RBC I Following major storms in December, Colorado snowpack looked pretty good, even measuring above average around most of the state. The welcome precipitation broke a “particularly dry” early winter, pushing snowpack to above median levels in some areas of the state. This led experts to project “well above normal” streamflow forecasts for all major river basins.
As a result of continued dry conditions year-over-year, hydrologists have noted that above-average snowpack is now necessary in order to see stream flows closer to “normal,” since increased temperatures and less moisture overall means dryer soil, which means less runoff making its way into the surface water. “Dry soil conditions going into winter can reduce the observed streamflow relative to what the observed peak snowpack ends up being,” said NRCS Hydrologist Karl Wetlaufer.
Though December’s “exceptional precipitation” may have offered a glimpse into a pre-megadrought water year, dry conditions in January brought snowpack and water supply projections back to normal for most of the state. NRCS February 1 report notes “A ridge of high pressure in January left much of Colorado drier than normal for the month.” The Colorado Headwaters and combined Yampa-White-Little Snake river basins received 76 and 72% of normal precipitation, respectively. Some of the effects of these facts are:
• snowpack dropped from 126% to 105% of median
• water year-to-date precipitation dropped from 120% to 106% of median
• streamflow forecasts dropped from 115% to 93% of median
The report also highlighted reservoir storage as a “major consideration” since most reservoirs in the state are below-normal and hold less acre-feet of water than they did a year ago. Wetlaufer added “it should also be kept in mind that Lake Powell and Lake Mead are also at the lowest levels on record which has an effect on the entire Colorado Basin and can continue to affect the headwaters here in Colorado.”
White River Conservancy District director Alden Vanden Brink also commented on storage concerns during this week’s board of commissioners meeting. He stated “Unless we start getting some storms, we’re looking at a similar situation if not slightly worse than last year in water storage.”
As of Feb. 1, total snow accumulation for the year was around 60% of normal, so putting the “dry January” aside, current projections for snowpack and runoff are still normal/near normal for most of the state, assuming we see at least a normal amount of precipitation for the remainder of the winter.
By LUCAS TURNER | [email protected]om
