Archived News Releases

Media Bulletin - Manitoba

May 17, 2011

Flood Bulletin #51

Flood Response

Controlled Release

  • Approximately 400 cubic feet per second (cfs) is currently going through the controlled release point.  The release is relieving pressure on flood-control systems between Portage la Prairie and Headingley.
  • Before the controlled release, there were as many as 17 soft spots leaking along the Assiniboine River dikes.  The efforts of provincial staff with the support of over 1,000 military personnel have shored up the dikes substantially.  Warm temperatures and sunshine this week are helping to dry out wet, muddy areas making it easier to work and helping to strengthen the dikes. 
  • To support the work on the dikes, the Portage Diversion was strengthened and reinforced to take additional flows.  The controlled release point has relieved some pressure and helped protect against an uncontrolled breach of the Assiniboine dikes and the Portage Diversion structures and dikes which could flood a large area of the region.
  • The basement of one home has taken on water in the controlled release area.  Although the home has no water around it, a septic pipe and a sump pump may have failed.  The homeowner has been contacted. 
  • There has been some damage to garages and fences in the controlled release zone.  Three homes have water around them, but their flood-protection systems are holding.
  • The Manitoba government is developing a comprehensive compensation program for homeowners and producers.

Controlled Release Area Flood Forecast

  • Flows out of the release will be maintained at around 400 cfs today, depending on conditions of the Assiniboine River dikes and Portage Diversion channel.  Flows from the release are generally pooling between mile roads 32 and 33W then entering the Elm River.  As of last night, the flooded area covered an area of 2.7 square kilometres.  Flows will travel down the Elm River with some localized flooding in adjacent areas
  • Flows into the Portage Reservoir are forecast to crest around today and tomorrow at approximately 52,000 cfs.  High flows are expected to be sustained for two to three days beyond the crest and then slowly subside by approximately 500 cfs per day.  
  • Inflow upstream of Portage la Prairie is 51,350 cfs.  Flows in the Portage Diversion channel this morning were at 32,950 cfs.  Flows on the Assiniboine River at the Portage Reservoir control gates were 18,400 cfs.
  • With flows through the controlled release around 500 cfs to 1,000 cfs, levels in the La Salle River at Elie would be slightly elevated, with minor backwatering south of Elie. 
  • The capacity of the La Salle River near the communities of La Salle, Sanford and Starbuck is generally in the order of 4,000 cfs and slightly higher in downstream reaches.  Approximately 300 cfs is flowing in the La Salle River at Sanford today. 

Lake Manitoba

  • Provincial staff will be hosting meetings with representatives from municipalities, First Nations and Northern Affairs communities located around Lake Manitoba and Lake St. Martin.  Forecasted peak lake levels will be presented to enable representatives to make necessary flood preparations.  Meetings are currently being co-ordinated.  Dates and locations will be provided within the next few days.
  • In the RM of St. Laurent, a provincial sandbag machine has been producing approximately 15,000 sandbags per day.  The RM has already contracted for a second sandbag machine.  Each cottage or home in the area will be surveyed and information about protection levels will be provided over the next few days.  The RM has also issued information about evacuations to area residents and established its emergency operation centre.  Approximately 55 Manitoba government employees will be sent to the RM tomorrow to assist with sandbagging efforts.  This effort will continue over the next three days.


  • In Brandon, First Street will open to northbound traffic only today.
  • Dikes continue to hold and are being closely monitored.
  • There are 1,383 people out of their homes in Brandon as part of a precautionary evacuation.

Other Areas

  • A provincial call centre is in place and making regular contact with residents in the area affected by the controlled release.  Residents are being provided information about the release, potential water levels for their homes and the area, and where to access additional information.  In addition, door-to-door teams are working in the area.  Over 1,400 calls have been made to residents in the controlled, uncontrolled and Lake Manitoba area.  Residents can also call 204-945-7200 and
    toll-free at 1-855-679-3802.
  • Additional homes are being sandbagged around the Oak Lake and Plum Lake area, which continues to be at flood stage due.
  • The Pinaymootang First Nation (Fairford) has established a facility for approximately 400 residents affected by flood waters in an arena in a part of the community that is high enough to remain dry.  The facility has been set up with the support of the Manitoba Association of Native Firefighters, Red Cross and Manitoba government departments. 
  • Manitoba Agriculture, Food and Rural Initiatives has been working with the Lake Manitoba First Nation to deal with a cattle herd that was becoming isolated by high water levels.  The majority of the herd has been successfully rescued and moved with the combined efforts of the community and the department.
  • PTH 75 is now open from Winnipeg to the U.S. border.
  • There are 1,700 Canadian Forces personnel helping with flood-fighting efforts in Manitoba.
  • There are 113 provincial roads affected by water and there are 663 municipal roads closed.

Flood Forecast Summary

  • Flood warnings have been issued for the Assiniboine River at all points downstream of the Shellmouth Dam; 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 high water advisory is in place for all major lakes in Manitoba, the community of Red Deer Lake, streams and rivers in the Dauphin Lake basin; streams and rivers east of the Duck Mountains; and  the Souris River from Melita and all downstream reaches.


