Preparations begin for 2013 flooding

April 8, 2013 7:54 am
Kevin Weedmark

Manitoba and Saskatchewan are on high alert for increased spring flooding potential on the Red, Souris, Pembina, Assiniboine, Saskatchewan and Qu'Appelle rivers, and in areas with heavy snow cover.

Saskatchewan's government is taking action in a number of areas to address spring flooding concerns:

The Water Security Agency launched the 2013 Emergency Flood Damage Reduction Program which provides engineering and technical assistance to municipalities while sharing the cost of permanent and temporary flood prevention works.

WSA recently launched a mobile website which will provide better access to information on stream flows, lake levels, news and advisories.

WSA will release the April spring run-off forecast update this week.

Emergency Management and Fire Safety has deployed a cache of emergency equipment to the south of the province, strategically located near areas likely to be affected by flooding.

EMFS will continue to work with communities to improve their emergency preparedness, and encourages them to prepare to activate their emergency plans and emergency operations centres, should the need arise.

Rapid responder personnel are being increased to the same level as 2011.

The Provincial Disaster Assistance Program Response Teams are preparing to set up locations in severely impacted communities to assist claimants and local officials.

PDAP is currently in the midst of hiring additional staff to ensure needs are met across the province.

Manitoba is also getting prepared.

The Manitoba Infrastructure and Transportation Hydrologic Forecast Centre's second 2013 flood outlook calls for increased spring flooding potential on the Red, Souris, Pembina, Assiniboine, Saskatchewan and Qu'Appelle rivers, and in the Interlake, due to additional March snowfall, above‑average snowpack with high water content in many parts of the province, and low temperatures that are keeping frost in the ground longer than normal.

Manitoba provincial forecasters say, while these conditions have increased the risk of flooding to moderate to major, up from minor to moderate as forecast earlier this year, the current outlook does not foresee prolonged river flooding and high lake levels as in 2011. The outlook has trended towards the 2009 flood in the Red River Valley and the Interlake.

In addition to heavier-than-average snowfall, which was 200 per cent of normal in much of Manitoba, Saskatchewan and North Dakota this month, provincial forecasters have concluded that cooler‑than‑normal temperatures have increased the depth to which soil remains frozen. Across southern Manitoba, soil is frozen to a depth of between 50 centimetres (1.5 feet) to more than 100 cm (three ft.), mainly due to prolonged periods of very cold temperatures. Frozen soil does not absorb meltwater as easily as thawed soils, and it can increase spring run-off and overland flooding.

The colder-than-normal temperatures will also cause a later spring melt, which increases the likelihood of a rapid melt. Cool temperatures later into the year also increase the likelihood that the melting snowpack and normal spring rains will occur at the same time.

While all these factors have increased the risk of flooding to moderate to major, conditions can change quickly and the outlook is still very dependent on weather conditions from now until the spring melt.

The Assiniboine River is high for this time of year due to controlled releases from the Shellmouth reservoir, which have brought the reservoir down to near-record low levels to accommodate potential high water flow from Saskatchewan's above-average snowpack.

This year, 90 volunteers throughout Manitoba provided snow information, such as depth and density, on a regular basis to the forecasting centre, which has proved to be an invaluable data source in the development of this year's forecasting.

The province also installed 22 new hydrometric stations for a total of 315 stations on Manitoba's rivers and tributaries. These stations transmit real-time water levels and flows by satellite to Manitoba Infrastructure and Transportation's Hydrologic Forecast Centre.

In addition, the province has purchased two portable acoustic velocity meters, which can be moved around the province to take real-time water data readings.

Provincial crews have inspected and made repairs at critical locations along the 160 km of Assiniboine River dikes which were heavily damaged in the 2011 flood.

Manitoba's Amphibex fleet can be deployed quickly to trouble spots throughout the province to break up ice jams as needed. The province is also stationing land-based heavy equipment at strategic locations and bridges along the Icelandic and Fisher rivers to combat ice jamming.

The province also has two million sandbags and sand, six sandbagging machines, 17,000 super sandbags, 43 km of Hesco cage barriers, 50 km of water-filled barriers, 61 heavy-duty steamers and 34 mobile pumps ready to deploy on an emergency basis.

The Manitoba government has hosted more than a dozen training sessions with municipal emergency management staff as well as regional pre-flood information sessions with officials in Brandon, Morris and Selkirk. The province will begin regular regional forecast reviews with municipalities as the spring melt begins.

The province will have staff dedicated to work directly with First Nations on the flood forecast. The province will continue to work with Aboriginal Affairs and Northern Development Canada to ensure that First Nation communities are prepared for potential flooding.

There is a risk of moderate to major flooding on the Assiniboine River due to normal to above-normal average soil moisture in the upper portions of the watershed and above-normal snow-water equivalent in most of the basin. An unfavourable weather scenario would result in major flooding of the Assiniboine Valley from Shellmouth to Brandon similar to those levels of 1974 but lower than those of major floods in 2011, 1995 and 1976. Brandon flood protection works are higher than the predicted flows.

Homeowners need to be aware that standard insurance doesn't cover overland flooding.

"It's important to take preventative action against severe weather during the spring thaw as damage caused by overland flooding is not covered by home insurance policies anywhere in Canada," says Bill Adams, Vice-President, Western and Pacific for the Insurance Bureau of Canada. "Sewer backup coverage, however, is usually available and can be purchased as an add-on to policies."

A few suggestions from the Insurance Bureau to prevent flooding:
- Clear snow about three to five feet away from the house foundation to prevent leaks.
- Examine attic for frost accumulation. Check roof for ice dams or icicles. If there is excessive frost or staining of the underside of the roof, or ice dams on the roof surface, consult the tips from Canada Mortgage and Housing Corporation for practical solutions.
- Move valuable items from the basement to upper floors.