Okanagan’s elevated snowpack poses moderate flood risk: River Forecast Centre

An above average snowpack in the Okanagan is putting the region at a moderate flood risk during this spring’s melt, with some localized areas where the threat of flooding related to the snowpack is considered high, according to the province’s River Forecast Centre.

Typically, at this time of year the snowpack is at or near its peak, and the latest measurements for the Okanagan have the snowpack at 116 per cent of normal.

However, David Campbell, who heads up the River Forecast Centre, stresses that the snowpack is only part of the flood risk story.

Weather is the major unknown variable that could determine if the region actually runs into trouble with high water.

Campbell said rain can actually account for up to 40 per cent of the water flowing into local water systems, but according to Environment Canada, long-range precipitation is also notoriously hard to predict.

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The river forecaster is hoping the region will avoid both heavy rains and ongoing cold temperatures that could delay the melt and lead to a sudden surge of melting snow when temperatures do warm up.

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Campbell said it’s the northeast areas of the Okanagan where there’s a greater risk of flooding due to particularly high snowpack.

That includes Mission Creek, which flows into Kelowna, and as Campbell pointed out there is a large snowpack at the headwaters of that river.

In anticipation of higher than normal inflows, Okanagan Lake has been drawn down more than a meter below what’s considered full pool.

Officials are continuing to monitor the lake levels and adjust outflows accordingly.

Meanwhile, Kalamalka Lake has been flagged by the province as an area of potential concern.

Shaun Reimer with the Ministry of Forests, Lands, Natural Resource Operations and Rural Development said the lake is currently 9 cm above where it was in 2018 even though the dam has been wide open since January.

“This could drive some higher flows through Vernon Creek and through the City of Vernon. It is still a little bit too early to tell,” said Reimer noting that it is something that should be monitored.

Reimer said authorities do not have the same ability to draw down Kalamalka Lake, as Okanagan Lake, as there is not enough pressure to push the water out of the Kalamalka Lake until there are higher lake levels.