The breakup of ice on the Clearwater and Athabasca rivers is expected to happen a little earlier this spring than last year, but the risk of flooding is predicted to be average, municipal officials said Wednesday.When the river breakup begins, walking along the river’s edge becomes dangerous. Water levels rise and strong currents shove sheets of ice up onto the banks unpredictably. There is also the risk of ice-jam flooding, as chunks of ice can pile up, stopping the flow of water upstream and causing it to spill over the banks.
“Right now they’re predicting it’s an average season with an average risk of flooding,” said Chris Graham, assistant deputy chief of emergency management with the RMWB.
The predictions are made based on observations from provincial monitoring stations located at key intervals on the rivers and from ice thickness data collected by the municipal engineering department.
In the past three to four years, the area around the municipality has typically seen “dynamic” breakups of shifting river ice for a short time before the ice settles and starts to melt in place, Graham said.
The municipality will not officially declare “river breakup” until the ice is gone from the river and there is no threat of flooding from ice jams further downriver.
The average date for declaring river breakup is April 19, which is when last year’s river breakup was declared. This year it is likely to happen a few days earlier than that, Graham said.
“It’s very visual, and that’s why it attracts so many people,” Graham said.
The river banks are very dangerous at this time of year, however, and should be avoided,…
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