Flood Report for Manitoba
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FLOOD REPORT FOR MANITOBA April 30, 2018 – 9:00 am Summary Flows are still increasing on the Saskatchewan River upstream in Saskatchewan. Forecasting staff from Manitoba and Saskatchewan are coordinating and a forecast for the Saskatchewan River in Manitoba will be available soon. The Portage Diversion remains closed and it is not expected to be used this season. As of this morning, flow on the Assiniboine River downstream of the diversion is approximately 8,510 cfs (240 cms). The Red River upstream of the Floodway Inlet is near crest, water levels will remain below the top of bank. The Red River Floodway will not be operated this spring. As most flows are nearing or past their peak, Manitoba Infrastructure will discontinue production of the daily flood report and associated flood products. Staff will remain in regular communication with RM Kelsey to provide condition and forecasting reports on the Saskatchewan and Carrot Rivers. Any other questions or concerns about flood mitigation should be directed to the municipal authority. Red River Basin With the exception of Emerson, flows on the Canadian portion of the Red River are continuing to rise but water levels remain within bank and the water levels are very near to cresting. Water levels on tributaries to the Red River are continuing to decline. The Red River upstream of the Floodway Inlet is near crest, water levels will remain below the top of bank. The Red River Floodway will not be operated this spring. The water level at James Ave is 15.6 feet. The water level at James Avenue in Winnipeg is expected to crest in the early part of this week, at approximately 16 feet. Assiniboine River Basin The Shellmouth Reservoir was drawn down over the winter in preparation for spring runoff; water levels are now increasing to reach the summer target level. The current water level is at 1395.97 feet. Inflows into the reservoir are approximately 5,420 cfs (155 cms) and outflows are 1,390 cfs (39 cms). Water levels on the upper Assiniboine River have crested. Minor increases on the lower Assiniboine River will continue to occur until the river peaks in early May. Inflows to the Portage Reservoir this morning were recorded at 8,510 cfs (240 cms). The Portage Diversion remains closed as ice along the lower Assiniboine River has moved out and there is no longer a risk of ice jamming. Flows upstream of the diversion are near crest. Parkland Region Flows on streams and tributaries in the Dauphin and Swan Rivers watersheds remain low and are generally declining. Dauphin Lake is reported to be 40% ice covered. The Pas and Northern Manitoba The Carrot River is mostly ice-free, some ice remains in place at the Turk Road Bridge. The winter ice on the Saskatchewan River continues to break up and is mostly open water. Flows are increasing on the Saskatchewan River upstream in Saskatchewan. Flow on the Saskatchewan River at The Pas is 43,730 cfs (1,240 cms). The Tobin Reservoir on the Saskatchewan River is expected to rise to spillway level due to high inflow volumes. Officials in Saskatchewan are preparing an operational forecast for the dam and reservoir. Forecasting staff from Manitoba and Saskatchewan are coordinating and a forecast for the Saskatchewan and Carrot Rivers in Manitoba will be available soon. Flows on the Red Deer River at Erwood, Saskatchewan are 6,670 cfs (190 cms) and are continuing to decrease. Forecasted peak Red Deer Lake water levels are expected to cause no flooding problems. Manitoba Lakes Generally, minimal ice cover is reported on all major Manitoba lakes (30-40% ice cover). The water levels on Manitoba’s major lakes are relatively stable. Once the major lakes are ice free, wind alert maps for the lakes will be produced when significant wind events are forecasted. The Fairford River Water Control Structure is being operated for maximum possible discharge; outflow from Lake Manitoba is approximately 4,775 cfs (135 cms). With the exception of Lake St. Martin and Lake Winnipegosis which are higher than average, most of Manitoba’s major lakes are near their average level for this time of year. Lake Manitoba, Lake Winnipeg and Lake St. Martin are within their desired operating range. Lake Manitoba is expected to peak around mid-May. Risk of ice pile-up is considered low, but wind forecasts will continue to be monitored. An updated lake level forecast will be provided in the next few days. Inflows into Pelican Lake remain low and lake levels are expected to remain near their current level until the occurrence of spring or summer rainfalls. Detailed information on lake levels is available online (http://www.gov.mb.ca/mit/floodinfo/index.html). *Definitions Flood Warning: A flood warning is issued when river or lake levels are exceeding or are expected to be exceeding flood stage within the next 24 hours. Flood Watch: A flood watch is issued when river or lake levels are approaching and likely to reach flood stage, but likely not within the next 24 hours. High Water Advisory: A high water advisory is issued when a heavy storm or high flows are expected and may cause water levels to rise, but not necessarily reach flood stage. A high water advisory can be an early indicator for conditions that may develop into a flood watch or flood warning. .