By Irene Shonle, Director CSU Extension in Gilpin County
Overall, snowpack in Colorado is great so far this year (statewide, 114% of normal).
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| Snotel Current Snow Water Table |
As of February
25th, the South Platte River Basin (our watershed) is 110% of normal
and the Arkansas is 125%. West slope river basins range from 107% to 122%. This is great news to urban dwellers, to
farmers and ranchers and to states downstream from us to whom we owe water, since
that snowpack will soon be melting into water and rushing down the mountains
in our streams and rivers. This is
especially welcome news after the dismal snowpacks of the last few years.
However, river basin snowpack means very little to us
locally. The water many of us mountain dwellers drink comes from wells, and not
from reservoirs or large underground aquifers as it does in the flatlands. The production of those wells is entirely dependent on the precipitation that
falls in our own yards. It’s very local. And, along the Front Range, from about
7,500’ to 9,000’, we have not gotten great snowfall amounts this year. We are not on
the Snotel site, so it doesn’t really show up anywhere, but most of our
snowfalls this winter have just been a few inches or so. As one long-time
Gilpinite said, you know snowfall has been scarce when 8” seems like a big
snow! I have heard reports of wells going dry already this winter. It’s been
that way for the last couple of years, and I am hoping for some bigger snows
this spring. We need it!
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| Aquifer diagram |
Our wells gather water from melting snow and rain
seeping into tiny cracks in the bedrock. The ground water held in these cracks
is called a fractured rock aquifer and is only recharged by precipitation. Some
of these cracks are as narrow as a human hair, and they are all connected to
each other for water to be able to travel through them to your well. This
ground water recharge system also explains the phenomenon of well water
discoloration in the spring – when large quantities of water enter the
fractured rock aquifer when the snow melts, sediments, nutrients and tannins
can be carried along. Shallower wells
tend to see this more frequently -- even after a big rain -- whereas deeper
wells see it only in the spring or not at all.
Local moisture also has a big impact on the moisture
content of trees and fire danger, and yes, the performance of your perennial
plants in your garden. The last few years, at least in Gilpin County, have not
seen good summer rains either, so this year it would be good to have some spring snows followed by summer rains. There is a somewhat increased
probability for above average precipitation this spring, so here’s to hoping!
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| Three-month precipitation outlook |
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