Colorado has reached its peak this week. From here on out, it’s all downhill.
If averages count for anything, that is, the snowpack statewide annually maxes out around the second week in April. Sure, the stuff still falls from the sky, but increasingly warmer days and shorter nights generally keep it from stacking up as fast as it melts off. By most measures, runoff is underway.
As is so often the case, there’s good news and bad when it comes to runoff forecasts for river basins statewide. Fortunately, there’s much more of the former for river enthusiasts this spring. Like Nostradamus, the runoff offers promise.
According to the April 1 survey from the USDA Natural Resources Conservation Service (NRCS), the statewide snowpack total was 113 percent of average and nearly 30 percent higher than a year ago. Multiple mountain storms since that date have bolstered the figures, which should translate to healthy river flows.
But there’s no telling how the water will come down the mountain. A warm, dry spell typically means short, rapid runoff, while lingering cold and precipitation could extend the melt into summer. Already several Western Slope waterways have started showing signs of life, and increasing turbidity as a result.
One thing for sure, though, is this winter’s fabled La Niña weather pattern stayed true to its nature. Most of the storms crossing the state favored the north, while only dusting the southern mountains, according to Allen Green, state conservationist with the NRCS.
River basins in the northern mountains, including the Colorado, Yampa, White and South Platte rivers, are looking at the deepest snowpack since 1996. Currently at 138 percent of average, the North Platte River Basin had the highest basinwide total in the state and the highest for April 1 since basinwide totals began to be calculated in 1968.
Things are going to look drastically different in the north from how they did during last summer’s low runoff.
Meanwhile, the April 1 readings showed snowpack conditions across the southern mountains decline for three consecutive months, placing the Rio Grande and combined San Juan, Animas, Dolores and San Miguel basins well below average. A late boost of snowfall last week bumped the graph up to 79 percent of average in the Rio Grande basin two days after its April 10 average peak, while snowpack in the combined San Juan, Animas, Dolores and San Miguel basins climbed to 88 percent of average. Some smaller tributary basins in the Rio Grande basin have dropped to nearly 50 percent of average.
As one might expect, the NRCS offers a grim outlook for spring and summer water supplies across southern Colorado. Expect below average runoff throughout the Rio Grande, San Juan, Animas, Dolores, San Miguel and the southern tributaries of the Arkansas basin this year. The best advice for both fishermen and boaters — get there early.
Statistically speaking
How snowpacks in river basins around the state stack up:
Upper Rio Grande: Snowpack 79 percent of average, 77 percent of 2010 April 10 average peak date (current peak date, April 12).
San Miguel, Dolores, Animas and San Juan: 88 percent of average, 97 percent of 2010, April 7 average peak date (current peak date, March 29).
Arkansas: 101 percent of average, 101 percent of 2010, April 13 average peak date.
Gunnison: 115 percent of average, 120 percent of 2010, April 12 average peak date (current peak date, April 12).
South Platte: 117 percent of average, 143 percent of 2010, April 23 average peak date.
Upper Colorado: 126 percent of average, 158 percent of 2010, April 14 average peak date.
Yampa and White: 133 percent of average, 155 percent of 2010, April 13 average peak date.
Laramie and North Platte: 138 percent of average, 168 percent of 2010, April 26 average peak date.
