Snowpack, water supply depend on March rains

By Hannah Ashton; Magic Valley Times News


Snow falls as the water flows Wednesday, March 9, 2022, at Auger Falls in Twin Falls.
Drew Nash, Times News

TWIN FALLS — Idaho broke water records in March — not the good kind. Across the state SNOTEL — Snowpack Telemetry sites — hit record low precipitation levels for January to March. Many of the data sets go back 40 years, making officials with the Idaho Water Supply Committee even more nervous. “Since about Jan. 7, we’ve really had a failure of normal precipitation in the state,” said David Hoekema, hydrologist with the Idaho Department of Water Resources, during the March committee meeting. The snow water equivalent (SWE), which stands for how much water is in the snowpack if it melted, has “dramatically decreased,” he said.

Hoekema described the fall and early winter as “perfect conditions” leading the entire state to have above 100% SWE coming into January. A dry spell in February undid that progress, with most of the basins in the state now sitting in the 70-80% range for SWE. Idaho doesn’t need a “miracle March,” however, anything less than normal precipitation would put a strain on irrigation water supplies, according to the Natural Resources Conservation Service.

“March is shaping up to be a ‘make or break’ month for our 2022 seasonal snowpack and eventual water supply,” the service wrote in the March water supply outlook report. South-central Idaho was one of the areas that received “abysmal” precipitation in February, according to the report. All basins south of the Salmon-Clearwater divide received 50% or less than normal amounts of precipitation.

“The infrequent storms that did arrive via northwest flow mostly lacked meaningful moisture due to the ridge of high pressure in the eastern Pacific, which effectively blocked access to tropical moisture,” the report said. Magic Valley residents will still have chances to see rain in March. Weather forecasts are predicting above-normal precipitation, according to the National Oceanic and Atmospheric Administration Climate Prediction Center. Unfortunately, the systems are more likely to hit northern Idaho and west-central mountains harder than southern Idaho, according to Link Crawford, National Weather Service Hydrologist in Pocatello.

To view original article, please click here.