Barring a large snowfall or heavy spring rains, the flood potential in most areas of southern Manitoba is low to moderate this year.
In their first flood briefing of 2014, provincial officials said the outlook looks fairly positive at this point because of a relatively "dry" snow pack and average soil moisture conditions heading into freeze-up.
At this point, the province expects that Highway 75 will remain open throughout the spring and the Shellmouth Reservoir is unlikely to overflow.
The one worry is what could happen if very cold temperatures persist followed by a rapid melt atop frozen soils.
The frost this year extends to between a metre and a metre-and-a-half below the surface of the soil, said Steve Topping, the province’s executive director of hydrologic forecasting and water management.
"What’s interesting this year is the temperature of the soil is much colder than normal. It’s minus-seven degrees Celsius, and generally it tends to be closer to minus-two degrees Celsius," Topping said.
"(With) a fast runoff and strong ice, we could have a predominance of ice-jamming in the province," he said.
Officials warned that the magnitude of a spring flood is still dependent on weather conditions from now until the spring melt. A delayed thaw and the potential for spring rainstorms could result in rapid snow melt, aggravating overland flooding and increasing the flows of tributaries.
On major rivers, including the Red and Souris, flows are generally normal or near normal for this time of year.
Assiniboine River flows are slightly above normal for this time of year due to releases from the Shellmouth Reservoir.
The Amphibex icebreakers and ice cutters will be focusing this year’s ice-jam-mitigation program on the north Red, Assiniboine, Icelandic, Brokenhead and Fisher rivers, as well as the Portage Diversion, to reduce the potential of ice jams. The Amphibex fleet has already broken a six-kilometre channel down the centre of the Red River and 12 km of ice has been cut. The chances of minor localized flooding due to snow blockages in drains, ditches and small streams during the early part of the run-off period will depend on the nature of the spring breakup and rate of melt, the province said.
Major Interlake rivers, such as the Waterhen and Fairford, are above normal due to the consistently high water levels of Lake Winnipegosis.
The Red River has thicker-than-normal ice cover due to periods of well-below freezing temperatures this winter. Based on mid-February measurements this year, ice thickness ranged between 36 centimetres (14.2 inches) and 83 cm (32.7 in.). Normal ice thickness varies according to the size and the location of the river and typically ranges between 30 cm (one foot) and 61 cm (two feet).
Most major lakes are higher-than-normal elevations right now.
Lake Manitoba, Lake Winnipeg and Dauphin Lake are listed as slightly above normal. Lake St. Martin is 3.5 feet above normal, while Lake Winnipegosis is two feet above normal and
The Shoal Lakes are 4.2 feet above normal.