Drought concerns in the winter in Vancouver is one hell of a thought
this post was submitted on 12 Feb 2024
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The concern is not inadequate volume of precipitation.
The problem is: not enough of the precipitation is snow. We rely on alpine snow melt feeding creeks and rivers gradually through the dry months.
Edit to add: We may have to develop water treatment options that can make brackish river water more usable.
I keep hearing about concerns about reservoir levels as well though.
If it was just the difference of melt water to prevent fire conditions, we wouldn't also be hearing about reservoir levels as the rain would end up there either way?
The thing is, reservoirs only hold so much. Get all that moisture at once, they have to release the extra water and it effectively goes to waste. Snow pack melting slowly will add that moisture slowly over the course of a longer time. Snow pack is like a reservoir for the reservoir.
Compound that with hotter summers that have longer periods of little to no precipitation.
The reservoirs are all low right now. If they weren't low right now it wouldn't be as big a problem, but because they are low now, and snowpack is low, its going to be more rough this summer.
My post was responding to someone saying they still had a lot of precipitation, and I thought they'd fill the reservoirs then.
Someone else theorized that the snow melt travels further than the rain due to the frozen ground or ice under the snow and that's why the reservoirs are low even though we are getting a lot of rain.
Around here (southern Saskatchewan), it doesn't take much snow to generate a lot of runoff compared to major dumps of rain. Probably because the snow melt is running over frozen ground. I know spring is here when all of a sudden the big puddle in back of our place just disappears overnight.
So the runoff makes it further along than the rain would is what you're saying?
I'm far from being any kind of expert, but yes, that's the way it looks to me.
The pavement and hard packed gravel roads run pretty close to the same, whether it's meltwater or rain, but the dirt roads, ditches, hills and coulees run very differently. My guess is that with meltwater, the ground is still frozen, so can't absorb the water.