Snowpack is increasing in mountains

The seemingly endless weather systems that have moved through over the past two weeks have soaked Weiser and dumped lots of snow in the mountains.

 The snowpack in the Weiser River drainage in many areas has doubled over the past month and in one location now sits at nearly 10 feet of snow.   

 It appears that irrigators and farmers will have plenty of water for the summer growing season in and around Weiser and the west end of the Treasure Valley. 

 But as the snow continues to pile up in the mountains, the concern turns to the potential for flooding in Weiser when it melts.

 The Snotel automated measuring site at Squaw Flat at 6,240 feet in elevation recorded an increase in the snowpack from 49 inches on Jan. 27 to 102 inches of snow as of Monday.  

 Another Snotel site in the Weiser River drainage, Bear Saddle, which is located at 6,180 feet in elevation, increased from 51 inches to 91 inches of snow in the past month. 

 The snowpack at Van Wyck, one of the lower Snotel sites in the Weiser River basin at 4,920 feet, increased from 22 inches of snow on Jan. 27 to 50 inches as of Feb. 25.

 Overall, the Weiser River basin was at 141 percent of average on Monday for snow-water equivalent, a measurement of the water content in the snowpack.

 Even with all the rain and the new snow in the higher elevations, flooding on the Weiser River looks fairly unlikely right now, Washington County Emergency Management Director Tony Buthman said.

 “I don’t foresee us having any issues,” he said.

 While flooding appears to be unlikely, the assessment comes with a disclaimer. If all the elements came together, such as heavy rain and 70 degrees, the situation could change. 

 On the Weiser River, there are no dams to hold any runoff, so there is no way to control the amount of water coming down the river from snowmelt. 

 As of last week there was only a 10 percent to 25 percent chance that the Weiser River could reach 12 feet or above flood stage, Buthman said. 

 The Weiser River flooded in early February of 2017. The flooding forced some evacuations in southeast Weiser and closed Highway 95 south of the main bridge into Weiser. 

 The situation on the Weiser River was much different two years ago, Buthman said.

 In 2017, weeks of subfreezing temperatures had frozen sections of the Weiser River. When the ice began to melt it moved downstream and created an ice jam that was about two miles long extending downstream and upstream from the Highway 95 bridge at Weiser.  

 The ice jam caused the river to back up and flow over its banks above the Cove Road bridge and into low-lying areas upstream from Weiser. 

 There is no ice on the Weiser River right now. High water from runoff will not be impeded as it flows to the Snake River southwest of Weiser, Buthman said. 

 Unlike two years ago, the Snake River is low and would not cause any backup of high flows on the  Weiser River. The levees have been fixed in the river to keep the water in the correct channel.

 The Natural Resources Conservation Service will issue its March water outlook on March 1. It’s expected to show a boost in the snowpack and snow-water content in many areas of the state.

 Officially, winter continues until March 20. Although the big snow months are usually November, December and January, this year storms in February have been the big snow producers in the mountains.