No precipitation is expected for the next five days. Significant melting will begin April 7 and will quicken by April 9 based on current weather forecasts. Snow cover in most areas of southern Manitoba should be melted by April 10. The milder weather and higher river flows next week will cause river ice to move.
Flood Forecast
• Predicted crests for the Red River have changed little. However the top of the forecast range from Emerson to St. Adolphe has been reduced by 0.15 m (half a foot). The forecast is being reviewed and updated on a daily basis.
• The U.S. National Weather Service has indicated that a second crest is possible at some U.S. locations on the Red River if adverse weather conditions develop. It is very unlikely that a second crest would occur in the Manitoba portion in late April or May, but the possibility exists if heavy rain develops in the coming weeks.
Winnipeg Floodway Operations:
• The floodway will operate this year as soon as ice is flowing freely at the inlet structure. However, earlier operation with ice in place may be required due to a combination of high flows and potential ice jams. If the city’s river level is predicted to exceed 6.1 metres (20 ft.) at James Avenue within a 24-hour period, the floodway will be operated as necessary to avoid imminent flooding in Winnipeg. This operation would follow the floodway’s Environment Act licence to protect the city of Winnipeg.
• Engineering staff within Manitoba Water stewardship will assess river levels on an ongoing basis and advise the minister of water stewardship when the floodway gates should be raised. The province and the City of Winnipeg are working together and have established a communications protocol and an equipment-sharing protocol regarding floodway operations. The province is providing the city with one of the recently purchased provincial trailers containing 60 15-m (50-ft.) Tiger dam tubes and 60 30-m (100-ft.) Aquadams to assist with flood fighting.
• If the floodway gates are raised with ice in place, properties south of the floodway inlet will experience a more rapid rise in river levels than otherwise expected, but these levels will not be above the predicted crest for this area of 233 m (765 ft.). Property in this area has been protected to 1997 plus 0.6 m (two ft.) levels and the rise and subsequent crest will be well below that protection. Some roads and land in this area will be flooded.
Emerson to the Floodway Inlet:
• River ice is likely to begin moving around Emerson this weekend and should move in the area from St. Adolphe to the floodway inlet by about the middle of next week.
• Crests from Emerson to the floodway inlet are expected to occur under open water conditions after the ice has moved out. Crests in this portion will be only slightly higher than those of 2006 based on favourable weather for the next 10 days. If a 25-millimetre (one-inch) rainstorm were to occur in Manitoba next week on top of snowmelt, crests could be 0.15 to 0.3 m (one-half to one ft.) below those of 1979. There is only a very small risk of ice jams raising levels to those of 1979 or higher. The crest is expected at Emerson about April 9 and at St. Adolphe about April 15.
• Levels rose 0.5 m (1.5 ft.) at Emerson and 0.27 m (0.9 ft.) at Morris during the 24-hour period ending this morning. The level at the floodway inlet this morning was 229.49 m (752.92 ft.), a rise of 0.08 m (0.26 ft.) from yesterday morning. The flow into the Red River Floodway was 1,300 cubic feet per second (cfs) of a total 36,850 cfs upstream of the floodway inlet.
City of Winnipeg:
• The river level in downtown Winnipeg fell three centimetres (one-tenth of a foot) to 5.1 m (16.6 ft.) during the 24-hour period ending this morning. Further deterioration of the ice jam north of Lockport and reduced flows on the Assiniboine River led to the decline. Rises are expected to resume in Winnipeg within a day or two and will become more rapid next week.
• Ice is expected to move out of Winnipeg and the floodway inlet area April 7 to 9. If the ice does not move until the morning of April 9, a crest of 6.25 m (20.5 ft.) could occur just prior to ice movement. This crest forecast includes the effect of minor ice jams at bridges but does not include the possibility of a serious ice jam.
• The threat of ice jamming in the city is considerable this spring due to the large number of bridges and the above-average ice strength. While ice jams have not raised river levels in the city by more than 0.5 m (1.5 ft.) in recent history, it is possible that a somewhat greater rise could occur this spring if ice jams develop.
• The crest which passed through Grand Forks last Thursday is expected to arrive in the Winnipeg area about April 16. Since river ice will be gone by that time and the Red River Floodway will be in operation, the open water crest in Winnipeg on April 16 will be about 5.6 m (18.5 ft.) which is more than 1.8 m (six ft.) lower than what the crest would be without the floodway and other flood-control works.
Lockport to Breezy Point:
• The ice jam at Lower Fort Garry continues to deteriorate, resulting in a further decline of 0.12 m (0.4 ft.) at St. Andrews Dam since yesterday. It is unlikely that levels from St. Andrews to Lower Fort Garry will again rise above those experienced last week. Winter ice is still in place from Selkirk to Breezy Point where levels have changed little since yesterday. Crests in this portion of the river will depend very much on the occurrence and severity of ice jams which are unpredictable. Reports indicate that the ice is gradually weakening. Ice in this area will likely begin moving April 7 to 10 at which time the risk of ice jams will be greatest. Ice-cutting and breaking activities have reduced the risk of serious ice jams developing and therefore it is unlikely that the extreme levels of 2007 and 1996 will be repeated. The level at Selkirk this morning is only three cm (a tenth of a foot) higher than yesterday.
Assiniboine River and Other Areas:
• The flow on the Assiniboine River at Portage la Prairie was 5,315 cfs this morning, of which 2,720 cfs was diverted into Lake Manitoba. The outflow from Shellmouth Reservoir remains at 200 cfs. Minor flooding is expected along the Assiniboine River from St. Lazare to Grand Valley, likely around Easter.
• River levels in western Manitoba and the Interlake are quite low and stable. Rises will develop next week following warmer temperatures and snowmelt.
• A potential for minor flooding still exists in the Interlake region where run-off has been delayed due to cool weather.
• 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.
Flood Response
• Ring dike communities continue to prepare for partial or full closures of their dikes potentially by early next week. It is expected PTH 75 will be closed at Morris by mid-week. Travel on PR 200 by St. Adolphe could also be restricted by mid-week. Highway conditions and alternate routes can be checked at www.manitoba.ca or by calling 204-945-3704 or 1-877-627-6237.
• The Amphibex ice breakers are undergoing routine maintenance and will then be placed on standby in strategic locations in the city to address potential ice jams starting tomorrow when the first machine will be located by the Redwood Bridge.
• Two ice cutters are currently working along the Whitemud River.
• There are 31 steamer units working in southern Manitoba. Another six will be working over the weekend bringing the total to 37. This number includes the 24 additional steamers purchased by the province to deal with frozen culverts this spring.
• The province has expedited the delivery of Aquadam flood tubes, with 1,525 m (5,000 lineal ft.) being delivered today and every day for the next four days resulting in a total of 7,620 m (25,000 lineal ft.).
Evacuations
• The Manitoba Association of Native Fire Fighters (MANFF) in consultation with Roseau River First Nation residents have undertaken a partial return of evacuees to their homes. The MANFF is co‑ordinating this return process. At this time, 481 residents remain in Winnipeg.
• A partial evacuation of 30 people on the Sioux Valley Dakota First Nation remains in place. Affected residents are in Virden. Local road access on the First Nation has been threatened by rising creek levels, but no homes have been flooded.
Road Conditions
• Once snow and ice begins to melt, road conditions can change very quickly. Before travelling in flood-prone areas, check www.manitoba.ca or call 204-945-3704 or 1-877-627-6237.
