Inspectors don't know what caused this 4-year-old Calgary bridge to crack

The closure of a relatively new, downtown Calgary pedestrian bridge has been extended after a 10- to 15-centimetre crack was found.

The 10- to 15-centimetre crack will require $20,000 to $30,000 fix

George C. King Bridge in southeast Calgary is closed as workers install a temporary fix after a crack was found. (CBC)

Inspectors are hoping to determine what caused a 10- to 15-centimetre crack in a relatively new downtown Calgary pedestrian bridge.

George C. King Bridge — the bridge named after Calgary's second mayor that connects East Village and Bridgeland across the Bow River — was closed on Aug. 16.

Now, Calgary Municipal Land Corporation (CMLC) inspectors say the bridge will remain closed until Sept. 5 for a temporary repair after the crack was found on a cross-strut near the bridge's southwest corner. 

The four-year-old, $25-million bridge was due for a routine inspection in October, the agency said, but the inspection timeline was moved up after someone spotted the crack and called 311. 

Its last inspection, two years ago, found no problems.

CMLC president Michael Brown said he was shocked to hear there was a crack on the 4-year-old George C. King Bridge. (CBC)

"I'm pretty shocked, I've never seen anything like this," said Michael Brown, president and CEO of CMLC.

"We don't expect with a piece of infrastructure that's four years old, we expect if there's a problem it's going to be earlier on or it's going to be later, we don't expect to see it now. So we need to get to the bottom of this."

Susan Veres, the senior vice-president of strategy and business development for CMLC, says the steel portion of the bridge is no longer covered under warranty.

"So we have to investigate what recourse is available to us, CMLC, that we can explore to cover off some of these costs," she said. 

Workers with CMLC, engineering firm WSP and Graham Construction are going to brace the area surrounding the crack with rods and cables, to hold it together. The temporary fix is estimated to cost between $20,000 and $30,000, and should keep the bridge safe for the public. 

After that, they'll have to decide on a long-term solution and figure out what caused the crack.

Brown said engineers always anticipate some movement from vibrations and changes in temperature on infrastructure, but this was unexpected.

"The bridge is not going to fall down, but it's not performing like we'd like it to perform," he said. "So we need to get that addressed.

For now, commuters can detour either along Reconciliation Bridge or the 12th Street S.E. bridge to the zoo, Brown said.

With files from Colleen Underwood