Metro Vancouver crews helicopter into the remote watershed to evaluate the volume of stored water in the snowpack. Early May was looking good, but after several hotter than typical weeks, summer water supply dropped dramatically.
Several times a year, Metro Vancouver staff conduct snow surveys to determine stored snow levels in the Seymour and Coquitlam watersheds. These remote, mountainous sites can only be accessed by helicopter. The combined area of the protected Capilano, Seymour and Coquitlam watersheds is more than 58,000 hectares; about 150 times the size of Stanley Park.
Metro Vancouver manages these three watersheds, each with a water collecting reservoir, to provide 2.5 million residents with a clean, reliable and affordable supply of drinking water.
From the vantage point of the helicopter, the crew express concern seeing the effects of a warm Spring on the terrain. “The month of May was very warm and led to quite a bit of snow loss,” said Metro Vancouver’s Water Protection Officer, Mike Neale. “We’ve lost about a metre of snow much quicker than what we did last year.” Neale explains how having a healthy snowpack provides benefits beyond a reliable supply of drinking water for our reservoirs. “If we are snow-free at higher elevations earlier [in they year] it’s an increased risk of forest fire at all elevation bands,” he said. “Which then can give us multiple incident type situations which we may not encounter on other years.”
The first stop is Disappointment Lake, located in the far reaches of the Coquitlam Watershed. Crews take core samples by shoving a tube-like measuring device vertically into the snowpack to extract a core sample of the snow. The snow water equivalent is considered as the depth of water that would result from melted snow. These measurements combined with those from snow weigh scales allow Metro Vancouver to predict theoretical snowpack water values.
Mike Neale explains the snow survey kit they’re using today remains basically unchanged since 1918, but they also employ modern means. “The technology that we have with our snow depth sensors at the stations has really helped us,” he said. “If we couldn’t fly in here today we’re able to take the instrumentation now and check that with our historical data.”
Neale compares the current snow levels to historical ones, looking for trends that may affect our region’s water supply. “Historical is 1050 and we are at 1017. Depth average is 178 and historical is 181,” he notes. Despite a hotter than normal May, Neale determines this day’s snowpack measurements is within historical levels for this time of year, which bodes well for summer reservoir storage, and good news for Metro Vancouver residents.
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