While the crest of the Red River is occurring in Winnipeg and the most southern areas of the Red River Valley, communities from Morris to St. Adolphe have yet to see their crests and river levels will remain high at all locations for several weeks. A high state of vigilance is still required throughout the flood zone.
Flood Forecast
Little precipitation is expected over southern Manitoba for the next five days although a few showers are likely on Sunday. The Interlake area may receive an additional five to 10 millimetres (0.2 to 0.4 inches). The U.S. portions of the Red and Souris rivers are also expected to receive little rain.
City of Winnipeg:
• The Red River in Winnipeg crested yesterday at a level of 6.9 metres (22.5 feet) at James Avenue near downtown Winnipeg. The level at James Avenue this morning was 6.6 m (21.7 ft.), a decline of 0.23 m (0.75 ft.) from the crest. The level is expected to decrease to less than six m (20 ft.) by next Tuesday.
• The prime reason for the declining levels in Winnipeg is rapidly falling flows on the Assiniboine River due to operation of the Portage Diversion several days ago, when flows down the river were reduced to just 500 cubic feet per second (cfs) of a total flow of about 20,000 cfs upstream of the diversion.
• High flows on local streams such as Sturgeon Creek and the La Salle River contributed to yesterday’s crest in Winnipeg but these streams will also be declining beginning today.
• The crest of 6.9 m (22.5 ft.) at James Avenue in Winnipeg was the second highest since major flood control works began operation in 1969. The crest was 7.5 m (24.5 ft.) in 1997.
• The natural peak within Winnipeg without provincial flood control works would be occurring today at 10.2 m (33.4 ft.) at James Avenue, over 0.9 m (three ft.) higher than the great flood of 1950. With the regulated level at James Avenue being 6.6 m (21.5 ft.) at the time of this natural peak, the Red River Floodway, Portage Diversion, and Shellmouth dam are reducing water levels in Winnipeg by almost 3.7 m (12 ft.).
Lockport to Breezy Point:
• Levels in this portion are still 0.6 to 0.9 m (two to three ft.) lower than recent crests resulting from ice jams last weekend. Levels have declined somewhat since yesterday and will continue to fall slowly for the next few weeks.
Emerson to St. Adolphe:
• The river has finally crested at Emerson and Letellier and is at its crest in St. Jean Baptiste.
• Crest forecasts from Ste. Agathe to St. Adolphe have been lowered by 10 centimetres (0.33 ft.). Additional rises of six to nine cm (2.4 to 3.5 in.) are expected from Morris to St. Adolphe. The crest is expected at Morris tomorrow and at Ste. Agathe and St. Adolphe on Sunday or Monday.
• Levels declined 0.91 cm (0.4 in.) at Emerson and rose nine cm (3.5 in.) at Morris during the 24-hour period ending this morning.
• Levels in the United States portion are declining slowly.
• So far this spring, the Red River has risen 11.2 m (36.8 ft.) at Emerson, 10.4 m (34.1 ft.) at Morris and 10.3 m (33.8 ft.) at the floodway inlet.
Floodway Inlet:
• The water level upstream of the floodway inlet this morning was 233.7 m (766.57 ft.), a rise of 21.3 cm (0.7 ft.) since yesterday morning. The flow into the Red River Floodway this morning was estimated at 41,800 cubic feet per second (cfs) of a total 93,000 cfs upstream of the floodway inlet.
Assiniboine River:
• Flow into Portage Reservoir declined from 19,880 cfs yesterday morning to 17,700 cfs this morning. A very gradual decline is expected for the next five days. The flow in the Portage Diversion this morning was 17,180 cfs and the flow in the river downstream was 520 cfs. River flows toward Winnipeg were further reduced two days ago to reduce levels in the city of Winnipeg.
• Assiniboine River levels from Baie St. Paul to Winnipeg will continue to decline quite rapidly for the next few days.
• Flooding continues along the Assiniboine River from St. Lazare to Brandon. The crest is presently in the portion from Griswold to Brandon but little further rise is expected in this portion. Valley flooding should end within a week or so if there is little rain but it will take several additional weeks of favourable weather to dry the valley.
• The outflow from Shellmouth Reservoir is at 50 cfs this morning. The water level of Shellmouth Reservoir has risen 27.4 cm (0.9 ft.) since yesterday and stood at 425.3 m (1,395.4 ft.) this morning. The level is expected to rise to at least 426.7 m (1,400 ft.) by the end of April. The normal summer level is 427.5 m (1,402.5 ft.)
Souris River:
• Levels of the Souris River in Manitoba are still rising quite slowly. Over-bank flows are still limited to the Coulter area but will spread to areas further north by late next week. A crest exceeding that of 1999 by about 0.3 m (one ft.) is expected at the end of April or in early May. Some diking will be required in the south portions of Melita and just south of Souris. Extensive agricultural flooding will occur.
Pembina River:
• Serious flooding of the Pembina Valley continues with the crest presently in the Swan Lake area where the river has overtopped PTH 34 by about 0.52 m (1.7 ft.)
• The river has risen between 0.9 to 1.2 m (three to four ft.) in the La Rivière area during the 24-hour period ending this morning. Sandbagging continues to protect buildings at the Holiday Mountain Resort where the crest is expected late today.
• Levels from Rock Lake to La Rivière will be similar to those of 1974, which was among the largest floods experienced in recent decades.
• A peak discharge of 15,000 cfs is expected at Windygates early on Sunday, exceeding the extreme crest of 2006 at this location.
• Rock Lake crested at 408.25 m (1,339.4 ft.) yesterday and had declined to 408.15 m (1,339.1 ft.) this morning. This crest is among the highest on record.
• The U.S. National Weather Service is predicting a another crest at Walhalla based on the crest now approaching Windygates and is indicating the peak stage at Neche may rise to 6.6 m (21.8 ft.) which is 12.2 cm (0.4 ft.) higher than that of 2006. Significant boundary overflows could result, especially if a strong south wind develops during the next 10 days.
• Manitoba Water Stewardship and Manitoba Infrastructure and Transportation staff are closely monitoring possible overflows at the international boundary. Actions will be taken to protect Gretna and Halbstadt from possible flooding due to overflows.
Other Rivers:
• Both the Fisher and Icelandic rivers are presently at their crest. Minor over-bank flows are occurring with flooding in low-lying areas such as the Peguis First Nation and the community of Fisher River. Flooding is expected to end by early next week.
• Extensive overland flooding continues in the Interlake region with many roads overtopped or washed out. Conditions will begin to improve next week if the weather is favourable, but some flooding will continue for several weeks.
• All tributaries of the Red River had crested as of this morning, except for areas affected by backwater from the Red River.
• The flood potential for the Westlake area is quite low. Minor localized flooding may occur late next week.
• The flood potential remains low from Swan River to The Pas.
Overland Flooding
• Overland flooding continues in many portions of southern Manitoba, especially in the Red River Valley and the Interlake and this will continue through the coming weekend but should be generally subsiding. Residents in low-lying areas are advised to take precautions against possible sudden rises.
• Further details are provided below and specific forecasted crest stages are shown on the daily flood sheets issued by Manitoba Water Stewardship.
