City crews have determined the cause of recurring sinkholes near the intersection of Carney Street/20th Avenue and Winnipeg Street/Massey Drive.
They have successfully removed enough water from around a large storm sewer pipe to be able to identify a failure in the pipe about three metres north of a manhole at the site.
The section of storm sewer pipe is approximately six metres in length and has partially collapsed below the groundwater table. Holes of up to 10 inches in diameter have formed on the pipe and, during large rainfall events, water flows suck nearby material into the pipe and cause sinkholes.
Crews must now expand the excavation site to allow them to safely access the storm water pipe and fix the issue. As a result, the southbound lanes of Winnipeg Street will be closed starting on Tuesday and until further notice as crews remove the damaged section and replace it with a concrete chamber, which will restore the integrity of the pipe and allow for easier maintenance of the storm system.
Earlier this summer, crews installed a temporary dam to allow enough water to be removed from the area around the sinkhole to allow crews to identify the cause.
The city expects the operation will take a few more weeks to complete. The City appreciates the patience of residents and encourages motorists to seek alternate routes and to drive cautiously and follow signage when around road crews.