Water levels increased significantly yesterday on streams in the Dauphin Lake Basin. The Valley River increased 3.25 feet. The Vermillion River increased six ft. and Wilson Creek increased 3.63 ft. The Turtle River increased 1.3 ft. and the Swan River increased 1.87 ft., as a result of snowmelt run-off. It is anticipated that Dauphin Lake will be near flood stage over the next few days and is forecast to reach a peak water level of 858.2 ft. A flood warning has been issued for Dauphin Lake and all in-flowing streams.
Many tributaries and drains on the west side of Lake Winnipegosis are at or above capacity. A flood warning for streams influenced by snowmelt in the Duck Mountains has been issued.
The Red River has reached an open-water crest of 19.56 ft. at James Avenue in Winnipeg. The open water crest is lower than the April 7 ice-influenced crest at 20.79 ft. Water levels at James Avenue in Winnipeg have increased 0.07 ft. since yesterday to 19.56 ft. Flows at James Avenue this morning were approximately 58,600 cubic feet per second (cfs). The current flow at James Avenue would be enough to fill an Olympic-size swimming pool every two seconds.
In the absence of flood-protection works, water levels at James Avenue would have been 31 ft. or approximately 11.4 ft. higher than current levels. Current flows without flood protection would be 114,000 cfs, which is approximately 6,000 cfs higher than peak natural flows at James Avenue in 1950 and 14,000 cfs below peak natural flows reached in 2009.
The Assiniboine River forecast has been revised to include increased flows from the recent storm and current conditions. As a result of this re-analysis, flows on the Assiniboine River at Brandon are predicted to be close to 26,000 cfs.
Water levels on the Assiniboine River at the First Street Bridge in Brandon are 1,179.26 ft., increasing 0.21 ft since yesterday. The peak is forecast to occur between May 11 and 13 and reach between 1,180 and 1,181.2 ft.
Water levels on local streams in areas with snowmelt are experiencing an additional crest.
The recent storm resulted in significant snow accumulation in the lower Qu’Appelle River watershed, Riding Mountain National Park and north to the Duck Mountain area. Dramatic temperature rises in the last few days have caused significant run-off into the Assiniboine River and Dauphin River Basin streams.
Flood warnings have been issued for streams and rivers in the Dauphin Lake Basin; streams and rivers east of the Duck Mountains; 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; Plum Creek to the Souris River (including the town of Souris); and the Qu’Appelle River in the St-Lazare area.
A flood watch is in place for the Assiniboine River downstream of Portage la Prairie.
Flood Response
At Eriksdale, one of the town’s lift stations was overwhelmed and caused some flooding underneath the Eriksdale Hospital and personal-care home, the public library and a home. The water has been pumped out and damage is being assessed. No evacuations are required at this time. The library and hospital are open while the assessment is underway.
Cottages around Lundar Beach have been sandbagged and large flood-barrier tubes will be provided to add additional protection as required.
At the O-Chi-Ko-Sipi First Nation near the Crane River on Lake Manitoba, adjacent to the RM of Alonsa, preparations for sandbagging are underway. The province is also sending a sandbag machine to assist with flood-fighting preparations.
Permanent dikes are expected to be in place in the next three days at the Sioux Valley First Nation.
Flood-protection systems such as the Shellmouth Dam and the Portage Diversion will be in operation for an extended period of time to deal with high water levels for several weeks. Many areas of the province including Lake Manitoba, Lake Winnipeg and the Red River from the floodway control structure to Lake Winnipeg are below the state of nature, meaning that current water levels in these areas would be higher without these flood-management systems.
There are 1,845 evacuations of Manitobans so far, largely due to loss of road access. Six additional people have been evacuated from their homes near St-Lazare due to a loss of road access. These homes are outside of the community ring dike. So far, 23 people have been evacuated from the Village of St-Lazare.
There are 97 provincial roads affected by flooding, with 61 closed. There are 630 municipal roads closed.
Red River
Water levels just upstream of the floodway inlet are 764.08 ft., with flows of 75,200 cfs. Flows in the floodway are approximately 35,300 cfs.
Water levels on the Red River downstream of the Selkirk town bridge decreased at all points today, likely declining due to south winds in the area.
Assiniboine River
Water levels on the Shellmouth Reservoir have increased by 0.5 ft. since yesterday to 1,413.33 ft. Inflow into the Shellmouth Reservoir is approximately 14,320 cfs. The Shellmouth Dam will be operated to limit outflows to 10,000 cfs today.
Water levels at all points upstream of Brandon have reached record levels and are expected to increase further before cresting.
Flows in the Portage Diversion channel this morning were at 19,500 cfs. Inflow upstream of Portage la Prairie is 37,400 cfs. Flows on the Assiniboine River downstream of the diversion will be held at 18,000 cfs for an extended period of time.
Souris River
Water levels at Melita increased 0.15 ft. to 1,410.51 ft. since yesterday. Despite the increase in water levels from the storm, any new crest for the Souris River is expected to be below all previous peak levels.
Plum Creek, a western tributary of the Souris River, is near its crest at 1,374.87 ft, increasing 0.18 ft. since yesterday.
Other Major Waterways
A high water advisory is in effect for all major lakes in Manitoba. Lake Manitoba and Lake St. Martin are forecast to reach unprecedented high water levels since regulation of the lakes in 1961. Manitoba Water Stewardship will be monitoring weather conditions closely and will provide warnings to notify of strong winds which could cause significant wind set-up and wave action. Maps will be created to indicate wind-eliminated flood levels in parts of Lake Manitoba and Lake St. Martin to help landowners prepare for high water levels. It is advisable the public make flood preparations suitable to these forecast high water levels.
Forecasters have estimated peak wind-eliminated water levels for Lake Manitoba and Lake St. Martin. Lake Manitoba water levels are forecast to reach between 814.2 and 814.6 ft. around June 4.
Water levels are forecast to reach between 804.2 and 804.6 ft. around July 1 on Lake St. Martin. These elevations are preliminary at this time and may be revised with major weather changes and as computer models are refined.
Lake Manitoba water levels have risen to 813.99 ft., increasing 0.09 ft. since yesterday. Lake St. Martin water levels have risen to 803.36 ft., increasing 0.07 ft. since yesterday.
Outflows from Lake Manitoba were recorded at 12,420 cfs late yesterday.
Ice on parts of Lake Manitoba has broken and open water is visible on the northern half of the lake’s south basin. The risk of shoreline ice pileup today is high on Lake Manitoba and Lake Winnipeg, and low on all other assessed 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.
