#Snowpack/#runoff news: SW basins are hanging on

Westwide SNOTEL basin-filled map via the NRCS,

From The Pagosa Springs Sun (Randi Pierce):

As of April 1, the snowpack in the San Miguel, Dolores, Animas and San Juan River Basin continued to look strong, sitting at 128 percent of median.

Statewide, the snowpack sat at 111 percent on that date.

“We’re still really high up there compared to some of the statewide drainages,” said Joe Crabb, one of the area’s water commissioners for the Colorado Department of Natural Resources Division of Wa- ter Resources. Crabb presented the informa- tion to the San Juan Water Con- servancy District board during the board’s regular meeting Monday.

While the local basin’s 128 per- cent of median is lower than the March 1 mark of 153 percent of median, it is better than it was in previous years.

The April 1, 2016, snowpack rang in at 84 percent, while the 2014 figure for the same time pe- riod was 86 percent, and, for 2011, was 99 percent. Crabb also explained to the board that recent high winds had the potential to impact the snow- pack by depositing sediment on top of the snow, which increases the rate it melts.

Crabb further noted that the snow water equivalent (SWI, the amount of moisture in the snow) remains good, with Crabb’s pre- sentation showing the SWI at 120 percent of median to date and 117 percent of the seasonal median.

In terms of the river flow, Crabb explained that the San Juan River through Pagosa Springs and the Piedra River had each surpassed 1,100 cubic feet per second (cfs) in March, though the runoff had fallen back in to the range of 600- 630 cfs following that. As of April 12, the flow of the San Juan River had inched back up, ringing in at 716 3 midday, with higher amounts at night. He noted that the peak river flow typically occurs around the end of May or first week of June, with the San Juan and Piedra rivers peaking at about the same time.

From The Leadville Herald:

On April 1 statewide snowpack was at 108 percent of normal, down from 139 percent of normal last month and 156 percent on Feb. 1.

“It has been a bit of a rollercoaster snowpack season,” said Brian Domonkos, Colorado Snow Survey supervisor, referring to record low snowpack accumulation in October and November, followed by record high snowpack accumulation in December and January, and now a return to near record low snowpack accumulation again in March.

Relatively good snowpack remains in the Gunnison, Arkansas, and combined San Miguel, Dolores, Animas and San Juan basins, all above 118 percent of normal. Only the combined Yampa and White basins are now below normal.

March precipitation statewide was 64 percent of average with two SNOTEL sites recording as low as 20 percent of March normals. These low monthly totals dragged down the year-to-date precipitation from 123 percent of average last month to 112 percent on April 1. Fortunately, some recovery came at the month’s end to much of Colorado’s mountains mostly in the form of snow. The South Platte, Arkansas and the Rio Grande basins did receive enough snow to reach new snowpack peaks beyond the peak reached in early March. Snowpack typically peaks for all basins near April 10, the exception being the South Platte, which peaks two weeks later.

At the end of the month the Sangre de Cristo mountains were able to scrounge up considerably more precipitation than the rest of the state, helping to boost the late season snowpack in that region.

“March and April are the two months in which Colorado typically sees the greatest precipitation, accounting for over one-fifth of the year’s total,” said Domonkos. A slow start in March can be overcome in April.

While current snowpack and reservoir storage levels are normal to slightly above normal across much of the state, the recent snowmelt and dry conditions in March had significant impacts. As a result, spring and summer streamflow forecasts have dropped considerably since a month ago.

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