Sinkhole causes emergency road closure

SOUTH DUNDAS – The heaviest piece of machinery on the County Road 4 (Lakeshore Drive) paving project broke through the roadway last week prompting an emergency closure.

The cold-in-place asphalt recycling machine suddenly broke through a gap (pictured left) in the roadway beside the road cross culvert located towards the west end of the roadway, bringing the project to a halt and closing the road September 13-15 while emergency repairs were made.

There were no injuries or equipment damage related to the incident.

Ben de Haan, director of transportation and planning for SDG explained that the void was caused by the washing away of the sand backfill surrounding the pipe.

“The pipe is, and always was, safe and completely traversable,” he said. “The void probably existed for years, but unfortunately, was only exposed when the heavy cold-in-place machine ran over it last Wednesday night.”

“Unfortunately, short of x-raying our roads, there was no way to know that it existed,” said de Haan.

During the road closure SDG staff removed the sand backfill and replaced it with granular B, which is the material now standardly used for backfill. “Fortunately, this work allowed us to get a good sense of the condition of the pipe, and we’ve confirmed that it will need to be replaced in the near future,” said de Haan.