Flood forecasts have been updated to reflect the impact of the weekend storm. Many water level increases recorded yesterday were temporary and resulted mainly from high winds, with some flows from weekend storm precipitation.
Flood warnings have been issued for the Souris River from Melita and all downstream reaches; the Assiniboine River downstream of Shellmouth Bridge to Portage la Prairie; the Pipestone Creek, all reaches; Oak Lake and Plum Lakes; and the Plum Creek to the Souris River (including the town of Souris).
Flood watches are in place for the Assiniboine River downstream of Portage la Prairie and the Qu’Appelle River in the St-Lazare area.
Overland flooding is expected in areas that had significant precipitation.
Red River water levels south of Winnipeg are the sixth highest in recorded history.
The Red River is cresting in St. Adolphe and just south of the floodway inlet today. Sustained high flows are expected for a prolonged period along all reaches of the river.
The forecast peak for the Red River at James Avenue in Winnipeg is May 4 to 5 and is forecast to reach between 19.5 and 20 ft.
Water levels on the Assiniboine River at the First Street Bridge in Brandon are 1,179.26 ft., increasing 0.36 ft. since yesterday. Water levels at Brandon will continue to increase as they approach the prolonged crest, with the crest forecast between May 11 to 13. Water levels in Brandon are now the second highest in recorded history (since 1906), surpassed only by 1923 peak water levels. Flood protection dikes in the area are at 1,184 ft., well above the upper range of the forecast peak of 1,181.2 ft.
Some streams affected by high-elevation snowfall will see another peak, with water levels expected to stay within stream banks.
Flood Response
As a precautionary measure, 14 people were evacuated yesterday from their homes outside the ring dike in the St-Lazare area due to loss of road access along PTH 41. There is 3.5 feet of freeboard remaining on the St-Lazare community ring dike. The village has set up a local reception centre at 319 Main St. to register evacuees.
Across Manitoba, there are 1,914 people evacuated from their homes, in most cases because of loss of safe road access.
In Brandon, the super-sandbag dikes along 18th Street are being monitored and pumps are working to remove seepage from around the dikes. It is normal to have seepage around temporary sandbag dikes. The super-sandbag dikes across the intersection at 18th Street and PR 459 are being reinforced with another layer of bags to provide additional protection from seepage.
High winds on Saturday created four to five ft. waves along the Oak Lake dike. A 300-metre section of dike has been overtopped and ice pileup has resulted in some damage to cottage decks.
Community ring dikes in the Red River valley, the dikes along the Assiniboine River between Portage la Prairie and the Baie St. Paul Bridge, and the temporary dikes between the bridge and Headingley are being inspected today to assess any damage caused by precipitation and high waves from the weekend storm. There are no reports of any problems, however some dikes may have experienced erosion and will be reinforced if required.
MTS has restored local and long-distance telephone service to six communities. Flooding caused a bank collapse along the Pembina River and severed an MTS fibre-optic cable. This limited local and long-distance phone service including 911 emergency services. MTS worked through the night to make repairs. The affected communities included Swan Lake, Crystal City, Somerset, Pilot Mound, Mariapolis and Snowflake.
There are 91 provincial roads affected by flooding, with 62 closed. There are approximately 650 municipal roads closed.
There are currently 19 rural municipalities with states of local emergency declarations in place, down from a high of 33 on April 22.
Red River
Water levels on the Red River at Morris have declined 0.2 ft. since yesterday to 779.1 ft.
Water levels just upstream of the floodway inlet are 764 ft., with flows of 75,000 cubic feet per second (cfs). Flows in the floodway are approximately 34,800 cfs. Water is now moving through the west notch of the floodway’s east embankment, which was lowered in 2009 to improve the movement of water into the floodway.
Water levels at James Avenue in Winnipeg have increased 0.27 ft. since yesterday to 19.28 ft. Flows at James Avenue this morning were approximately 57,510 cfs. In the absence of flood- protection works, water levels at James Avenue would have been 30.7 ft. or approximately 11.4 ft. higher than current levels. Current flows without flood protection would be 111,000 cfs, which is higher than peak natural flows at James Avenue in 1950, 1979 and 1996.
Water levels on the Red River in Selkirk at PTH 4 increased 0.18 ft. since yesterday to 722.59 ft.
Assiniboine River
Water levels on the Shellmouth Reservoir have increased by 0.36 ft. since yesterday to 1,412.37 ft. Inflow into the Shellmouth Reservoir has decreased to approximately 13,120 cfs. The Shellmouth Dam will be operated to limit outflows to 10,000 cfs today and for the next few days.
Flows in the Portage Diversion channel this morning were at 21,100 cfs. Inflow upstream of Portage la Prairie is 38,100 cfs. Flows on the Assiniboine River downstream of the diversion are approximately 17,000 cfs. Flows on the Assiniboine River downstream of the diversion will gradually increase to 18,000 cfs today.
Souris River
The Souris River is now declining at all reaches, however, the precipitation from the recent storm may somewhat increase flows on the river. Despite the anticipated increase from the storm, any new crest for the Souris River is expected to be below recent peak levels.
Other Major Waterways
Lake Manitoba water levels have risen to 813.88 ft., increasing 0.02 ft. since yesterday. Outflows from Lake Manitoba were recorded at 11,800 cfs late yesterday. The Fairford Dam, at the outlet of Lake Manitoba, is operating at full capacity.
Ice pileup has occurred on the west shore of Lake Winnipeg’s south basin. Shorelines at the Willow Island area and near Gimli were affected, but no major damage was reported.
The risk of ice pileup is medium on Lake Winnipeg (south basin) and Pelican Lake. It is low on Dauphin Lake, Lake Manitoba, Lake Winnipegosis, Lake St. Martin, Rock Lake, Red Deer Lake, and North, East and West Shoal Lakes.
For more information, see www.manitoba.ca/flooding. The most up-to-date highway information is at www.gov.mb.ca/mit/roadinfo or 1-877-MBRoads (1-877-627-6237) and on Twitter by following @MBGov.
