There is a low to moderate risk of flooding this spring in southern Manitoba.

Today, Manitoba Infrastructure and Transportation (MIT) released its February spring flood outlook. It says the risk of spring flooding is largely dependent on weather conditions from now until the spring melt.

At this time, MIT's Hydrologic Forecast Centre is indicating a moderate risk of flooding along the Red and Assiniboine rivers. According to the Forecast Centre, with favourable weather conditions, the risk of flooding is low along the Red River. Levels would be similar to spring peak levels observed in 2018 from Emerson to the Red River Floodway Inlet. With normal weather, the risk of flooding is low to moderate, with levels near the spring peak observed in 2017 from Emerson to the Red River Floodway Inlet. And, with unfavourable weather, there is a moderate risk of significant flooding, with levels along the Red River main stem being similar to 2019/2020 from Emerson to Red River Floodway Inlet. 

The risk of spring flooding is generally low along several other rivers including the Roseau and Rat. Water levels are expected to remain below community flood protection levels. 

There is also a low risk of flooding for most other Manitoba basins including the Whiteshell lakes. Most Manitoba lakes, including Lake Winnipeg and Lake Manitoba are projected to remain within operating ranges after the spring run-off. 

The Department of Infrastructure and Transportation, through a contract with Winnipeg Environmental Remediations Inc., is conducting normal spring ice-cutting and breaking work along the Red and Icelandic rivers to reduce ice-jam-related flooding. Ice cutting and breaking is currently underway on the Red River north of Winnipeg and is expected to be completed by March 14. Ice-cutting and breaking work on the Icelandic River is scheduled to start March 17. This work is not being undertaken this spring on the Assiniboine River, along the Portage Diversion, due to a lower risk of ice-jam-related flooding. 

The centre also reports that operation of the Red River Floodway is expected this spring under unfavourable future weather conditions to reduce water levels within the city of Winnipeg with some operation of the Portage Diversion also anticipated to prevent ice jamming on the Assiniboine River. 

The Forecast Centre considers a few major factors when preparing its flood outlook, including soil moisture at freeze-up, winter precipitation and soil frost depth. It says due to normal to below normal summer and fall precipitation, the soil moisture at freeze-up is normal to below normal for most Manitoba basins. 

Winter precipitation has been generally below normal in most central and southern Manitoba basins, with the exception of southeastern Manitoba which has received near-normal precipitation. The United States portions of the Red River and Souris River basins also received normal to above normal precipitation since November 1st.

When it comes to soil frost depth, generally, deeper than normal frost depth means the soil absorbs less water and contributes to increased surface runoff; whereas shallower than normal frost depth means the soil can absorb more melting surface water and can potentially decrease the amount of overland flooding. The frost depth is variable across the watersheds but is generally 
considered to be normal to shallower than normal throughout most of the province due to warmer-than-normal winter temperatures.

Meanwhile, most parts of southern Manitoba and the U.S. portion of the Red and Souris River basins are forecasted to receive less than five millimetres of precipitation in the next seven days. In the longer range, climate outlook issued by the International Research Institute (IRI) at the Columbia Climate School indicates a higher chance for near-normal to above-normal precipitation in southern and central Manitoba for March, April, May, and June.

The next flood outlook is anticipated to be released in late March.