Due to increased capacity on the Portage Diversion, the controlled release through the Assiniboine River near the Hoop and Holler Bend will likely occur at 8 a.m. tomorrow morning. Residents in the area should be on a high level of alert for possible evacuation, as conditions are subject to change. Residents are advised to follow instructions from their local rural municipalities.
The initial release of water would be approximately 2,000 cubic feet per second (cfs) and could gradually increase to 3,000 cfs within 24 hours. This will be continually reassessed and modified as necessary. This planned release would cause overland flooding in the area but it would be a slow and controlled release of water that would slowly move through the area. Homes that would be the first to be impacted by the release have already been evacuated and are being protected with flood tubes that are being placed by 100 Canadian Forces soldiers.
The controlled release will only be undertaken tomorrow if the Portage Diversion is unable to handle even higher flows or if the Assiniboine River dikes between Portage la Prairie are at a serious risk of breaching and causing significant, uncontrolled flooding.
If a serious problem that could cause a breach on the dikes occurs at any time between now and tomorrow morning, the controlled release time may have to be moved up. If this happens, notification will be provided as soon as possible, but residents should be prepared to leave on short notice if necessary.
This controlled release is expected to affect an area of approximately 225 square kilometres and around 150 homes. An uncontrolled breach could flood a large area and as many as 850 homes and 500 sq. km. This would occur at a much higher flow rate than a controlled release.
The area around the controlled release point is closed to ensure the safety of workers and the success of the operation.
Along the Assiniboine River dikes, provincial staff and 300 Canadian Forces soldiers continue to reinforce, patrol and monitor the area.
Approximately 100 soldiers are also working to protect 39 properties in the path of the spill-over from the Portage Diversion east and west banks.
A special program is being developed to provide comprehensive compensation to homeowners affected by the controlled release and spill-over from the Portage Diversion.
The controlled release site was selected as it provides for the least risk and best management for the controlled release. It is the closest location to the La Salle watershed and provides the most predictable flow of water after the release. It is also the most reliable site for equipment and workers to manage the release. Other areas are not accessible due to current conditions.
A map showing an up-to-date area that would be affected by the controlled release is posted on the Manitoba government’s flood website at www.manitoba.ca. The map is the projected scenario for a 4,000 cfs release, and water would take several days to extend to the further reaches of the mapped area.