Construction of the Bearspaw South feeder main project continues to hum along, with the latest milestone being the completion of microtunneling on the first stage.

The City of Calgary said Wednesday that the project continues on schedule, with the microtunneling and the concrete carrier pipe now installed.

Stage A of the project, which began back in January, involved microtunneling on a path adjacent to that of the current Bearspaw South feeder main line, and then installing a concrete carrier pipe that will eventually have a new steel feeder main installed inside it.

“The completion of Stage A microtunneling is a significant step forward for the project,” said Darren Finney, manager, major projects with the City of Calgary.

“This complex work involved tunneling beneath major infrastructure, (and) minimizing impacts on the community. With the concrete carrier pipe now in place, we will continue installing the new steel feeder main, preparing for the critical system connection work planned for the fall.” 

The first stage covered nearly 3.7 kilometres between the Shaganappi pump station and 73 street NW. While the tunneling and the concrete carrier pipe have been complete, just over half the steel pipe remains to be installed.

Mayor Jeromy Farkas said Wednesday that the progress shows city staff haven’t skipped a beat over the summer.

“This is a project unlike any other. What we’ve been able to deliver here in Calgary, this milestone, is something that a lot of other cities, a lot of other provinces, and countries simply couldn’t,” he said.

“So, this is all about the power of community, us coming together.”

Work continues on Stage B cut and cover

Construction on Stage B, which is open-cut construction along 34 Avenue in Bowness, began in June, and the city said progress remains on schedule.

That process requires opening the ground, laying the pipe in a trench and then eventually covering it back up.

More than one kilometre of the Stage B feeder main steel pipe portion has been installed, the city said. Construction is currently active on three blocks, with four blocks now reopened to traffic. Two more blocks will be opened next week, the city said.

Continued work to connect the new feeder main into the water system will begin in September. Along with unrelated work on the North Calgary Water Servicing feeder main, it will require that the Bearspaw water treatment plant be shut down temporarily.

Depending on weather and water demand, that may require temporary outdoor water restrictions, something Mayor Farkas had alluded to in a social media post last week.

“We still have a bit of work … to do,” he said.

“We want to be transparent with Calgarians about the requirement for some water restrictions in the coming weeks in order to complete the final tie-in.”

In October, the actual connection of the Bearspaw feeder main to the water system will be done, requiring the existing Bearspaw feeder main to be shut down. Stage 4 outdoor water restrictions and indoor water conservation will be needed at that time.

The City of Calgary estimates that the feeder main commissioning will begin in mid-November.

“This will include disinfecting the pipe, filling it with water and taking the existing feeder main out of service,” the city said.

“No restrictions are anticipated during this time.”