Sinkhole stalls city's new emergency ops centre

Work has halted on Calgary's new emergency operations centre because of a sinkhole adjacent to the city construction site.

Crews had been excavating at the site at 637 First St. N.E. for the $54-million centre when part of the street collapsed, and cracks appeared across the roadway.

The city has closed the road on First Street between Fifth and Sixth Avenues until engineers can determine what caused the metre-deep sinkhole and determine how to fix it.

"We'll take remedial action to make sure it's fixed and not put the public at risk," Mayor Dave Bronconnier told CBC News on Monday. "We don't want to see a vehicle or a person fall into a hole."

Don Horton, who owns a three-storey apartment building nearby, said he believes the project is threatening his property. He said he's noticed several new cracks in the foundation of his building, and that the ground around it has sunk by half an inch.

"I think they're going to have to buy us out, that's where I'm looking. I don't see how this is ever going to help the resale value of the property," said Horton.

"All of a sudden we have this … hole that the city is doing, and not doing anything for the tenants and for myself telling us about what's happening."

The city posted a notice on Horton's building on Saturday about the sinkhole, stating that "as a security precaution, project engineers are inspecting and/or monitoring surrounding areas and nearby buildings."

Sharon Purvis, director of corporate properties and buildings for the City of Calgary, said city engineers have not detected any shifting in structures around the construction site.

"We have been monitoring the adjacent apartment building both pre-excavation, during excavation and continue to monitor it [for] a number of days. Our surveying results are nothing has moved on the building," she said.

"We will be taking a look at the engineering reports — an investigation that's undergoing right now and then that will determine whether we take any changes or how we move forward with the actual facility construction."

Construction will not resume until the walls of the four-storey excavation pit are reinforced, said Purvis.

She said private contractors tested the soil before the excavation began earlier this year.

The city's new emergency operations centre is slated to open in 2012 and will replace the current facility in Rotary Park.