Summer water supplies look promising due to snowpack

No more cloud seeding and dust season may be nigh 

By Alissa Johnson

All it takes is a look at Gunnison Valley snowbanks to tell that this winter brought a lot of snow. But the data confirms it: The current snowpack is strong. It bodes well for summer water supplies, even with a dry long-term forecast.

“The March 1 snowpack numbers are very encouraging. The one cause for some concern is that there’s not much in the way of precipitation in the long-range forecast, so at this point we’re cautiously optimistic that we’re going to have a good runoff season,” said Frank Kugel, general manager for the Upper Gunnison River Water Conservancy District.

He indicated that the snowpack at the SNOTEL (snow telemetry) site on Crested Butte Mountain is reporting the current snowpack at 181 percent of the median snowpack for this date, and Schofield Pass is at 175 percent. The site at Taylor Park is at 197 percent of the long-term median.

While it is difficult to imagine a scenario in which conditions change drastically enough to hurt water supplies, Kugel explained that “water managers plan for the worst and hope for the best.”

As a result, Kugel and other water managers have their eyes on three areas of concern: a prolonged period without precipitation; a prolonged period of abnormally high temperatures; and large dust events.

The concern is that under these scenarios, the snowpack could melt earlier than normal or evaporate before melting and joining local streams or groundwater.

While Sunday evening brought high winds to the valley, along with reports of dust, it appears to be a localized event. The dust season—during which Utah dust settles onto Colorado snow—has been relatively quiet so far. Kugel confirmed that a February 28 visit to the Taylor Park Dam area revealed no dust. And Jeff Derry, executive director for the Center for Snow and Avalanche Studies, was out in the San Juan mountains Tuesday morning looking for signs of dust and saw none.

“There have been some localized dust events observed in some places around Colorado,” Derry confirmed. “Next week on the 12th and 13th, we’ll be doing a statewide CODOS [Colorado Dust On Snow program] tour where we look for dust at 10 or 11 different sites around the state of Colorado and see where we’re at.”

While it remains to be seen how the long-term forecast comes to pass, one effect of the current snowpack is that cloud seeding efforts in the Upper Gunnison Basin have been suspended. The cloud seeding process releases particles of silver iodide into the atmosphere to encourage the production of ice crystals that grow into snowflakes.

“We have a threshold for operating the cloud seeding program… If areas are above a certain percent as of a certain date then we suspend cloud seeding,” Kugel explained. “We have suspended that because the March 1 threshold is 150 percent. The concern is that if we run those generators, we add to flood risks.”

As of Tuesday, Kugel seemed pretty optimistic about the summer outlook.

“Just looking at the five benchmark SNOTELS we use for determining water supply in the upper Gunnison, today’s date shows we’re at 170 percent of normal and at 135 percent of the normal seasonal maximum. So that number is very encouraging and it would be hard to anticipate that we would have a below-normal runoff period based on current snowpack,” Kugel said.