The Government of Yukon has released the March 1 Yukon Snow Survey Bulletin and Water Supply Forecast. The snow survey found that the snowpack in most of the southern half of the territory is close to or slightly above average, and above average in the northern half of the Yukon.
While the snowpack is above average in some parts of the territory, in contrast to the previous two years, the snowpack is much closer to normal. Overall this is the lowest record snowpack for March since 2019.
The Upper Yukon, Teslin, and Stewart basin-wide snow water equivalents are estimated to be close to average. The Alsek basin is estimated to be below average. The Stewart, Peel, Porcupine, Central and Lower Yukon basins are all above average with the most concentrated area of high snowpack centring around the lower White River basin and adjacent areas of the Lower Yukon basins.
Record and near-record high baseflows in many systems indicate well above-average groundwater levels in many areas of the territory. This, combined with above-average snowpack, will lead to higher than average freshet volumes in Yukon lakes and rivers this spring. Higher groundwater levels combined with above-average snowpack also increases the risk of slope failures and localized runoff flooding in low lying areas.
The March 1 snow survey indicates that there will be average to slightly above average flood potential for spring breakup and spring freshet in most of the territory. Above average flood potential areas are likely to include the White River and Lower Yukon Basins.
Snowpack is one risk factor for high water flows, water levels and flooding during the spring breakup and snowmelt period. Spring weather, the timing and progression of snowmelt as well as precipitation events are also important drivers of flooding regardless of snowpack levels.
Every March, April and May, the Government of Yukon conducts Yukon-wide snow surveys to help forecast water levels and flow conditions across the Yukon.
The March 1 snowpack observations provide insight into the development of the snowpack, with the April 1 snow survey typically representing peak snowpack.
The Snow Survey Bulletin and Water Supply Forecasts provide a summary of winter meteorological and hydrological conditions for major Yukon watersheds.
The bulletin provides long-term snowpack averages, monthly data, and current snow depth and snow water equivalent observations for 52 locations in the Yukon, and five locations in the neighbouring areas of British Columbia and Alaska.
Snow water equivalent is the amount of water released from the snowpack when it melts.
Freshet, or spring freshet, is when rivers and lakes rise and peak in response to spring snowmelt. The freshet can last several weeks.
Communications Analyst, Environment