Idaho Water Supply Committee declares “excellent” winter

Idaho’s Water Supply Committee convened in Boise Friday to review mountain snowpack, irrigation supply, and projected streamflow runoff. And, snowpack, weather and hydrology experts agree the situation is excellent in each case.

Henry’s Fork snowpack is currently measured at 114 percent of normal.

The Snake River above Palisades is now 120 percent of normal snowpack and Palisades Reservoir is currently 93 percent full. The reservoir is releasing about 6,800 cubic feet per second. Its hydroelectric plant is operating at full capacity.

American Falls Reservoir is 88 percent full and will fill as flow from Palisades Reservoir moves downstream.

The committee said there is a “high chance” that Palisades Reservoir will fill and irrigators will have a full water supply this year.

Some parts of the state received 55 to 70 percent of normal precipitation for the month of March during the first 8 days of the month.

Soil moisture levels are also very high, even at high elevations.

Runoff on the South Fork of the Snake River is projected to runoff at 110 percent of average. At Jackson Lake, inflows are projected to be 116 percent of average and Island Park inflow is projected at 101 percent of average.

It has also been a successful year, so far, for the state’s Eastern Snake Plain Aquifer recharge program. The Water Resources Board surpassed its record of 317,000 acre-feet of recharge earlier this week. It expects to recharge 370,000 acre-feet of recharge over the full course of the winter.

Idaho Power Company has been cloud seeding all winter long and targeted 35 storms so far. An appraisal of the success of that program will come after the winter season.