FLOOD REPORT FOR

April 29, 2018 – 9:00 am

Summary  Flows are increasing on the River upstream in Saskatchewan. Forecasting staff from Manitoba and Saskatchewan are coordinating and a forecast for the in Manitoba will be available soon.

 The Portage Diversion remains closed since there is no longer a risk of ice jamming along the lower and is not expected to be used this season. As of this morning, flow on the Assiniboine River downstream of the diversion is approximately 8,574 cfs (242 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.

Red River Basin  Flows on the Canadian portion of the Red River are continuing to rise but water levels remain within bank. 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.

 The water level at James Ave is 15.4 feet. The water level at James Avenue in Winnipeg is expected to crest between April 30 and May 2 at 16 to 17 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 1395.3 feet. Inflows into the reservoir are approximately 5,650 cfs (160 cms) and outflows are 1,377 cfs (39 cms).

 Most tributaries along the Assiniboine River appear to have crested and are beginning to decline.

 Inflows to the Portage Reservoir this morning were recorded at 8,581 cfs (242 cms). The Portage Diversion remains closed since there is no longer a risk of ice jamming along the lower Assiniboine River and flows on the river are below 10,000 cfs (283 cms). As flows increase upstream of the diversion, there will be a gradual increase in flows along the lower Assiniboine River. Flows on the Assiniboine River just upstream of Portage la Prairie are likely to reach between 9,500 and 10,000 cfs (269 and 283 cms) at the peak in early May.

 As of this morning, flow on the Assiniboine River downstream of the diversion is approximately 8,574 cfs (242 cms). Ice has moved out along the lower Assiniboine River.

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 completely ice covered.

The Pas and Northern Manitoba  The winter ice on the Carrot River near The Pas remains in place. The winter ice on the Saskatchewan River is beginning to open up and move.

 Flows are increasing on the Saskatchewan River upstream in Saskatchewan. The Tobin Reservoir on the Saskatchewan River is expected to rise to spillway level today 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 6,931cfs (196 cms) and are continuing to decrease. Forecasted peak Red Deer Lake water levels are expected to cause no flooding problems.

Manitoba Lakes  Generally, significant cover is reported on all major Manitoba lakes (50-70% 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 5,428 cfs (153 cms).

 With the exception of Lake St. Martin and 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 on the Manitoba Lakes, Morning Conditions Report (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.