Calgary releases early findings on cause of major water main break

The city of Calgary has released preliminary findings into the cause of the major water main break this summer.

The release from city officials suggest several factors led to the Bearspaw South feeder main rupturing in northwest Calgary on June 5.

The reason for the break laid out by the city include microcracking of a protective mortar on the outer layer of the pipe, high chloride levels in the soil, and wires snapping because of corrosion.

The city’s general manager of infrastructure services Michael Thompson says the pipe has been responding well to the repairs made since the break in June.

“Through our acoustic monitoring, we have recorded only two wire snaps on the feeder main between October and November,” says Thompson in a statement.

He says the city recorded 23 wire snaps through July and August.

The city says work on the final two segments of the feeder main are almost complete. Work continues along Parkdale Blvd NW and near Memorial Drive and Crowchild Trail NW.

The major break along the pipe forced the city into Stage 4 outdoor water restrictions that were first introduced right after the rupture in early June.

The restrictions meant Calgarians couldn’t use potable water outdoors and anyone caught doing so was faced with a fine of $3,000.

After declaring the water emergency over and most water restrictions being lifted in July, right as the Calgary Stampede kicked off, water restrictions returned in late August after it was discovered more repairs were needed. A pipe diver device discovered 21 problem spots along the pipe following the initial repairs.

The preliminary findings on the cause of the break are set to be released at a council meeting on Nov. 26, with a full report to follow on Dec. 11.