Wildcard is the Weather
Now that we are experiencing a break in the very snowy weather from February, our thoughts may be turning to time at our lake and how high the lake may reach during the spring freshet. Will we be dealing with high water issues this year? This concern could be exacerbated by recent articles in the press about the potential for flooding in some BC watersheds.
In researching this question, we have reviewed the March 1, 2018 Snow Survey and Water Supply Bulletin prepared by the BC. Provincial River Forecast Centre (https://www2.gov.bc.ca/gov/content/environment/air-land-water/water/drought-flooding-dikes-dams/river-forecast-centre/snow-survey-water-supply-bulletin). While it is still early to come up with a definitive answer to whether we could expect flooding issues on the Shuswap, the forecast indices indicate that snowpack in the South Thompson watershed are above normal (111% of Normal). This is identical to conditions for this time of year in 2016.
However, the volume runoff forecast (including runoff from snow melt and rain) for the South Thompson River at Chase (at the outlet of Little Shuswap Lake) for March to July runoff is lower, 104% of normal. Given that the lake is currently about 0.3 m lower than normal, this information suggests that we should not expect above normal lake levels this year.
Of course the wildcard is the weather. A warm, wet spring that brings off the snow pack faster would change this outlook.
We remain cautiously optimistic and will give you an update when the April 1 water supply bulletin is available.