OTTAWA, ON – An independent review of the 174 sinkhole was released Friday afternoon.

The pipe was visually inspected through a TV – but in the opinion of the review – the inspection should have been followed up with a physical examination to look at the pipe more closely.

Steve Burns of B.M. Ross and Associates said the structure was at great risk – considering its age, size, material and location – and it was not acted on before the pipe’s structural integrity was lost.  He said the City’s record of the pipe was not correct.

“The records indicated all of the pipe was galvanized,” said Burns.  “We subsequently learned the tunnel liner plate was not and therefore much more susceptible to corrosion.”

Five recommendations were presented to the City – expanding their definition of high-risk storm sewer asset, examining all high-risk storm sewer assets, assessing the quality of their high-risk storm sewer asset inventory and addressing weaknesses, following up TV inspections with physical inspections and considering the consequences of not acting quickly with capital projects.

City staff will report on the review at the Environment Committee Meeting on January 15, 2013.