Overnight, a large excavator cut through a section of a former rail bed to release water trapped behind a 30-metre high embankment near Birdtail Creek and PTH 45.
At this time, water levels are being monitored. The effectiveness of the breach may be affected by the recent rainfall and resulting inflows to the site.
The water is making its way into the Birdtail Creek at a flow of 100 to 150 cubic feet per second. Birdtail Creek won’t exceed its previous crest as a result of this cut.
The situation is being closely monitored.
The cut was made about 200 metres west of the failing embankment. Before the cut was made, heavy rock and membrane were put into place to reduce excessive erosion and contain flows.
The controlled breach and pumping, combined with the slow flows from the culvert, are expected to reduce the risk of embankment failure and a surge of water flowing downstream. However, risk of embankment failure is still high as only the top five feet of water will be removed from behind the embankment.
The situation is being monitored closely and will be updated as conditions change.
Under usual conditions, spring run-off would flow through a large box culvert at the base of the embankment.
The frozen box culvert at the base of the embankment has been holding back a significant amount of water near PTH 45. Portions of the embankment have started to slide over the last three days, prompting concerns about flash flooding along Birdtail Creek.
As a result, communities downstream of the embankment have evacuated residents in low-lying areas and taken steps to protect homes and critical infrastructure.
