Work begins to fill sinkhole at Avonhurst Drive and Elphinstone Street

Capital Pointe isn’t the only hole the City of Regina has to fill.

A large sinkhole some 25 feet deep opened up Monday at the intersection of Avonhurst Drive and Elphinstone Street. On Tuesday, Pat Wilson — the city’s director of water, waste and environmental services — said a broken sewer trunk line was responsible for the hole’s formation.

(Regina Police Service/Twitter)

“We won’t know until we get down there, but what has likely happened (is) it’s a concrete line,” Wilson said during a media conference at the Al Ritchie Memorial Centre. “It’s likely the break was in the top and happened some time ago and there has just been an erosion of the clay soil.

“Our clay soils actually are part of what makes this a very, very rare occurrence. We don’t typically see sinkholes or large sinkholes in Regina. Typically, water makes its way to the surface and then we know there’s a problem and we can go looking for it. In this case, it appears likely that the pipe cracked and started to erode the soil.

“Because it’s such a large line, the soil was going out through the pipe and therefore nothing came to the surface. That would have happened over a period of time.”

On Monday, Regina police were dispatched to the intersection shortly before 3 p.m., when a truck was hung up on the edges of the sinkhole. The truck was towed to safety without any incident.

Mayor Michael Fougere talked about the hole during a visit to The Greg Morgan Morning Show on Tuesday.

“It’s 25 feet deep and about 20 feet wide. We have to do a bypass because it’s all filled with mud, of course,” Fougere said. “The problem we have is the shifting ground. The clay soil is going to cause us problems.”

Wilson said the city shut off water service to the area after the sinkhole opened up, but that service quickly was restored. Sewer service also resumed thanks to bypass pumping.

A giant sinkhole opened up at the intersection of Elphinstone Street and Avonhurst Drive on July 1, 2019. (Const. Mike Seel/Twitter)

Wilson suggested the repairs could take up to three days to complete. In the interim, police are asking drivers to stay away from the following intersections while crews repair the sinkhole: Sherwood Drive and Argyle Street, Elphinstone Street and Patricia Avenue, and Sherwood Drive and Garnet Street.

The pipe in question was installed in 1957 and was expected to have a lifespan of 75 years. Shifting soils can have an impact on concrete pipes, Wilson said.

The city is in the process of relining other pipes — including those on 15th Avenue — to prevent similar issues from occurring in other areas.

Wilson noted that engineers believe the current sinkhole is among the biggest they’ve seen in Regina. It also may not be the last sinkhole to appear in the city, which is where the public can play a role.

“If anybody sees a place that is sagging or bulging — because it could bulge if there’s water building up pressure underneath — or anyplace that seems unusually soft to please let us know,” Wilson said.

“We do have over 1,100 kilometres of pipe and while we do our best to stay on top of it all, we do also rely on the public to let us know when they see things that don’t look right.”