Cambridge council has given the go ahead to replace a crumbling, century-old retaining wall on Blair Road.
At Tuesday evening’s meeting, council endorsed a $1.5 million option to replace the city-owned 62-metre long wall at 45 Blair Rd. with a new stone facing wall which a staff report said aims to resemble how the existing wall would look when first built.
Jamie Croft, Cambridge manager of infrastructure engineering, said this option is supported by the heritage advisory committee and provides “a balanced approach with modern day engineering best practice and design.”
“The cost is in the middle range of the options presented providing a balance between cost and heritage and has a lower project risk compared to repair options and solid stone facing options,” he said.
The lifespan of a new wall built to modern standards was put at 75 years with a lifecycle cost expected of $1.6 million.
The wall is considered a heritage attribute within the Dickson Hill Heritage Conservation District and therefore demolition or work on the wall required approval from council.
Laura Waldie, Cambridge senior planner heritage, told council staff aren’t sure exactly when the wall was built but it is believed to have been built in the late 19th Century or in 1908 based on that year being etched into the wall although this could indicate a year when extensive repairs were done on it.
The current wall was found to be in poor condition following assessment. The report said the wall’s original lime-based mortar allowed for moisture to pass through and the front was covered in a material which reduced moisture wicking and “likely increased decay.”
Several areas of the wall are showing signs of movement, rotation, deflection and bulging, the report said.
The wall became a safety concern to the point where the sidewalk beside it was closed.
New wall construction is expected to take six months and may require either a full road closure or reduction to a single lane.