  • Natural water levels are defined as lake levels that would occur if there were no flood-control works in place.  In early April and before the flood, water levels in Lake Manitoba were approximately two feet lower than what would have occurred naturally.  Lake St. Martin water levels were one ft. above natural water levels.
  • Lake Manitoba water levels have been calculated for natural conditions.  Natural conditions are based on there being no inflows into Lake Manitoba from the Portage Diversion and the Fairford Dam and expanded Fairford River channel.  These flood-control works are operated to keep levels on Lake Manitoba from exceeding those that would be experienced under natural conditions.  If natural conditions were in place, it is estimated that today, levels on Lake Manitoba would be approximately 1.1 ft higher.
  • The flows entering Lake Manitoba from the Portage Diversion are temporary and will be reduced once Assiniboine River water levels subside.  Flows out of Lake Manitoba through the Fairford River will continue to be at maximum discharge throughout the summer and fall.
  • Due to increased outflows from the Fairford River, Lake St. Martin water levels are above natural levels by approximately 2.1 ft. today.  Outflows from Lake St. Martin flow down the Dauphin River to Lake Winnipeg.
  • The south winds will help reduce wind setup and wave action along the southern boundary of Lake Manitoba, Lake Winnipeg and Dauphin Lake.  Winds for Pelican/Rock Lake, Oak Lake and the Shoal lakes will be southeast 25 km/h today.  See table below for lake levels.


Level1 (ft.)

Change from Last Reading (ft.)

Date of Last Reading

Lake Manitoba



May 16

Lake St. Martin



May 16

Lake Winnipeg



May 16

Lake Pineimuta



May 16

Dauphin Lake



May 16

Oak Lake



May 16

North Shoal Lake



May 14

East Shoal Lake


no change

May 14

West Shoal Lake



May 14

Red Deer Lake


no change

May 15

 1Wind-effect eliminated            2Reading may be influenced by wind 
  • Yesterday’s revised forecast peak for Lake Manitoba was set at 815.8 ft.  The revised forecast for Lake St. Martin was set at 805.2 ft. 
  • Due to high water levels, Manitoba Water Stewardship has created inundation maps illustrating the forecast high water levels for all areas around Lake Manitoba, parts of Lake St. Martin and developing maps for the south basin of Lake Winnipeg. 

Assiniboine River

  • The volume of water flowing through the Assiniboine River at Brandon between April 1 and
    May 15 is higher than all previous years in recorded history.
  • Water levels on the Shellmouth Reservoir are 1,413.87 ft., decreasing 0.23 ft. since yesterday.  Inflow into the Shellmouth Reservoir has decreased to 7,950 cfs and outflow decreased to
    10,020 cfs.  Outflows from the Shellmouth Dam will be increased to 11,000 cfs to bring water levels below spillway elevation in the coming weeks.  It is important to have reservoir storage for late spring run-off or early summer precipitation events to minimize flooding on surrounding agricultural lands, residences and downstream communities.
  • Water levels on the Qu’Appelle River at Welby decreased 0.18 ft. since yesterday to 17.57 ft.  Flows on the Qu’Appelle River are estimated at 8,300 cfs today. 
  • Water levels at St-Lazare are 1,289.14 ft., a decrease of 0.1 ft.
  • Water levels at Sioux Valley are 1,203.81 ft., increasing 0.06 ft. since yesterday.  Dikes at the Sioux Valley First Nation are providing flood protection to 1,207 ft. 
  • Water levels on the Assiniboine River at the First Street Bridge in Brandon are 1,182.2 ft., a decrease of 0.51 ft. since yesterday.  Flows at the First Street Bridge in Brandon were 35,100 cfs, measured this morning.  It is estimated that flows on the Assiniboine River at Brandon will be sustained above 20,000 cfs for approximately two weeks.

Red River

  • Water levels just upstream of the Red River floodway inlet decreased 0.66 ft. since yesterday to 761.30 ft., with flows of 58,300 cfs.  Flows in the floodway channel are approximately 25,200 cfs.  Red River flows upstream of the floodway inlet continue to decrease by about 2,000 cfs per day.
  • Water levels on the Red River at James Avenue in Winnipeg have decreased 0.12 ft. since yesterday to 18.01 ft.  Flows at James Avenue this morning were approximately 51,900 cfs. 
  • With flows through the controlled release around 500 cfs to 1,000 cfs, levels in the La Salle River at Elie will be slightly elevated, with minor backwatering south of Elie.  Water will reach the communities of La Salle, Sanford and Starbuck after Elie.

Souris River

  • Water levels at Melita are 1,410.06 ft. today, increasing 0.08 ft. since yesterday. 
  • Flows on Pipestone Creek have increased to 4,380 cfs and will crest for a third time.  Water levels in Oak Lake are 1,412.24 ft.  Water levels on Plum Creek have increased by 0.02 ft. since yesterday to 1,372.28 ft.  These high flows will continue and be sustained for a significant period of time due to the high levels of the Plum and Oak lakes. 
  • Water levels on the Souris River at Wawanesa decreased to 1,156.06 ft. today, 1.9 ft. below the highest crest this year.

For more information, see  The most up-to-date highway information is at or 1-877-MBRoads (1-877-627-6237) and on Twitter by following @MBGov.

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