Corners Tower construction delayed over fears of abandoned coal mine (CBC News Edmonton – June 28, 2015)

At least 153 mines once cut through underground Edmonton, historian says

A nearly forgotten part of Edmonton’s history has delayed a condo project in the city’s core. The lot on the corner of 95th Street and Jasper Avenue is scheduled to be the site of Corners Tower, a 28-storey development by Edmonton-based BCM Homes.

Right now, it’s little more than a hole in the ground. The project has been delayed due to fears that there might be one — perhaps two — abandoned coal mines under the site.

Construction is on hold while geological testing is done to check for mines. BCM did not respond to calls for comment. One local historian said old mines are something every developer working near the river valley should be aware of.

“This has been a chronic problem for a better part of a century,” said author Ken Tingley, the city’s former historian laureate.

Coal mining used to be a major industry in Edmonton. Between 1880 and 1970, Tingley said, at least 153 mines were dug, creating countless tunnels that spider-web under the city.

The majority were small and did little more than provide enough coal to heat a few homes. Larger mines, like the Twin Cities Mine and the Dawson Mine, exported coal to Calgary and Saskatchewan. Farmers from around Edmonton would be drawn to the mines to work during the winter.

“The Dawson mine, at the east end of the Dawson Bridge, undercuts all of Forest Heights and all that area,” he said. “There was a huge mine there.”

A troublesome legacy

When natural gas came to the city in the 1920s, many coal mines were closed, though that usually meant little more than boarding up the entrance.

“They sealed them up so that kids wouldn’t go in there … but that’s about all they did,” he said.

Many still remain, tucked away in the river valley.

The mine network quickly became a problem. Tingley said they caused some buildings and streets overtop to sink, which would break the newly installed gas lines. Explosions and fires were common.

Tingley said he was surprised the developer of Corners Tower didn’t know sooner there might be an abandoned mine under the site. He said the city should work on compiling a master list of all known coal mines to make it easier to plan construction projects.

“Anyone building, even that close to the river valley, needs to (be aware.)”

A report on what exactly lies underneath the Corner Tower site is expected sometime in July.

For the original version of this article and a radio interview, click here: