Staff at the River Forecast Centre are watching computer simulations and the thermometer, trying to determine if the Fraser River will flood this year.
The Fraser basin overall has a snowpack that is 115 per cent of normal, according to David Campbell, of the B.C. River Forecast Centre. Those are snow conditions experienced one year in 10.
The snowpacks in the upper Fraser and Thompson watersheds are the most significant contributors to water flows in the Fraser Valley, and there the snowpack is not as high, about 105 to 110 per cent of normal.
The Mission/Harrison area has much more snow than normal, over 150 per cent. However, this area is the source of relatively little freshet overall, accounting for only five to eight per cent of the Fraser river flow.
“We’re modelling, and keeping an eye on weather conditions,” he said.
The Fraser basin is a large geographic area. For flooding to occur, there would have to be an extended period of hot weather affecting most of the province – for five days or more, followed by a period of intense rainfall.
In 2007, there was a major flood threat in the region. Dikes protecting Abbotsford and Mission were raised, and 160 soldiers with the 39 Canadian Brigade Group were stationed in Aldergrove, ready to assist.
At that time, the Fraser basin snowpack was 138 per cent of normal. Weather conditions that would cause major flooding did not materialize.