Much of Idaho has a lower-than-normal snowpack because of sparse precipitation so far this winter combined with above-average temperatures in the last month.
But state and federal weather and water experts at a meeting March 13 of the Idaho Water Supply Committee said water stored from a good water year last year should help carry most irrigators through the growing season.
“As far as the reservoirs are concerned, I think they’re looking fairly well,” said Dan Stanaway, a staff hydrologist with the Idaho Department of Water Resources. “There’s a lot of carry-over from last year. There’s still a lot of water in the system. If we were solely depending on what we had in 2015, it would be a stark picture.”
Ron Abramovich of the National Resources Conservation Service said precipitation has flat-lined since mid-February, and record high nighttime temperatures are leading to a faster melt of the state’s snowpack.
He said that’s a problem because reservoir managers try to avoid filling reservoirs until after mid-May in case there’s a rain-on-snow event that can cause rapid snowmelt and flooding if reservoirs don’t have space for the water.
“They can’t capture it and hold it until later,” Abramovich said. “If the warm weather stays, the farmers are going to start calling for water. If they call for too much in March and April, there’s going to be less for them in July, August and September. It’s a balancing act.”
Mel Kunkel of Idaho Power said the company’s attempts at cloud seeding have been on hold since early February when warm and dry weather moved in.
“Cloud seeding only helps to increase (precipitation) when there are clouds to work with,” he said. “If you have warm clear skies, there’s not much you can do.”
He said the company’s cloud seeding efforts in the Payette and Boise basins have increased precipitation from 5 to 20 percent in previous years.
The hardest hit area is in the Owyhee Basin in southwest Idaho where the snowpack is 30 percent of normal. That’s on top of three previous years where irrigators saw reduced flows because of lack of rain and snow.
“There will be fallowed lands and people doing different crops that are either less water intensive or come off earlier,” said Clancy Flynn, manager of the South Board of Control that covers two irrigation districts.
On a broader scale, Abramovich said, scientists are studying a band of warm water stretching from Mexico to Alaska that is blamed for altering the jet stream and causing it to be dry and warm in Idaho but cold and wet in the Midwest and East.