiwan said inside his shop as he cut several keys for a customer, “I need a proper answer. The city should know if it's not their fault, whose mistake?  The mistake happened right, so who you gonna blame?”

The city says it now knows the answer to part of that question: that it is no to blame.  According to city solicitor Rick O'Connor:

“The city's external technical experts…are confident, based on their analysis of all the available evidence, that the sinkhole was not precipitated by a failure of city infrastructure."

What's still unclear though is where the blame lies.  And finding the answer was made more difficult, by the initial response. Right after the hole opened up, contractors poured 3-thousand cubic metres of concrete to secure the sides, effectively burying clues. 

But the councillor for the area says city data shows the water mains weren't the issue.

“Weare in a strong position with a third party report from an engineer,” says Mathieu Fleury, “Keep in mind the city has a lot of data with respect to water pressure in our pipes We have an understanding about the exact moments and the sequence of the incident and we believe the water mains were in good condition and that the soil underneath, relating to the excavation perhaps would have been the cause of Rideau Transit Group (RTG)’s work in the area.”

“The city says there have been 31 insurance claims for compensation from businesses that were affected by the sinkhole.  The city has also put in a claim for about $1.5 million for what it says it spent working on the hole. 

That would cover the costs for emergency responders and maintenance crews.  Fleury believes Rideau Transit Group has made a claim for about $8.5 million.  RTG wasn't talking today.  Neither was Ottawa's mayor but in a year-end interview  recorded earlier this week, Jim Watson said with so much money at stake, they need to let the process unfold.

“If it's our fault, our insurance company has to pay,” Watson said, “If it’s RTG’s fault, they're on the hook. So we want to get it right and have the evidence there, so that whoever is responsible pays up.”

This report isn't being made public because of all the legal claims over the sinkhole.  The project as the sign on Rideau suggests, remains on track for revenue service in 2018.