Idaho's water supply holding steady

| March 5, 2016 8:00 PM

The snowpack in most of Idaho’s mountain ranges is near normal or better than normal for this time of year.

The Natural Resources Conservation Service’s new water supply outlook for the year shows the snowpack ranges from 90 to 110 percent for most of the state.

The lowest snowpacks are in isolated pockets at 85 percent of normal in the Spokane and Little Wood basins.

Researchers say snowpack density is the name of the game right now, as the higher the density the “riper” the snow is for melting. Snow typically melts when its density reaches 40 to 45 percent.

“Normally the densities of Idaho’s various snowpacks are in the 30 to 34 percent range for this time of year,” said Ron Abramovich, water supply specialist with the Natural Resources Conservation Service. “However, many sites are reporting higher densities — in the 36 to 38 percent range. The warmer February temperatures have allowed the snow to begin ripening up much earlier.”

Based on Idaho’s March’s Surface Water Supply Index (SWSI), irrigation supplies should be adequate across most of the state, but are still marginal at best in the Big Wood, Big Lost and Little Lost basins. Additional winter storms or good spring precipitation is needed to ensure adequate irrigation supplies.

With a near-normal or better snowpack across the state, things are looking promising for all who depend on Idaho’s snowfall and resulting runoff for their entertainment or livelihood. More snow in the mountains this year means the ski season isn’t over yet and the spring-summer recreation season will be excellent for the river runners and power boaters.

“Despite receiving below-normal February precipitation, we remain near normal overall,” Abramovich said. “There does appear to be some good news on the horizon, as weather patterns appear to be changing during the first full week of March and have the potential to bring abundant moisture to Idaho. Hopefully the temperatures will be cold enough to allow the precipitation to fall as snow in the higher elevations.”