Eastern Idaho water supply outlook is optimistic
BOISE, Idaho (KIFI/KIDK)-Except for the upper Snake River and Bear River drainages, April was an exceptionally dry month in Idaho.
Most of the state received between 50-80% of normal monthly precipitation, according to the Natural Resources Conservation Service (NRCS). In the upper Snake, however, 100-120% normal precipitation was recorded in sub-basins above American Falls.
The NOAA Climate Prediction Center suggests May will be similar.
“Seasonal peak snowpack has passed for nearly all of Idaho’s mountains, as widespread and rapid snowmelt took place during April, said Daniel Tappa, Supervisory Hydrologist with the Idaho Natural Resources Conservation Service. “In addition, streamflow forecasts have largely decreased since April 1 with the exception of northern Idaho (Panhandle & Clearwater) and far eastern Idaho (Upper Snake & Bear River) where remainder season streamflow is forecast to be near normal.”
During April, except for the Henry’s Fork-Falls River Basin, all upper Snake sub-basins received above normal precipitation. Reservoir storage is at 113% of normal in the upper Snake region. The Jackson-Palisades system is at 70% capacity, which represents 125% of normal.
The NRCS said water managers should have plenty of water for user needs as well as excess water for aquifer recharge.
Precipitation in the Bear River Basin ranged from 70-100% of normal for the month. Total water year precipitation is near normal. Bear Lake is 74% full and 147% of average. And, NRCS calls the water outlook “promising” for the variety of water users and recreationists throughout the Bear River Basin.
The Salmon River basin’s April precipitation was 70% of normal, with 1” to 2” less precipitation than a typical April. So far, water year precipitation is 85% of normal. Streamflow in the region is expected to be about 73% of normal runoff. The Salmon River is likely to peak in late-May or early-June. According to NRCS, continued abnormally dry weather could raise concern for drought in the region.
