Warming temperatures and 5-10mm of rainfall over the next few days will have an impact on snowmelt. Currently ice covered and frozen ground will allow for 20-40mm of snowmelt runoff to enter creeks and rivers. This accounts for 50% of snow water in the southern portions of the watershed.
Water Resources Manager, Christine McClure says, “Runoff on ice and frozen ground will create a quick rise in water levels on creeks and rivers; However, river flows are below average for this time of year and are not forecasted to over top their banks at this time.”
Small creeks in the southern portion of the watershed will over top their banks and localized flooding in urban areas and ditches will occur. Residents are reminded to make sure their sump pumps are in good working condition, and to help reduce ponding by keeping ditches, culverts, and storm drains clear from obstructions.
Increased flows have the potential for ice breakup. Ice conditions can change rapidly, making ice jamming hard to predict.
McClure adds, “Staff measure snow depth and snow water equivalent twice each month. Staff also use a snow model in order to predict snow melt and changing conditions. Snow in the southern regions of the watershed contains 15-85mm of water. Snow in the northern regions of the watershed contains 60-150mm of water, which is normal to three times the normal amount.”
The temperatures are expected to cool over the weekend, which will slow snow melt and reduce runoff, allowing some relief to the river systems in the days that follow.
Staff will continue to monitor conditions. For current water levels or to report changes in water levels and any observations of ice jamming, residents are encouraged to visit
A Flood Outlook Statement gives early notice of the potential for flooding based on weather forecasts calling for heavy rain, snow melt, high wind or other conditions that could lead to high runoff, cause ice jams, lakeshore flooding or erosion.
This message will be in effect until (or updated before) March 19, 2019