The controlled release at the Hoop and Holler Bend is still diverting around 400 cubic feet per second (cfs) from the Assiniboine River. As planned, water continues to move east into the Elm River and eventually into the La Salle River.
At the time of the controlled release, the Assiniboine River dikes were weak in 16 or 17 spots and there was a very real and imminent concern of an uncontrolled breach. In addition, at that time, the work necessary to expand the Portage Diversion’s maximum capacity to 34,000 cfs had just been completed. The controlled release capacity was necessary to provide a margin of safety in case the diversion was not able to handle 34,000 cfs for a long enough period of time.
Better weather and the work of government and military personnel has helped with the reinforcement of the dikes but the dikes are still vulnerable. Today, the crews that are continuously monitoring and addressing issues on the dikes and the Portage Diversion Channel found a new area of concern and are following up accordingly. Approximately eight homes close to the area of concern are being evacuated.
Until the second crest has passed the Portage Reservoir, there is still a need to divert flows through the controlled release to provide as much relief as possible to the Portage Diversion channel. The Portage Diversion has been operating beyond its design capacity for quite some time and there is a continued need to protect the integrity of the system.
Flows through the controlled release have remained at the low end of the initial estimate and this has helped reduce the impact in the area affected by the release.
The day the controlled release was made, inflows at the Portage Reservoir reached 52,300 cfs and the river downstream of the controlled release was at the maximum flows it could handle at that time of 18,000 cfs. This required at least 300 csf to be removed off the diversion channel as the new, temporary capacity of the channel is a maximum of 34,000 cfs.
The initial forecast for inflows into the Portage Reservoir included the chance of unfavourable weather and the possibility that all tributaries might not drop off as quickly as expected. This information was included in the forecast due to the very high potential for a catastrophic uncontrolled breach along the Assiniboine River dikes and the effect unfavourable weather and high tributary flows could have on this possible scenario.
Government staff continues to call affected property owners in the controlled and uncontrolled release zones as well as along Lake Manitoba to provide them with information and updates about the flooding situation. As of today, approximately 2,000 calls have been made.
Lake Manitoba
The RM of Siglunes is sandbagging 140 at-risk homes because of some overland flooding and high levels on Lake Manitoba.
The RMs of St. Laurent and Woodlands have issued a precautionary evacuation alert for at-risk homes and are undertaking flood-protection measures in the area. A large stockpile of sandbags has been sent to the area.
A provincial sandbagging machine and 150,000 sandbags have been delivered to the RM of St. Laurent and approximately 66 government employees are in the area assisting with sandbagging.
A total of 50,000 sandbags have been sent to the RM of Woodlands.
The RM of Coldwell has received 86,000 sandbags and 500 metres of flood tubes.
The RM of Siglunes has been sent 70,000 sandbags and one large pump to assist in their flood-fighting efforts.
Manitoba Agriculture, Food and Rural Initiatives continues to work with producers in the Lake Manitoba area to address their immediate and long-term issues.
Provincial staff will be hosting meetings with representatives from municipalities, First Nations and Northern Affairs communities located around Lake Manitoba and Lake St. Martin. Forecast peak lake levels will be presented to enable representatives to make necessary flood preparations and assistance with interpreting flood maps and other forecast information will be provided.
Evacuations
There are currently 3,354 people evacuated due to flooding. Of this number, 1,391 are from the city of Brandon.
Well-water Safety
Evacuated residents in the Red River valley and other areas are beginning to return home. As a precautionary measure, the Office of the Chief Public Health Officer has issued a boil water advisory for those using private, untreated water sources, such as well water or surface water for drinking water in flood-prone areas.
The Manitoba government will once again cover the costs of testing drinking water supplies once flooding has ended. Details about free testing and well-water safety are available on the flood website at www.manitoba.ca/flooding.
Disaster Financial Assistance
The disaster financial assistance (DFA) program will assist Manitobans who suffer private property losses or damages from spring flooding. Assistance is provided to help homeowners, tenants, farmers, small-business owners, non-profit organizations and municipal governments to restore property after a disaster.
More detailed information about DFA is available at www.gov.mb.ca/flooding/dfa.html.
For property owners affected by the controlled release along the Assiniboine River dikes, a special comprehensive compensation program is being developed and details will be available shortly.
Flood Forecast Summary
Inflow upstream of Portage la Prairie is 51,930 cfs. Flows in the Portage Diversion channel this morning were at 33,380 cfs. Flows on the Assiniboine River at the Portage Reservoir control gates were 18,500 cfs.
Flows into the Portage Reservoir are forecast to crest today at approximately 52,000 cfs. After today, flows are forecast to subside by approximately 1,000 cfs per day over the next few days, then reduce by 1,700 cfs per day in the following days.
The forecast peak for Lake Manitoba is 815.8 ft. The forecast peak for Lake St. Martin is 805.2 ft.
A high water advisory remains in effect for all major lakes in Manitoba.
Water levels on the Assiniboine River at the First Street Bridge in Brandon were 1,181.68 ft., a decrease of 0.52 ft. since yesterday. Flows at the First Street Bridge in Brandon were 34,165 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.
Flood warnings remain in effect for the Qu’Appelle River in the St-Lazare area; the Assiniboine River at all points downstream of the Shellmouth dam; all reaches of Pipestone Creek and downstream into the Oak and Plum Lake system; and on Plum Creek to the Souris River including the town of Souris.
Assiniboine River
Water levels on the Shellmouth Reservoir dam were 1,413.87 ft., with no change since yesterday. Inflow into the Shellmouth Reservoir has decreased to 10,020 cfs and outflow is to 10,020 cfs today. The Shellmouth Reservoir will be operated to keep flows around 10,000 cfs today and for the next few days.
Water levels at St-Lazare are 1,288.96 ft., a decrease of 0.19 ft. St-Lazare’s community flood protection level is 1,295.36 ft.
Water levels in the Baie St. Paul area are 799.9 ft., a decrease of 0.01 ft. since yesterday. Water levels at Lido Plage are 780.28 ft., decreasing 0.07 ft. since yesterday.
Lakes
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.
Oak Lake continues to rise due to high inflows from the Pipestone Creek. Water continues to overtop dikes by as much as two ft. in some places. Plum Lake, located downstream of Oak Lake, is also reaching high lake levels and continues to contribute high flows to Plum Creek. See the table for lake levels.
Dauphin Lake has reached a record water level and is forecast to continue rising.
Red River and Floodway Operations
The north entrance at St. Adolphe remains closed. The south entrance is open.
Water levels just upstream of the Red River floodway inlet decreased 0.37 ft. since yesterday to 760.93 ft., with flows of 56,600 cfs. Flows in the floodway channel are approximately 23,900 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 0.11 ft. since yesterday to 17.9 ft. Flows at James Avenue this morning were approximately 51,500 cfs.
Souris River
Water levels at Melita were 1,410.06 ft. today, increasing 0.08 ft. since yesterday. The flood warning for the Souris River at Melita and all downstream reaches has been downgraded to a high water advisory.
Flows on Pipestone Creek have decreased to 3,400 cfs. Water levels in Oak Lake are 1,412.27 ft. Water levels on Plum Creek are 1,377 ft. today. 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 0.13 ft. since yesterday to 1,155.93 ft. today.
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.
